01-110hce-2-3 power plants and related systems.pdf

NAVAIR 01-110HCE-2-3

1 JUNE 1993 CHANGE 7 – 1 SEPTEMBER 2011

TECHNICAL MANUAL

MAINTENANCE INSTRUCTIONS

ORGANIZATIONAL

POWER PLANTS AND RELATED SYSTEMS

UTILITY HELICOPTER HH-1N/UH-1N

This change includes IRAC 26.

DISTRIBUTION STATEMENT C. Distribution authorized to U.S. Government agencies only and their contractors to protect publications required for official use or for administrative or operational purposes only, determined on 1 April 2006. Other requests for this document shall be referred to Commander, Naval Air Systems Command (PMA-276), RADM William A Moffett Bldg, 47123 Buse Rd, Bldg 2272, Patuxent River, MD 20670-1547.

DESTRUCTION NOTICE - For unclassified, limited documents, destroy by any method that will prevent disclosure of contents or reconstruction of the document.

Published by Direction of the Commander, Naval Air Systems Command

0801LP1118433


A Change 7

LIST OF EFFECTIVE PAGES Insert latest changed pages; dispose of superseded pages in accordance with applicable regulations. NOTE: On a changed page, the portion of the text affected by the latest change in indicated by a vertical line, or other change symbol, in the outer margin of the page. Changes to illustrations are indicated by miniature pointing hands. Changes to wiring diagrams are indicated by shaded areas. IRAC’s 1, 2 and 3 never issued.

Dates of issue for original and changed pages are: Original ............ 0.......... 1 Jun 93 RAC .................. 1........17 Nov 93 RAC .................. 2..........4 Aug 94 Change............. 1........30 Aug 94 RAC .................. 3..........1 Dec 95 Change............. 2........30 Nov 99

(Incl. IRACs 4 thru 10)

Change............. 3........ 15 Feb 02 (Incl. IRACs 11 thru 14)

Change............. 4.......... 1 Feb 04 (Incl. IRACs 15 and 16)

Change............. 5...........1 Apr 06 (Incl. IRACs 17 thru 19)

Change .............6 ...........1 Jul 10 (Incl. IRACs 21 and 23 thru 25)

(Cancelled IRACs 20 and 22) Change .............7 ......... 1 Sep 11

(Incl. IRAC 26)

Total number of pages in this manual is 298 consisting of the following: Page *Change No. No. Title.............................................7 A – B...........................................7 C Blank.......................................7 i ...................................................2 ii – iii ...........................................5 iv – v ...........................................6 vi .................................................7 vii ................................................5 viii ...............................................0 ix – x ...........................................5 xi .................................................4 xii – xiii .......................................5 xiv Blank ....................................5 1-1 – 1-2......................................4 1-3 – 1-4......................................0 1-5...............................................2 1-6 – 1-7......................................5 1-8 – 1-9......................................4 1-10.............................................0 1-11.............................................5 1-12 Blank ..................................5 2-1 – 2-3......................................0 2-4...............................................3 2-5...............................................0 2-6...............................................3 2-7...............................................0 2-8 Blank ....................................0 2-9...............................................0 2-10 Blank ..................................0 3-1...............................................0 3-2 Blank ....................................0 4-1 – 4-13....................................0 4-14 – 4-16..................................4 4-17.............................................3 4-18 – 4-29..................................0

Page *Change No. No. 4-30.............................................5 4-30A ..........................................5 4-30B Blank ...............................5 4-31.............................................0 4-32 – 4-33 .................................4 4-34.............................................0 4-35.............................................5 4-36.............................................0 4-37.............................................5 4-38.............................................2 4-39.............................................5 4-40.............................................4 4-41.............................................2 4-42.............................................4 4-43 – 4-44 .................................5 4-45.............................................4 4-46.............................................0 4-47 – 4-48 .................................4 4-49 – 4-50 .................................0 4-51 – 4-53 .................................4 4-54.............................................0 4-55 – 4-57 .................................4 4-58.............................................0 4-59.............................................4 4-60.............................................5 4-61 – 4-62 .................................0 4-63.............................................4 4-64.............................................0 4-65.............................................4 4-66.............................................6 4-67.............................................0 4-68.............................................6 4-69 – 4-70 .................................5 4-70A – 4-70B ............................5 4-71.............................................5

Page *Change No. No. 4-72 ............................................0 4-73 ............................................4 4-74 ............................................5 4-75 – 4-76 .................................0 4-77 – 4-78 .................................4 4-79 ............................................5 4-80 ............................................0 4-81 ............................................4 4-82 ............................................0 4-83 ............................................4 4-84 ............................................5 4-85 – 4-86 .................................4 4-87 ............................................5 4-88 – 4-89 .................................0 4-90 ............................................4 4-91 ............................................5 4-92 ............................................0 4-93 – 4-94 .................................3 4-94A..........................................5 4-94B Blank ...............................5 4-95 ............................................5 4-96 – 4-97 .................................0 4-98 ............................................3 4-99 ............................................0 4-100 ..........................................4 4-101 ..........................................0 4-102 ..........................................6 4-103 – 4-105 .............................0 4-106 ..........................................2 4-107 – 4-114 .............................0 4-115 ..........................................6 4-116 ..........................................4 4-117 ..........................................3 4-118 ..........................................0 4-119 ..........................................6


Change 7 B/(C blank)

LIST OF EFFECTIVE PAGES - (Continued) Page *Change No. No. 4-120 – 4-121..............................4 4-122 – 4-123..............................0 4-124...........................................4 4-125...........................................5 4-126...........................................0 4-127...........................................4 4-128...........................................2 4-129...........................................0 4-130...........................................4 4-131...........................................6 4-132...........................................0 4-133 – 4-134..............................6 4-135...........................................4 4-136...........................................2 4-137 – 4-138..............................7 4-139 – 4-140..............................0 4-141...........................................4 4-142 – 4-147..............................0 4-148...........................................7 4-148A ........................................7 4-148B Blank .............................7 4-149...........................................0 4-150...........................................6 4-151 – 4-154 Deleted................6 4-155...........................................6 4-156 – 4-161 Deleted................6 4-162 – 4-163..............................0

Page *Change No. No. 4-164...........................................5 4-165 – 4-172 .............................0 4-173 – 4-174 .............................6 4-175...........................................4 4-176 – 4-177 .............................6 4-178...........................................0 4-179...........................................4 4-180 – 4-186 .............................0 4-187...........................................4 4-188...........................................6 4-188A ........................................5 4-188B Blank .............................5 4-189...........................................4 4-190 – 4-192 .............................0 4-193...........................................4 4-194...........................................6 4-194A..................................... 2 4-194B Blank .......................... 2 4-195 – 4-197 .............................0 4-198...........................................5 4-199...........................................2 4-200...........................................0 4-200A ........................................2 4-200B Blank .............................2 4-201 – 4-203 .............................2 4-204 – 4-206 .............................4 4-207...........................................2

Page *Change No. No. 4-208 ..........................................4 4-209 ..........................................3 4-210 ..........................................2 4-211 ..........................................3 4-212 ..........................................2 4-212A........................................2 4-212B Blank .............................2 4-213 ..........................................2 4-214 – 4-215 .............................4 4-216 – 4-217 .............................0 4-218 ..........................................5 4-218A – 4-218C ........................5 4-218D Blank .............................5 4-219 – 4-220 .............................0 4-221 ..........................................2 4-222 ..........................................5 4-223 ..........................................3 4-224 – 4-234 .............................5 Index-1 .......................................4 Index-2 .......................................5 Index-3 – Index-7 ......................4 Index-8 .......................................5 Index-9 .......................................4 Index-10 – Index-11 ..................5 Index-12 Blank ..........................5

*Zero in this column indicates an original page.

This page intentionally left blank.


Change 2 i

TABLE OF CONTENTS Section Page I INTRODUCTION..................................... 1-1 1-1. General...................................... 1-1 1-3. Scope and Arrangement of Maintenance Instruction Manual.................................... 1-1 1-4. Associated Aircraft Manuals.................................. 1-2 1-5. Lubrication and Servicing................................ 1-3 1-7. Support Equipment.................. 1-3 1-9. Consumable Materials ................................ 1-3 1-11. Record of Applicable Technical Directives ............. 1-3 1-13. Quality Assurance.................... 1-3 1-15. Glossary of Terms, Symbols and Abbreviations................. 1-3 1-17. Warnings, Cautions and Notes............................... 1-5 II SYSTEM DESCRIPTION........................ 2-1 2-1. Power Plant Package............... 2-1 2-3. Power Section .......................... 2-1 2-5. Power Lever (Ng) Controls ...... 2-1 2-8. Droop Compensator (Nf) Controls .......................... 2-3 2-11. Air Management System ......... 2-3 2-14. Oil Cooler System .................... 2-4 2-16. Engine Mounts ......................... 2-4 2-18. Engine Compartment Fire Extinguisher Installation ...... 2-4 2-21. Fuel Supply System................. 2-6 2-27. Auxiliary Fuel System.............. 2-7

Section Page III SUPPORT EQUIPMENT MAINTENANCE................................... 3-1 3-1. General ...................................... 3-1 IV ORGANIZATIONAL MAINTENANCE.... 4-1 4-1. Troubleshooting Power Plant and Related Systems............ 4-1 4-6. Power Plant Package Component Replacement..... 4-32 4-135. Power Lever (Ng) Controls....... 4-95 4-145. Droop Compensator (Nf) Controls........................... 4-103 4-156. Air Management System ......... 4-113 4-160. Firewalls .................................... 4-117 4-165. Oil Cooler System .................... 4-119 4-176. Engine Mounts.......................... 4-125 4-180. Engine Compartment Fire Extinguisher Installation ...... 4-127 4-183. Starter-Generator ..................... 4-133 4-189. Power Plant Change Procedures ............................ 4-134 4-192. Power Plant Package ............... 4-138 4-197. Engine Water Wash Provisions.............................. 4-155 4-203. Fuel Supply System ................. 4-166 4-239. Auxiliary Fuel System ................................... 4-198 4-243. Preliminary Automatic (AFCU) to Manual Fuel Control (MFCU) Rigging................................... 4-201


ii Change 5

TABLE OF CONTENTS (Continued) Section Page 4-247. Maximum NG and Manual to Automatic Interconnect Linkage Adjustment ............. 4-206 4-249. Acceleration Check and Adjustment..................... 4-209 4-253. Ignition System Check............. 4-212A 4-257. AFCU Minimum Governing Speed Adjustment ............................ 4-218 4-258. Torque Control Unit Maximum Torque Limit Check and Adjustment (AFC 363 Aircraft) ................. 4-218 4-258A. Torque Control Unit Maximum Torque Limit Check and Adjustment (Pre-AFC 363 Aircraft) .......... 4-218B

Section Page 4-258B. Torque Control Unit Equalizing Function Check ..................................... 4-218B 4-259. Power Turbine Governor Matching ................................ 4-219 4-260. Reduction Gearbox (RGB) Oil Pressure Adjustment............ 4-220 4-267. Power Section Oil Pressure Check/Adjustment ................ 4-224 4-268. Compressor Bleed Valve......... 4-227 ALPHABETICAL INDEX...............................Index-1


Change 5 iii

LIST OF ILLUSTRATIONS Number Title Page 2-1. Power Section Lubrication System Schematic....................... 2-2 2-2. Power Plant Package Orientation ................................... 2-3 2-3. Air Management System Schematic..................................... 2-5 2-4. Auxiliary Fuel System Schematic..................................... 2-9 4-1. Oil Filter Element (Typical) and Oil Pressure Transmitter. ........... 4-34 4-2. Centrifugal Breather Face- Type Carbon Seal ........................ 4-36 4-3. Face Seal Removal from Carrier.................................. 4-37 4-4. Output Shaft Face Seal (Pre-PPC No. 8)............................ 4-38 4-5. Removing Output Shaft Seal Nut ........................................ 4-39 4-6. Output Shaft Face Seal (Post PPC No. 8) .......................... 4-41 4-7. Replacement of Accessory Drive Seals (Typical) ................... 4-43 4-8. Accessory Drive Seal – Blower Drive ................................ 4-45 4-9. Oil to Fuel Heater, Fuel Pump and Filter................... 4-46 4-10. Automatic Fuel Control.................. 4-49 4-11. Manual Fuel Control Unit ............... 4-50 4-12. Ignition Exciter Unit and Spark Igniters (Typical)............... 4-55 4-13. Compressor Inlet Screen ............... 4-56 4-14. Flow Divider, Fuel Manifold Adapter and Nozzles ................... 4-58 4-15. Combustion Chamber Drain Valve................................... 4-61 4-16. Power Turbine Governor ............... 4-62 4-17. Torque Control Unit........................ 4-64 4-18. Torque Control Unit Priming Circuit (Pre-PPC No. 70) ............. 4-66 4-19. Torque Control Unit Priming Circuit (Post PPC No. 70)............ 4-67 4-20. P3 Tube from AFCU to Gas Generator Case.................... 4-70A 4-20A. P3 Tube from Front Fireseal to Gas Generator Case (PPC 85)........................................ 4-70B

Number Title Page 4-21. P3 Tube to Reduction Gearbox ........................................ 4-72 4-22. No. 2 Bearing Scavenge, Pressure Transfer and Scavenge Oil Tubes..................... 4-75 4-23. Pressure Oil Tube from Reduction Gearbox...................... 4-76 4-24. Pressure Oil Sense Line to Check and Relief Valve ............... 4-80 4-25. Pneumatic Sense Lines – AFCU to Reduction Gearbox ................. 4-82 4-26. Heated Pneumatic Tube Electrical Connector and Protective Boot..................... 4-85 4-27. Fuel Transfer Tubes ....................... 4-88 4-28. Fuel Surge Dampener..................... 4-90 4-29. ITT Thermocouple Harness (Pre-PPC 76).................. 4-92 4-30. ITT Thermocouple Harness (Post PPC 76 and ECP T400-8).................................. 4-94 4-31. Power Level Controls – Lower Section .............................. 4-96 4-32. Power Lever Controls - Upper Section .............................. 4-97 4-33. Power Lever Control Wear Limits .................................. 4-99 4-34. Power Lever (Ng) Controls ............. 4-101 4-35. Idle Stop Solenoid Installation.................................... 4-102 4-36. Droop Compensator Components................................. 4-194 4-37. Droop Compensator Cambox Assembly....................... 4-105 4-38. Droop Compensator Controls – Wear Limits................ 4-107 4-39. Droop Compensator (Nf) Controls ........................................ 4-108 4-40. Droop Compensator – Bellcrank Shear Section ............. 4-109 4-41. Cowling – Transmission and Air Inlet .................................. 4-110 4-42. Cowling – Power Plant ................... 4-111 4-43. Cowling – Reduction Gearbox ........................................ 4-112


iv Change 6

LIST OF ILLUSTRATIONS (Continued) Number Title Page 4-44. Air Management System Installation.................................... 4-114 4-45. Engine Water Wash Provision ...................................... 4-116 4-46. Firewall Removal and Installation.................................... 4-118 4-47. Oil Coolers and Lines..................... 4-122 4-48. Oil Cooler – Blowers ...................... 4-124 4-49. Blower – Wear Limits ..................... 4-126 4-50. Engine Mounts – Wear Limits ....... 4-128 4-51. Engine Mounts................................ 4-130 4-52. Fire Extinguisher Installation.................................... 4-132 4-53. Use of Lifting Sling and Stand ..................................... 4-135 4-54. Cowl Installation ............................. 4-140 4-55. Reduction Gearbox Vent Hose and Oil Filter....................... 4-142 4-56. Removal of Exhaust Ejectors and Upper Aft Firewall ................................... 4-143 4-57. Removal of Upper Centerline Firewall....................... 4-144 4-58. Removal of Upper Induction Baffle and Middle Firewall with Attached Ducts .................... 4-145 4-59. Engine Connections (LH Side Shown) .......................... 4-146 4-60. Engine Connections (Aft Side Shown).......................... 4-147 4-61. Deleted 4-62. Deleted 4-63. Deleted 4-64. Deleted 4-65. Deleted 4-66. Deleted 4-67. Accessory Locations ..................... 4-162 4-68. Fuel Supply System – Crashworthy Fuel System ................................. 4-168 4-69. Pressure Fueling Provisions .................................... 4-176 4-70. Center Cell Access Door Connections................................. 4-179 4-71. Foam Baffles in Center Aft Fuel Cell.................................. 4-180 4-72. Folding Fuel Cells for Removal or Installation............... 4-182 4-73. Foam Baffles in Left Aft Fuel Cell........................................ 4-185

Number Title Page 4-74. Foam Baffles in Right Aft Fuel Cell.................................. 4-186 4-75. Forward Fuel Cell Sump Assemblies................................... 4-190 4-76. Foam Baffles in Forward Fuel Cells...................................... 4-196 4-77. Auxiliary Fuel Tank Installation.................................... 4-200 4-78. Part Power Trim Stop ..................... 4-202 4-79. Location of Levers on Manual Fuel Control .................... 4-204 4-80. ITT Limiter and Trim Adjustment ................................... 4-210 4-81. ITT Terminal Block and Bracket Connections................... 4-212 4-82. ITT Harness Insulation Resistance Check........................ 4-213 4-83. ITT Harness Loop Resistance Check........................ 4-213 4-84. Power Assurance Check Chart.............................................. 4-216 4-85. Topping Check Chart ..................... 4-217 4-85A. Torque Control Unit Maximum Limiting Check and Adjustment................................... 4-218C 4-86. Torque Control Unit Check ............................................ 4-219 4-87. Air Flow Jet Installation ................. 4-220 4-88. Oil Pressure Regulating Valve Reduction Gearbox ..................... 4-221 4-89. Oil Temperature vs. Oil Pressure ....................................... 4-225 4-90. Power Section Oil Pressure Regulating Valve Adjustment ................................... 4-226 4-91. PPC 86 Bleed Valve and Bubbler Assembly, P/N PWC70513, Adjustment .............. 4-230 4-92. Compressor Bleed Valve Installation/Removal.................... 4-231 4-93. PPC 86 Compressor Bleed Air Valve Closing Point Chart........... 4-232 4-94. Pre-PPC 86 Fabrication of Bleed Air Valve Bracket .............. 4-233 4-95. Pre-PPC 86 Compressor Bleed Air Valve Closing Point Chart .... 4-234


Change 6 v

LIST OF TABLES Number Title Page 1-1. Support Equipment ........................ 1-6 1-2. Consumable Materials ................... 1-8 1-3. Record of Applicable Technical Directives.................... 1-10

Number Title Page 4-1. Troubleshooting.............................. 4-4 4-2. Component Replacement Checks .......................................... 4-33 4-3. Deleted


vi Change 7

TECHNICAL PUBLICATION DEFICIENCY REPORT

INCORPORATION LIST

The following TPDRs are incorporated as part of this change. This page shall remain with this change; next change will provide new listing page with latest TPDR incorporation.

ORIGINATOR REPORT CONTROL NUMBER

None


Change 5 vii

WARNINGS APPLICABLE TO HAZARDOUS MATERIALS

Warnings in this manual alert personnel to hazards associated with the use of hazardous materials. Additional information related to hazardous materials is provided in OPNAVINST 5100.23, Navy Occupational Safety and Health (NAVOSH) program manual, OPNAVINST 4110.2, Navy Hazardous Material Control and Management (HMC&M), and the DOD 6050.5, Hazardous Materials Information System (HMIS) series publications. For each hazardous material used within the Navy, a Material Safety Data sheet (MSDS) must be provided and available for review by users. Consult your local safety and health staff concerning any questions regarding hazardous materials, MSDS, personal protective equipment requirements, and appropriate handling and emergency procedures and disposal guidance.

Under the heading “HAZARDOUS MATERIALS WARNINGS”, complete hazardous material warnings are listed by (1) warnings sequentially assigned index numbers, (2) material, (nomenclature, specification, including related icons), and (3) complete warnings, including appropriate personal protective equipment requirements.

In the text of the manual, the caption “WARNING” will not be used for hazardous materials warnings. Hazards are cited by numeric identifier that relates to the complete warnings, the nomenclature and applicable specification of the hazardous material, and appropriate icon(s). Users of hazardous materials shall refer to the complete warnings.

EXPLANATION OF HAZARDOUS MATERIALS ICONS

Biological The abstract symbol bug shows that a material may contain bacteria or viruses that present a danger to your life or health.

Chemical The symbol of drops of a liquid onto a hand shows that the material will cause burns or irritation to human skin or tissue.

Explosion The rapidly expanding symbol shows that the material may explode if subjected to high temperature, sources of ignition, or high pressure.

Eye The symbol of a person wearing goggles shows that the material will injure the eyes.


viii

EXPLANATION OF HAZARDOUS MATERIALS ICONS (Cont)

Fire The symbol of a flame shows that the material may ignite and cause burns.

Poison The symbol of a skull and crossbones shows that a material is poisonous or is a danger to life.

Radiation The symbol of three circular wedges shows that a material emits radioactive energy and can injure human tissue or organs.

Vapor The symbol of a human figure in a cloud shows that vapors of a material present a danger to life or health through inhalation.

Cryogenic The symbol of a hand in a block of ice shows that the material is extremely cold and can injure human skin or tissue.


Change 5 ix

HAZARDOUS MATERIALS WARNINGS Index Material Warning 1. LUBRICATING OIL

MIL-PRF-23699

MIL-PRF-23699 Synthetic Aircraft Turboshaft Lubrication Oil can irritate skin or eyes upon contact. May contain a neurotoxin that can be absorbed through the intact skin. Symptoms of overexposure include tingling or numbness in hands or feet. Wear nitrile gloves, chemical protective goggles. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

2. TURBINE FUEL, AVIATION

MIL-DTL-5624

MIL-DTL-5624 (JP-5, JP-8) Aviation turbine fuel may cause skin and eye irritation. Inhalation can cause headache, dizziness and nausea. Use chemical splash proof goggles, nitrile rubber gloves, smock or coveralls, and adequate ventilation. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

3. CALIBRATION FLUID

MIL-PRF-7024

Calibration fluid is a skin and eye irritant. Aerosol may irritate the respiratory tract. Use only in an enclosed, ventilated test stand. Do not allow contact with skin or eyes. Use nitrile gloves, goggles and faceshield for protection. Dispose of fluid-soaked cleaning cloths in approved metal safety container. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

4. SEALING, LOCKING,AND RETAINING

MIL-S-22473 (ASTM D5363)

MIL-S-22473 sealant may cause eye and skin irritation. Wear gloves and safety glasses. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.


x Change 5

HAZARDOUS MATERIALS WARNINGS (Cont) Index Material Warning 5. PETROLATUM

VV-P-236

Petrolatum can irritate skin and and eyes. Avoid contact and wash hands after use. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for more information.

6. SEALING COMPOUND, DC4/GREASE

SAE-AMS-G-4343 LUBRICANT, PLASTILUBE NO. 3

SAE AMS-G-4343 Pneumatic system grease may irritate eyes. May irritate skin after prolonged or repeated contact. Wear safety glassed and nitrile gloves. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

7. DRY CLEANING AND DEGREASING SOLVENT

MIL-PRF-680, TYPE II

MIL-PRF-680 Dry Cleaning Solvent may cause eye and skin irritation. Over exposure may cause dizziness and other central nervous system effects. Wear nitrile gloves and chemical protective goggles. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

8. SEALING COMPOUND

AMS-S-8802

AMS-S-8802 Sealants can irritate skin and eyes. Repeated or prolonged contact can cause an allergic skin reaction. Do not sand or grind on cured material. Use gloves, safety glasses and adequate ventilation. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

9. ACETONE, TECHNICAL

ASTM D329

ASTM D329 Acetone is flammable. Do not use near heat, sparks, open flames, or any other source of ignition. Use only in well-ventilated area. Liquid and vapors may irritate the eyes and skin. Prolonged inhalation of vapor can irritate mucous membranes and can cause dizziness and headache. Do not breathe vapors or allow contact with skin or eyes. For protection use butyl rubber gloves, chemical splash goggles. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.


Change 4 xi

HAZARDOUS MATERIALS WARNINGS (Cont) Index Material Warning 10. SILICONE RUBBER ADHESIVE

MIL-A-46106

Adhesive, MIL-A-46106, is toxic and flammable. Avoid contact with eyes and skin. Avoid prolonged breathing of vapor. Keep away from heat, sparks and open flame. PPE: gloves, goggles. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

11. CLEANING COMPOUND

MIL-PRF-87937

Cleaning Compound, MIL-PRF-87937, is irritating to the eyes and skin. Keep compound off skin, eyes and clothes. Do not breathe vapors. PPE: chemical splash proof goggles and face shield, gloves and good ventilation Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

12. LIQUID PENTRANT EXAM

ASTM E1417

ASTM E 1417 Fluorescent Penetrant materials may cause irritation to skin and eyes. Avoid inhaling powder or vapors, and use only in well-ventilated area. Avoid prolonged or repeated contact with skin. Wear nitrile gloves and safety glasses. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

13. ADHESIVE

NO. 4

Adhesive/sealing compounds contain organic solvent and are flammable – do not use near open flames, welding areas oron hot surfaces. Do not smoke when using or when others are smoking. Prolonged breathing of vapors is dangerous. Use in well ventilated spaces. Use respiratorin confined areas. Avoid skin contact. Prolonged or repeated skin contact can have a toxic effect on affected skin area. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for more information.


xii Change 5

HAZARDOUS MATERIALS WARNINGS (Cont) Index Material Warning 14. NITROGEN

A-A-59503, TYPE I

Nitrogen (gaseous) A-A-59503 is a nontoxic, inert gas that may displace the air used for breathing and cause asphyxiation. Use nitrogen in a well ventilated area. Wear safety glasses. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

15. GAS PATH CLEANER

B AND B 3100

Cleaning compound is combustible – do not use near open flames, welding areas, oron hot surfaces. Dispose of liquid-soaked rags in approved metal container. Contains aromatic solvent. Prolonged contact of skin with liquid can cause irritation. Inhalationof vapor can cause headache and light – headedness. If there is any prolonged contact with skin, wash affected area with soap and water. If liquid contacts eyes, flush them thoroughly with water. Remove solvent-saturated clothing. If vapors cause light-headedness, go to fresh air. When liquid is handled or applied at an air-exhausted workbench, wear approved gloves, and goggles or face shield. When liquid is handled or applied at an unexhausted workbench, wear approved respirator, gloves end goggles or face shield. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for more information.

16. CLEANING COMPOUND, ENGINE GAS PATH

MIL-PRF-85704

MIL-PRF-85704 Engine Gas Path Cleaning Compound may cause skin and eye irritation. Use eye protection and gloves when handling this material. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

17. METHANOL

O-M-232

Methanol (methyl alcohol) is toxic and flammable. Avoid open sources of ignition. PPE: gloves, goggles Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.


Change 5 xiii/(xiv blank)

HAZARDOUS MATERIALS WARNINGS (Cont) Index Material Warning 18. LAPPING COMPOUND

MIL-L-17862

Lapping compound may cause eye and skin irritation. PPE: gloves and goggles. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

19. COMPRESSED AIR

Compressed air used for cleaning can create airborne particles that may enter the eyes. Use approved goggles, face shield and hearing protection when using compressed air for cleaning, cooling or drying. Air pressure shall not exceed 30 psig. Compressed air shall not be directed towards self or other persons.

20. LEAK DETECTION COMPOUND

LEAK-TEC 372

Leak-Tec 372 detection compound is a skin and eye irritant. Avoid contact. Wear rubber gloves and chemical splash goggles. Consult the applicable Material Safety Data sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

21. SYNTHETIC CERAMIC BINDER AND FILLER

SAUEREISEN #29

Sauereisen #29 Synthetic ceramic binder and filler is flammable and may be irritating to the skin, eyes and respiratory tract. Overexposure can cause headache dizziness or coughing. Long-term overexposure can damage the liver, kidney and blood. Keep away from all sources of ignition. Wear butyl rubber gloves and chemical splash goggles. Approved ventilation is required. Consult the applicable Material Safety Data sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.

22. CORROSION INHIBITIVE SEALING AND

COATING COMPOUND MIL-PRF-81733, ALL TYPES

MIL-PRF-81733 Corrosion inhibitive sealing and coating compound is flammable and may contain chromate compounds that are suspected carcinogens. Avoid contact with skin and eyes. Avoid breathing vapors. Wear gloves and safety glasses. Consult the applicable Material Safety Data Sheet (MSDS) and local Occupational Safety and Health (OSH) regulations for additional information.


Change 4 1-1

SECTION I

INTRODUCTION 1-1. GENERAL. 1-2. This manual is one of a set of 17 separate manuals that compose the organizational main-tenance instruction manual for model HH-1N/UH-1N helicopter manufactured by Bell Helicopter Textron, Fort Worth, TX. The needs of the maintenance specialist have been the deter-mining factor in preparing these manuals which are tailored to the systems of the helicopter. Each component of the helicopter, therefore, is covered according to its function or purpose in relation to a system, regardless of whether the component is hydraulic, electrical, electronic, or mechanical in nature. Components that are not a functional part of any system, or instructions not affecting a specific system or component, are covered under the appropriate manual title. 1-3. SCOPE AND ARRANGEMENT OF MAIN-TENANCE INSTRUCTION MANUAL. The manuals which compose the organizational maintenance instruction manual and their general contents are as follows:

GENERAL INFORMATION AND CONDITIONAL INSPECTIONS

NAVAIR 01-110HCE-2-1 Aircraft Description and Dimensions Access and Inspection Provisions Safety Information Stowage Information Ground Handling Servicing and Lubrication Data Emergency Procedures Torque Data Support Equipment Consumable Materials Conditional Inspections

AIRFRAME AND LANDING GEAR NAVAIR 01-110HCE-2-2

Fuselage Air Distribution System Tailboom Landing Gear

POWER PLANTS AND RELATED SYSTEMS NAVAIR 01-110HCE-2-3

Power Section Air Management System Oil Cooler System Fuel Supply System Auxiliary Fuel System

POWER PLANT GROUND OPERATION AND CONDITIONING MANUAL

NAVAIR 01-110HCE-2-3.1 Ground Operations Procedures and Limits Troubleshooting Engine Conditioning

POWER TRAIN SYSTEM NAVAIR 01-110HCE-2-4

Main Driveshaft Transmission Transmission Oil System Main Rotor Mast Assembly Transmission Drive Quills Tail Rotor Drive System

FLIGHT CONTROLS AND HYDRAULIC SYSTEMS NAVAIR 01-110HCE-2-5

Collective Pitch Control System Cyclic Control System Synchronized Elevator System Tail Rotor Control System Flight Control Hydraulic System Rotor Brake System


1-2 Change 4

MAIN AND TAIL ROTOR GROUPS NAVAIR 01-110HCE-2-6

Main Rotor Installation Tail Rotor Installation Main and Tail Rotor Tracking and Balance

UTILITY SYSTEMS NAVAIR 01-110HCE-2-7

Litter Equipment All-Weather Covers Cargo Nets Rescue Hoist Troop Seats Formation Lighting Air Transportability Winterization Heating

ARMAMENT SYSTEMS NAVAIR 01-110HCE-2-8

External Stores Support Assembly (LH/RH) BRU-20/21 A/A Bomb Ejector Racks M-60D Gun Adapter Assembly M-218 (GAU-16/A) Gun Adapter Assembly CA-513E Optical Reflex Sight GAU-17 Armament Subsystem

ELECTRONIC COUNTERMEASURE SYSTEMS NAVAIR 01-110HCE-2-9

Radar Warning System – AN/APR-39A(V)2 Countermeasures Dispensing System – AN/ALE-39 Countermeasure Set System – AN/ALQ-144 Missile Warning Set System – AN/AAR-47

INSTRUMENTS NAVAIR 01-110HCE-2-10

Instrument Panel Flight Instruments Navigation Instruments Engine Instruments Pitot-Static System Miscellaneous Instruments

ELECTRICAL SYSTEM NAVAIR 01-110HCE-2-11

DC System AC System Lighting System Caution and Warning System Engine Controls and Accessories System Miscellaneous Electrical System

AVIONICS SYSTEMS NAVAIR 01-110HCE-2-12 (UH-1N)

Communication System Navigation System Identification System Automatic Flight Control System – Electrical

AVIONICS SYSTEM NAVAIR 01-110HCE-2-12-1 (HH-1N)

Communications Systems Navigation Systems Identification System Automatic Flight Control – Electrical

WIRING DIAGRAMS NAVAIR 01-110HCE-2-13 (UH-1N)

Wiring Identification Codes Wire Replacement Data Wiring Diagrams AC and DC Power Systems Communication Schematics Navigation Schematics Component Wiring Diagrams

WIRING DIAGRAMS NAVAIR 01-110HCE-2-13-1 (HH-1N)

Wiring Identification Codes Wire Replacement Data Wiring Diagrams AC and DC Power Systems Communications Schematics Navigation Schematics Component Wiring Diagram

COMMUNICATIONS SECURITY SYSTEMS CERTIFICATION PROCEDURE

NAVAIR 01-110-HCE-2-16 1-4. ASSOCIATED AIRCRAFT MANUALS. Manuals in the maintenance instruction manual do not contain instructions for overhaul of components. Such instructions are issued as separate manuals of overhaul instructions for the individual components. Intermediate level maintenance instructions are contained in Intermediate Maintenance Manual, NAVAIR 01-110HCE-2-15. Instructions for repair of the helicopter structure are contained in Structural Repair Manual, NAVAIR 01-110HCE-3. Data necessary for obtaining replacement parts, and complete identification of parts, is contained in Illustrated Parts Breakdown, NAVAIR 01-110HCE-4 Series. To obtain these publications, refer to NAVSUP Publication 2002.


1-3

1-5. LUBRICATION AND SERVICING. 1-6. Assembly and installation lubrication and servicing requirements for systems and com-ponents covered in this manual are included as part of the normal maintenance instructions. For periodic lubrication requirement, refer to the appropriate maintenance requirements cards. For periodic servicing requirements, refer to servicing, General Information, NAVAIR 01-110HCE-2-1. 1-7. SUPPORT EQUIPMENT. 1-8. Support equipment required for main-tenance of systems and components covered in this manual is listed in table 1-1. For a complete list of support equipment, refer to support equipment, General Information, NAVAIR 01-110HCE-2-1. When an item of support equipment is not available, an approved alternate identified in the activity's Individual Material Readiness List (IMRL) may be substituted. 1-9. CONSUMABLE MATERIALS. 1-10. Consumable materials required for main-tenance of systems and components covered in this manual are listed in table 1-2. For a complete list of consumable materials, refer to con-sumable materials, General Information, NAVAIR 01-110HCE-2-1. This list is grouped by Military Specification, Military Standard, Federal Specifi-cation, and Commercial and Government Entity (CAGE) codes, with the detail item numbers ar-ranged in alpha-numerical sequence under each category, followed by the nomenclature of the item. Textual reference to a consumable item will consist of the basic name, followed by the specification or CAGE designation. 1-11. RECORD OF APPLICABLE TECHNICAL DIRECTIVES. 1-12. Table 1-3 is a list of applicable technical directives which affect instructions in this manual where applicable. Instructions are identi-fied by the technical directive number. Reference in text to technical directive numbers are for all Parts or Amendments, unless otherwise specifically noted. At a specified time following

incorporation of a technical directive, or when it is known all applicable helicopters and equip-ment have been modified, obsolete information and reference to the technical directive will be deleted from text. For a complete list of technical directives, refer to technical directives, General Information, NAVAIR 01-110HCE-2-1. 1-13. QUALITY ASSURANCE. 1-14. Quality assurance requirements are indicated in this manual by italicizing a procedural step and the legend (QA) will appear at the end of the step when an inspection is required before proceeding to the next step, or by summarizing at the end of maintenance procedure, inspections that are to be performed after completion of the procedure. 1-15. GLOSSARY OF TERMS, SYMBOLS AND ABBREVIATIONS. 1-16. The glossary of terms, symbols and abbreviations in this manual are as follows: ACCELERATION POWER SECTION ....... Power section response

from an initial value to a higher value within a designated time.

AMBIENT AIR PRESSURE .................. Barometric pressure of

the atmosphere, usually expressed in inches of mercury.

AMBIENT AIR TEMPERATURE........... Temperature of the

atmosphere, expressed in degrees Centigrade or degrees Fahrenheit.

AXIAL FLOW COMPRESSOR............ A compressor in which

the air is compressed while continuing through the power section in approximately the same direction of flow.


1-4

CENTRIFUGAL FLOW COMPRESSOR............ A compressor or stage of

compression in which the air is compressed by being flung radially outward from the axis of rotation of the compressor. This usually is the vaned-impeller type hub operating within a shroud-enclosed space.

COMBUSTION CHAMBER ................... That section of the power

section into which fuel is injected and burned.

COMPRESSOR BLADE ......................... An airfoil-shaped compo-

nent used as a means of accelerating air flow in the power section.

COMPRESSOR STAGE ......................... Each section of a com-

pressor in which the air pressure is progressively increased.

COMPRESSOR STALL .......................... An unstable air condition

within the compressor. FLAMEOUT.................. Inadvertent loss of com-

bustion. FUEL NOZZLE............. A device which atomizes

and directs fuel into a combustion chamber.

HOT START ................. Any start in which ITT

exceeds allowable limits. IGNITER ....................... An electrically operated

device which produces a spark to ignite fuel/air mixture within a com-bustion chamber.

INTERTURBINE TEMPERATURE (ITT) .............................. The temperature of the

hot gases taken between compressor turbine and power turbine.

LIGHT OFF................... Ignition of the fuel/air

mixture within the com-bustion chamber.

OVERSPEED................ A specified compressor or

engine output speed which is above the specified maximum allowable rpm.

OVER- TEMPERATURE........... Any interturbine tempera-

ture (ITT) which exceeds the maximum allowable temperature for a specific power section operating condition.

STARTER..................... An electrically operated

device used to turn the compressor for starting purposes.

TORQUEMETER.......... A device which generates

an oil pressure in propor-tion to the torque output of a power section.

TURBINE...................... A disc to which blades are

attached for the purpose of extracting energy from the expanding gases. The disc is attached to a shaft and drives the shaft when the disc is rotated by expanding gases.

AFC Airframe Change AFCU Automatic Fuel Control Unit CW Clockwise CCW Counterclockwise FCU Fuel Control Unit


Change 2 1-5

FOD Foreign Object Damage ID Inside Diameter IMA Intermediate Maintenance Activity ITT Interturbine Temperature MFCU Manual Fuel Control Unit Nf Power Turbine Speed Ng Compressor Turbine Speed N1 (Gas Generator) Nr Rotor rpm OAT Outside Air Temperature OD Outside Diameter Pa Pressure Ambient Pg Governor Reset Pressure PPC Power Plant Change Pr Regulated Pressure PSIG Pounds Per Square Inch Gage Px Enrichment Pressure Py Governor Pressure P3 Compressor Discharge Pressure P & WC Pratt and Whitney of Canada Q Torque RGB Reduction Gearbox/Combining Gearbox RPM Revolutions Per Minute SHP Shaft Horsepower Wf Fuel Flow

1-17. WARNINGS, CAUTIONS AND NOTES. 1-18. The following definitions apply to warnings, cautions and notes found throughout the manual.

WARNING

An operating procedure, practice, or condition, etc., which may result in injury or death if not carefully observed or followed.

CAUTION

An operating procedure, practice, or condition, etc., which may result in damage to equipment if not carefully observed or followed.

NOTE

An operating procedure, practice, or condition etc., which is essential to emphasize.


1-6 Change 5

TABLE 1-1. SUPPORT EQUIPMENT Nomenclature

Specification or Part No.

Manufacturer/ CAGE

Arbor 2516 87065 Bubbler Assy., Bleed Valve Adjustable

PWC70513 00198

Cable, Ambient Temperature BH21620 98869 Cable, Signal BH21830-2 98869 Cable, Torque BH21621 98869 Cleaner, Spray Type MA-1 (or equivalent) Comparator, Screw Thread #210 Series Micrometer Caliper 57163 Drift CPWA 30075 00198 Drift CPWA 30661 00198 Drift CPWA 30671 00198 Drift CPWA 30675 00198 Harness, Extension BH19139-1 Hose Assembly BH21832 Indicator, Dial (Accurate to 0.00001 inch)

Kit, TCU Adjustment 18D9044 96916 Multimeter (or equivalent)

AN/PSM-6A or TS-325B/U or Simpson Model 260

95325

Probe, Ambient Temperature BH21720 98869 Puller CPWA 30046-61 00198 Puller CPWA 30046-62 00198 Puller CPWA 30046-64 00198 Puller CPWA 30646 00198 Puller CPWA 30676 00198 Puller CPWA 30748 00198


Change 5 1-7

TABLE 1-1. SUPPORT EQUIPMENT (Continued) Nomenclature

Specification or Part No.

Manufacturer/ CAGE

Puller CPWA 30833 00198 (Useable, Superseded by CPWA33044) Puller CPWA 33044 00198 (Useable, Superseded by PWC32810) Puller PWC32810 00198 (Supersedes CPWA33044) Pusher CPWA 30810 00198 Sling, Lifting CPWA 30804-50 00198 (Superseded by PWC 70079, but usable) Sling, Lifting PWC 70079 00198 Support CPWA 30670 00198 Tester, Barfield Transducer, Torque C8207 Wrench CPWA 30857 00198 Wrench

T101588


1-8 Change 4

TABLE 1-2. CONSUMABLE MATERIALS Nomenclature Specification or Part No. Acetone ASTM D329 Adhesive No. 4 (91427) Adhesive, Sealant, Silicone, Type I MIL-A-46106 Binder, Ceramic Sauerreisen No. 29 (80703) Cleaning Compound, Aircraft Surface, Alkaline Waterbase

MIL-PRF-87937

Cleaner, Gas Path B and B 3100 (21361) Cloth, Abrasive, Crocus ANSI-B74.18 Drycleaning Solvent, Type II MIL-PRF-680 Fluid, Calibration, Type II MIL-PRF-7024 Fluid, Checking Leak Tec 372 (03530) Grease, Pneumatic Systems SAE AMS-G-4343 Lapping Compound MIL-L-17862 Lubricant PIastilube No. 3 (02307) Methyl Alcohol O-M-232 Oil, Lubricating, Synthetic Base MIL-PRF-23699 Petrolatum VV-P-236 Retaining Compound, Grade A MIL-S-22473 (ASTM D5363) Sealing Compound, DC-4 DC-4 (71984) Sealing Compound, Temperature Resistant, Class B2

AMS-S-8802

Sealing Compound, Type II-1/2 MIL-PRF-81733 Sheathing, Heat Shrinkage, Silicone Rubber RT-876 (06090)


Change 4 1-9

TABLE 1-2. CONSUMABLE MATERIALS (Continued) Nomenclature Specification or Part No. Stone, Alocite Resinoid, Grade AF3-JB CAGE 10646 Tubing, Clear Plastic MIL-P-22296 Turbine Fuel, Aviation Grades JP-4/JP-5 MIL-DTL-5624 Wire, Safety or Lock, Corrosion Resistant Steel MS20995C22


1-10

TABLE 1-3. RECORD OF APPLICABLE TECHNICAL DIRECTIVES Type/ Number

Date

Title/ECP

Change/Revision Date

AFC 77 1 May 1973 Modification of Throttle System Flight

Idle Stop (ECP 587) –

PPC 8 Feb 1972 Incorporation of Oil Scupper Drain

for Output Shaft (ECP 28) –

PPC 9, Rev. A

Jun 1972 Compressor Wash Manifold, Incorporation of (ECP 58)

–

PPC 24, Amend. 1

4 Aug 1972 T5 Limiter, Partial Deactivation of –

PPC 25 Jul 1973 Introduction of Sleeve Connector for

Governor Heated Tubes –

PPC 26, Amend. 1

Apr 1975 Modification of Reduction Gearbox Section Oil System (ECP 56R1C1)

–

PPC 33, Amend. 1

Aug 1976 Compressor Bleed Valve, Improved Maintainability TO (ECP 81C1)

–

PPC 42 Nov 1975 Improved Fasteners for Fuel Control

and Pump (ECP 82R1) –

PPC 44 Oct 1976 Introduction of CV into CL Shaft

Sealing Air Supply (ECP 63) –

PPC 45 Aug 1976 Removal of Power Section T5

Limiting Function (ECP 114) –

PPC 51 25 Apr 1977 T5 Thermocouple Integral Harness,

Introduction of –

PPC 56 25 Jul 1979 P3 Compressor Delivery – PPC 57 14 Jun 1979 Corrugated Stainless Steel Gaskets,

Introduction of –

PPC 61, Rev. A

1 Jun 1982 Oil to Fuel Heat Exchanger Improved Thermal Element

–

PPC 65 1 Apr 1982 Engine Torque Control Oil Pressure

Tubes, Revised Routing –


Change 5 1-11/(1-12 blank)

TABLE 1-3. RECORD OF APPLICABLE TECHNICAL DIRECTIVES (Continued) Type/ Number

Date

Title/ECP

Change/Revision Date

PPC 70 Dec 1982 Torque Control With Improved

Damping (ECP 166R1) –

PPC 76, Rev. A

Mar 1987 Detachable T5 Terminal Block –

PPC 77 12 Oct 1988 Fitter, P3 Compressor Delivery –

Introduction of Spring Loaded Filter (ECP 178R1)

1 Oct 1992

AFC 263 Amend. 3

14 Jul 1993 Single Engine Heat/Defrost Capability Modification (RAMEC PNCLA 19-90)

30 Aug 1994

7 Mar 1996 Introduction of Improved Fuel Manifold

Transfer Tube (ECP T400-10) 30 Nov 1999

– 17 Mar 1994 Improved T5 Limiter

Thermocouple (ECP T400-8)

15 Feb 2002

AFC 339 Amend. 1

30 Apr 2001 HH/UH-1N Tail Rotor Drive Shaft System (ECP 1710)

1 Feb 2004

PPC 85 15 Jan 2005 T400 Compressor Delivery Air Pressure Insulated

Tube Assembly, Compressor Air Filter Element, and Compressor Air Filter Cover, Replacement of

1 Apr 2006

PPC 86 31 Jan 2006 T400 Compressor Air Bleed Valve Assembly,

Replacement of 1 Apr 2006

AFC 363 15 Feb 2006 Dual Torque Indicator, Installation of 1 Apr 2006


2-1

SECTION II

SYSTEM DESCRIPTION 2-1. POWER PLANT PACKAGE. 2-2. The helicopter is powered by a T400-CP-400 twin power section turboshaft power plant package. Related systems include cowling, firewalls, mounts, controls, air management, fire extinguishers, fuel and oil systems. 2-3. POWER SECTION. 2-4. The power plant package consists of two identical power sections and a reduction gearbox. Power sections drive through separate, functionally identical, reduction gear trains in the gearbox and a sprag clutch in each gear train allows disengagement of an inoperative power section. A gas generator in each power section, consisting of a compressor, combustion chamber and turbine, delivers expanding combustion gases to drive a power turbine. Each power turbine drives its power section gear train through shafting. Each power section has its own independent lubricating oil system, which lubricates power section and reduction gear train bearings. A third oil system lubricates gearbox output shaft bearings. (See figure 2-1.) The torque control unit on the reduction gearbox equalizes power section torque outputs and limits their sum. An accessory gearbox on each power section front end supports fuel control units and pump and a starter generator. Lubricating oil pressure pump and two scavenge pumps are housed inside the accessory gearbox. A third scavenge pump is mounted on the accessory gearbox cover.

NOTE

To enable use of standard terminology in this manual, individual power sections will be referred to as Power Section 1 (left) and Power Section 2 (right). (See figure 2-2.)

2-5. POWER LEVER (Ng) CONTROLS. 2-6. The power lever controls system con-sists of two parallel mechanical linkage sub-systems, connecting the dual throttle control mechanisms of the collective stick and jackshaft assembly to the manual fuel control units on the power sections. The linkages extend aft from the collective jackshaft, under the cabin deck between the BL 14 beams, then up inside the pylon support, and through the cabin roof into the inlet fairing ahead of the engine accessory gearboxes. Protective covers are provided to prevent contamination, binding or jamming of the power lever control tubes due to foreign objects in the control tube in the power section area. A flight idle stop, with a solenoid for electrically controlled release, is provided in each subsystem. 2-7. OPERATION. The power control linkages are actuated by two throttle control twist-grips on each of the collective pitch control sticks. A friction control for each grip is provided on the pilot stick only. The upper grip is marked ENGINE 1 and controls gas generator (Ng) rpm for the left-hand power section. The lower grip, marked ENGINE 2, controls the right-hand power section. Both grips are also marked with arrows showing direction of movement to INCREASE rpm. When the grip is turned to right, rpm will be reduced until linkage contacts the flight idle stop (at 61±2 percent Ng). Actuation of the IDLE STOP REL switch (on pilot stick) to ENG 1 or ENG 2 will retract the solenoid plunger from the corresponding stop for approximately 5 seconds to allow moving the grip and decreasing rpm below flight idle.


2-2

Figure 2-1. Power Section Lubrication System Schematic


2-3

Figure 2-2. Power Plant Package Orientation 2-8. DROOP COMPENSATOR (Nf) CONTROLS. 2-9. The droop compensator control system consists of mechanical linkage from the col-lective pitch control system through a compen-sating cambox, an electro-mechanical linear actuator, and a jackshaft to the engine governors controlling the power turbine (Nf) rpm of the power sections. Protective covers are provided at service deck to prevent con-tamination, binding or jamming of the droop compensator control tubes due to foreign objects in the control tube housing. 2-10. OPERATION. The linear actuator can be retracted or extended by use of the RPM INCR-DECR (beep) switches on the collective control sticks, allowing remote setting of the power turbine (Nf) rpm range. Movements of collective controls will be transmitted through

the compensating cambox changing the governor control to accommodate need for increased or reduced power as the main rotor blades change pitch. Linkage includes a bellcrank with a shearable rivet, to allow emergency use of collective controls in event of accidental jamming of droop compensator controls. 2-11. AIR MANAGEMENT SYSTEM. 2-12. The air management system (figure 2-3) provides inlet air to each engine power section and carries away exhaust gases. The system consists of twin series of ducts and valves, within the engine cowling and extending aft from the air inlet fairings above each power section and includes the exhaust ducts and the induction baffle installations. The control valve in each air passage


2-4 Change 3

is located downstream from the induction baffle, and has an electrical actuator controlled by a three position ON-AUTO-OFF switch marked PART SEP and ENG NO. 1 or NO. 2. The electrical circuits are connected through breakers ENG 1 PART SEP and ENG 2 PART SEP to the 28 VDC essential bus, with interconnections to caution panel PART SEP OFF and through emergency switches to the fire extinguishing system and the engine low rpm warning system. 2-13. OPERATION. During normal operating conditions air is drawn in through inlet fairing by combined action of engine compressor and exhaust flow through the ejector, plus the ram effect of any forward movement of the heli-copter. Air flow gains velocity as the inlet duct area decreases, thereby increasing the momentum of any particles of dust, ice or other foreign materials. The control valve is normally open, allowing part of the air stream to pass through the out of the ejector, carrying away most foreign particles by their own inertia. The remainder of air passes down through a screened opening into the induction plenum area and into the screened engine intakes. When the PART SEP switch for an engine power section is ON, the system will be in the condition described above. When the switch is OFF, the control valve will be closed by extension of the actuator, caution panel segment PART SEP OFF will be illuminated, and all inlet air will be routed through the engine power section. When the switch is in AUTO position, the valve actuating circuit is interconnected through the emergency switch to the ENGINE LOW RPM warning and fire extinguishing systems and is responsive to conditions to those systems. The FIRE PULL handle will override either AUTO or ON position of AIR PART SEP switch. In AUTO position, the control valve will be normally open, but will close in event of the engine losing power or if the FIRE PULL handle is actuated. Valve closing will cause the PART SEP OFF caution panel to illuminate. When visible moisture is evident at temperatures below 40°F (4°C), the AUTO position should be used. 2-14. OIL COOLER SYSTEM. 2-15. The three separate oil systems of the engine power sections and the reduction

(combining) gearbox are connected by external hoses to three radiator type coolers located aft of the engine. The upper cooler is a dual unit, serving both the engine gearbox and the transmission oil system. The coolers are mounted in a structural support, and are connected by air ducts to two blowers mounted on and shaft driven by the reduction gearbox. Drain lines with manual valves are provided for all engine-to-cooler lines. 2-16. ENGINE MOUNTS. 2-17. The engine reduction gearbox is sup-ported on a tripod and a bipod. The accessory gearboxes are supported on two vertical tubes interconnected through bellcrank type fittings by a cross tube. The tripod and bipod have steel tube legs, with bearing rodends for attachment in deck fittings and with forks for attachment to bearing fittings on the gearbox. The forward mount vertical tube rodends are attached in fittings on gearboxes and in the crank fittings, which are pivoted in deck fittings with movement restricted by block stops. 2-18. ENGINE COMPARTMENT FIRE EXTIN-GUISHER INSTALLATION. 2-19. The engine compartment is provided with two fire extinguisher containers interconnected to discharge manifolds and tubes located below and in front of each power section. The containers are spherical steel assemblies charged with freon and nitrogen at approximately 600 psi pressure. Each container has two discharge outlets equipped with electrically actuated cartridges, a guarded pressure gage, and a fill and thermal relief fitting connected to a red visual discharge indicator disc. A pressure temperature correction table is provided as a decal on the container. Fire detector elements mounted on the engine deck and forward firewall are connected to warning lights in the FIRE 1 PULL and FIRE 2 PULL T-handles located on the instrument panel.

NOTE

The extinguishing agent is noncorro-sive and does not cause any require-ment for special cleaning or treatment of lines and compartment after use.


2-5

Figure 2-3. Air Management System Schematic


2-6 Change 3

2-20. OPERATION. If fire occurs in an engine compartment, the detectors will cause a warning light to show on the T-handle for that engine section. With the FIRE EXT selector switch at MAIN, pulling the handle (FIRE 1 PULL or FIRE 2 PULL) will discharge manifold. If the other container is needed, the FIRE EXT switch should be set to RESERVE. 2-21. FUEL SUPPLY SYSTEM. 2-22. The fuel supply system is designed to resist spillage of fuel in crash impacts, reducing fire hazard in such conditions, and also has increased protection against leaks due to gunfire. All tank cells, the interconnect lines between cells, and main fuel lines to engines are self-sealing construction. Flexible hoses are used extensively instead of rigid metal tubes. All cells contain foam baffles conforming to MIL-B-83054. Doors and fittings which cover cell openings at various locations are attached to supporting structure by frangible clips or breakaway fittings, to allow cells to remain sealed if an impact causes cells to shift and break loose from structure. Certain fittings are so designed that any break would occur between two self-closing valves. A fueling valve, for use with a standard pressure nozzle (MS29520), is provided below and aft of the gravity filler on the right-hand side of the fuselage. A supply line from the valve delivers fuel into the tank cells through a dual shutoff valve on the aft interconnect. A dual float operated pilot valve, mounted in the center aft cell, controls the shutoff valve through connecting lines to prevent over filling. The pilot valve is also connected to manually actuated test valves on the fueling valve. 2-23. The fuel supply system is contained in five cells which are interconnected to act as a single tank. Three nonself-sealing cells are located aft of the pylon structure and cabin bulkheads, between the engine deck and cabin floor levels. Two self-sealing type cells are located under the cabin floor at each side, ahead of the cabin bulkhead and outboard of the main longitudinal structural beams. Each under floor cell is equipped with: a sump, a submerged electric motor driven boost pump, a flow-actuated switch connected to a caution panel to signal if pump is inoperative, a lateral baffle fitted with a flapper valve to allow front-to-rear fuel flow and an ejector type pump mounted on

the front wall and using booster pump flow to send fuel continuously back over the baffle to the rear portion of the cell to assure maximum usability of fuel in all flight positions. 2-24. The system filler is on the right-hand aft cell and incorporates a receiver with automatic fuel level shutoff for a closed circuit refueling nozzle. A defueling valve is located on the interconnecting lines directly aft of the left-hand underfloor cell. Vent lines from all cells are connected to a common line equipped with a siphon-breaker valve and leading overboard through the fuselage lower skin. Fuel quantity gage transmitters are located in the center aft cell and in front and rear compartments of the righthand forward cell. The left forward cell contains a float switch connected to the FUEL LOW caution panel. 2-25. Fuel pressure lines from boost pumps are interconnected through an electrically controlled valve, so that output of either or both pumps is available for each engine. Lines to each engine pass through an electrically controlled shutoff valve and an airframe mounted filter. Shutoff valves and directional flow check valves have internal by-pass provisions to relieve thermal expansion of trapped fuel when the system is inoperative. Each filter has internal by-pass provisions to assure flow if the filter becomes clogged, and is connected to a caution panel to give visual signal of an impending by-pass condition. 2-26. The center aft fuel cell has an access door in its rear wall. A fuel quantity transmitter is supported on brackets on inside of the door. Two float switches mounted at the same location are used only when auxiliary tanks are installed. A return line and check valve connected to the door serve the AFCU bleed lines from the engines.

NOTE

NAVAIR 01-1A-35 shall be used in conjunction with instructions of this manual when performing maintenance on fuel cells. In event of conflict between this manual and NAVAIR 01-1A-35, the latter shall take precedence.


2-7/(2-8 blank)

2-27. AUXILIARY FUEL SYSTEM. 2-28. Piping and electrical circuit connections are provided for installation of two auxiliary fuel tank cells in the cabin cargo area, increasing the total fuel capacity by approximately 300 US gallons. The bladder type auxiliary fuel cells are left-hand and right-hand assemblies, shaped like quarters of cylinders to fit against the cabin rear bulkhead and each side of the pylon support structure. Cells are secured in place by attaching nylon web straps to vertical row of studs on the bulkhead and pylon support, and by cords tied between fittings on upper end of cell and on cabin structure. Each cell has a filler cap, a pump and float switch assembly with an electrical cable and connector, and hose assemblies attached to the pump outlet and seal drain and to tank drain and vent openings. All hoses have quick-disconnect couplings for connection to airframe piping at couplings located under the floor at each side of cargo door openings. The cell drain hose has a manual drain valve; the pump discharge hose has a directional flow check valve. Below the floor, vent and drain lines pass overboard through the lower skin. The fuel lines from auxiliary cells are connected to the floor; vent and drain lines pass overboard through the lower skin. The fuel lines from auxiliary cells are connected to the main fuel system at tee fittings on the crossfeed line at front ends of underfloor cells. Electrical circuits connect each cell float switch to an AUX

FUEL LOW caution panel segment. Pumps are connected to the AUX FUEL CONT panel switches through a fuel transfer relay which is also governed by float switches mounted at two levels in the center aft cell of the main fuel system. 2-29. FUNCTION - AUXILIARY FUEL SYSTEM. Auxiliary fuel system circuits (figure 2-4) obtain power from the 28 VDC non-essential bus. When LH and RH auxiliary fuel transfer pump switches (S103 and S104) are placed ON and after approximately 30 gallons have been used, fuel will be pumped from auxiliary cells to main system. When main tank is approximately 5 gallons from full, fuel level in center aft cell actuates the upper float switch (S41), the fuel transfer relay (K33) will energize to interrupt power to pumps (B23 and B24). If switches are left in ON position, pumps will not run until fuel level drops enough to open lower float switch (S42), deenergizing transfer relay (K33) which will restore power to operate pumps. This cycle of operation will continue until fuel level in one of the auxiliary cells drops low enough to open its float switch (S105 and S106) and cause illumination of the AUX FUEL LOW caution panel segment. At this time, the empty tank can be identified by placing one pump switch (K20 or K25) OFF and observing effect on caution light. If one auxiliary still contains fuel, its pump can be operated alone until cell is empty. (Cells can be pumped singly at any time, as desirable for lateral balance.)


2-9/(2-10 blank)

Figure 2-4. Auxiliary Fuel System Schematic


3-1/(3-2 blank)

SECTION III

SUPPORT EQUIPMENT MAINTENANCE 3-1. GENERAL. 3-2. Maintenance of support equipment used in this manual is not applicable.


4-1

SECTION IV

ORGANIZATIONAL MAINTENANCE 4-1. TROUBLESHOOTING - POWER PLANT AND RELATED SYSTEMS. 4-2. DESCRIPTION. Troubleshooting procedures (table 4-1) presented in this section are provided as an aid to the mechanic in obtaining a better understanding of the T400-CP-400 power plant package and its relation to the HH-1N/UH-1N helicopter. All malfunctions of the power plant package may be classified as one of two general types: those immediately obvious, such as a power section failing to start, and those that are not obvious and if not detected in time would eventually cause damage to the power plant package. It is essential that the mechanic have a thorough knowledge of the various power plant package parameters, limits and other important details of normal power plant package performance so that a malfunction may be immediately recognized. Power section power plant package troubles are not always related to one specific cause; frequently, several causes may contribute to poor engine performance. The probable causes for any particular trouble have been listed in decreasing order of probability and each probable cause should be checked in turn until, by the process of elimination, the trouble has been isolated and corrected. 4-3. COMPRESSOR STALL. Compressor stall may occur when one or more stages of a com-pressor experiences excessive back pressure or abnormally high air flow for a given compressor speed (Ng). A breakdown in the normal flow pattern results in interstage recirculation and turbulence. Stall may occur if the compressor bleed valve is malfunctioning. Stall symptoms may be recognized as a loud popping noise (or soft explosion) or a low frequency rumble. Low frequency rumble below 75 percent Ng without parameter fluctuations would not indicate stall out fuel system resonance. Prolonged stall can result in serious overstress and/or overtem-

perature damage to the power section. A com-pressor bleed valve allows the escape of inter-stage air during low power operation and thus prevents compressor stall. Compressor bleed valve operation is completely automatic. Com-pressor stall, to the degree of being audible, except for the mild form which may occur during automatic-manual transfer, is not characteristic of the T400-CP-400 engine and should be investigated and eliminated. Stall can therefore be avoided by proper conditioning and maintenance of the power section/engine. 4-4. LOW POWER/LOW TORQUE. Low power/ low torque is a most common problem. A logical approach to the problem is generally indicative of two things; actual engine malfunctions and/or instrumentation malfunctions such as: Ng, ITT, fuel flow and torque. To ascertain actual low power/low torque, single engine lift capability should be performed. If one engine will not perform with the same indications as the actual known good engine then low power is prevalent. If lift is attained, it can be concluded instrumentation/calibration is suspect. Proceed accordingly by process of elimination until the trouble has been isolated and corrected. A procedure for adjustment of percent torque indicated to percent torque actual for reduction gearbox torquemeter is included. 4-5. TROUBLE AREAS. a. Index of Troubles. 1. Failure to Light Off (Gas Generator Not Rotating). 2. Failure to Light Off (Insufficient Gas Generator RPM). 3. Failure to Light Off (Gas Generator Rotating).


4-2

4. Lights Off But Fails to Reach Idle (Hung Start). 5. Excessive Start to Idle Time. 6. Abnormally High Interturbine Tempera-ture (Hot Start). 7. Flight Idle Speed Out of Limits (High or Low). 8. Flight Idle Speed Unstable (Fluctua-ting). 9. Uncontrolled Acceleration. 10. Failure to Accelerate Above Idle/ Excessive Acceleration Time. 11. Compressor Stall. 12. Failure to Decelerate. 13. Flameout During Deceleration. 14. Uncontrolled Deceleration (Flameout). 15. Uncontrolled Deceleration (No Flame-out). 16. Fluctuating Interturbine Temperature. 17. High Interturbine Temperature (Steady State Operation). 18. Abnormally Low Interturbine Tempera-ture. 19. No Indication of Oil Pressure (Power Section). 20. No indication of Oil Pressure (Reduc-tion Gearbox). 21. Fluctuating or Low Oil Pressure (Power Section or Reduction Gearbox). 22. High Oil Temperature.

23. High Oil Consumption. 24. Oil Transfer from Reduction Gearbox to Power Section. 25. Oil Transfer from Power Section to Reduction Gearbox. 26. Steady State Torque Splits. 27. Transient/Erratic Torque Splits. 28. Low Power/Torque. 29. High or Low Power Section Oil Pressure at Normal Operating Temperatures. 30. High or Low Reduction Gearbox Oil Pressure at Normal Operating Temperatures. 31. Engine Parameters Fluctuating. 32. Oil Dripping from Breather Lines (Power Section or Reduction Gearbox). 33. Oil Leaking from Power Section Com-pressor inlet. 34. When Engine or Reduction Gearbox Chip Detector Light Illuminates. 35. Vibration. 36. Surge During Acceleration. 37. Overspeed (Nf). 38. Overspeed (Ng). 39. Inability to Switch from AFCU to MFCU. 40. Fuel Leakage from AFCU/Pump Drain. 41. High Nf Speed. 42. Excessive Ng Increase During Cross-over From AFCU to MFCU. 43. Fuel Filter Caution Panel Illuminated.


4-3

44. Fuel Boost Caution Panel Illuminated. 45. Fuel Shutoff Valve Inoperative. 46. Fuel Interconnect Valve Inoperative. 47. No Flow When Pressure Fueling. 48. Fueling Flow Not Stopped by Test Valve Use. 49. No Fuel Transfer from One Auxiliary Tank. 50. No Fuel Transfer from Either Auxiliary Tank.

51. Fuel Overflows Main Tank Vents During Transfer. 52. Auxiliary Tank Collapsing During Transfer. 53. Low Speed Rumble. 54. High Power Rumble. 55. Fails to Limit Torque. b. Procedures. (Refer to table 4-1.)


4-4

TABLE 4-1. TROUBLESHOOTING Item Trouble Probable Cause Troubleshooting Corrective Action

(a) Check circuit breaker. 1. Reset or replace circuit breaker.

(b) Check power supply 23.5

to 29.5 VDC. 1. Repair or

replace faulty item.

(c) Check all starter-

generator connections and leads.

1. Repair or replace faulty components.

(d) Check start control relay

for connections and condition.

1. Replace relay.

1 Failure to Light Off (Gas Generator Not Rotating)

(1) Electrical supply to starter.

(e) Check reverse current relay for connections and condition.

1. Replace relay.

(2) Starter-generator. (a) Listen for sound of rotation of starter and verify no Ng tachometer drive rotation.

1. Replace starter-generator.

(3) Seized compressor. (a) Listen for compressor rotation.

1. Replace power section.

(1) Insufficient voltage. (a) Check electrical supply.

1. Replace or

adjust defective unit.

(a) Check max. attainable Ng.

(14% in 13 – 15 seconds)


(2) Starter-generator.

(b) Check tachometer-generator.

1. Replace faulty component.

2 Failure to Light Off (Insufficient Gas Generator RPM)

(3) Compressor rotor rubbing.

(a) Listen for scraping noise during compressor rotation.


(a) Check electrical supply to system.

1. Repair circuit. 3 Failure to Light Off (Gas Generator Rotating)

(1) Ignition system.

(b) Perform ignition system check.

1. Replace unit if found defective. (Ignition Exciter, Cables and Spark Igniters.)


4-5

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action

(2) Automatic fuel control unit.

(a) Carry out power section Manual-Mode start. Refer to Notes 1 through 7 for additional instructions.

1. Replace auto-matic fuel control if found defective.

(3) Blocked airframe fuel supply.

(a) Check airframe shutoff valves, and fuel system.

1. Replace detective components.

(a) Perform wet motoring run and verify fuel drainage from combustion chamber drain valve and flow divider. If none, disconnect fuel flow divider connection and repeat wet motoring run checking for fuel flow. Fuel flow indicates defective flow divider.

1. Replace flow divider.

3 (Cont)

(4) No fuel flow-possible defective fuel system component.

(b) If no fuel flow, AFCU, MFCU or engine driven fuel pump is suspect.

1. Replace detective units in turn.

(1) Improper starting procedure.

(a) Refer to NAVAIR 01-110HCE-1.

1. Employ proper starting procedure.

(2) Defective flow

divider. (a) Check for fuel or fuel mist

from drain line during hung start.

1. Change defective flow divider.

(3) P3 filter clogged. (a) Remove filter element, reinstall filter housing and recheck engine.

1. If operation normal, replace P3 filter.

1. If start and run

are normal, repair leak in pneumatic sense line if found.

4 Lights Off But Fails To Reach Idle (Hung Start)

(4) Loose, broken, open pneumatic sense lines or water in AFCU.

(a) Perform pneumatic leak check. Refer to Notes 1 through 7 for additional instructions.

2. Perform power section manual mode start and run at idle for 5 minutes.


4-6


(5) AFCU malfunction. (a) Pneumatic contamination. Refer to Notes 1 through 7 for additional instructions.

1. Remove P3 orifice and inspect for contamination. If none is found, replace AFCU.

4 (Cont)

(6) Ice in the Pg or P3 pressure lines at temperatures 32°F (0°C) or lower.

(a) Perform power section manual mode start.

1. If start is normal, run 5 minutes and switch to automatic mode.

(1) Leaking pneumatic

sense lines to AFCU.

(a) Carry out power section Manual-Mode start. If time to idle is normal, check pneumatic lines and connections. Refer to Notes 1 through 7 for additional instructions.

1. Repair all leaks.

(2) P3 filter clogged. (a) Remove filter element, reinstall filter housing and recheck start to idle time.

1. If start to idle time is within limits, replace filter.

(3) AFCU. (a) Pneumatic contamination. Refer to Notes 1 through 7 for additional instruction.

1. Remove P3 orifice and inspect for contamination. If none is found, replace AFCU.

5 Excessive Start To Idle Time

(4) Defective engine driven fuel pump.

(a) Replace suspect fuel pump with known good fuel pump.

1. Recheck start.

6 Abnormally High Interturbine Temperature (Hot Start)

NOTE

At altitudes above sea level and temperatures above 59°F (15°C), hotter than normalstarts may be experienced. Provided that the starting temperature limits are notexceeded, starts within the Hot Start Zone are not necessarily sufficient cause to warrant performance of troubleshooting. However, if an engine or airframeabnormality is suspected, troubleshooting should be performed. Temperaturesexceeding 1090°C (1994°F) require Conditional Inspection.

(1) Low voltage. (a) Check power supply 23.5 to 29.5 VDC.

1. Replace faulty item.


4-7

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action 6 (Cont)

(2) Improper starting technique.

(a) Refer to NAVAIR 01-110HCE-1.

1. Employ proper starting technique.

(3) ITT indicating

system. (a) Verify accuracy of

system. 1. Replace faulty

components.

(4) Incorrect control linkage rigging.

(a) Verify airframe to power plant rigging.

1. Adjust control linkage.

(5) Combustion chamber drain valves and dump valve.

(a) Carry out wet motoring run and verify drainage from drain valves.

1. If none from either or both remove and clean valve(s).

(6) Starter-generator. (a) Not able to attain start speed.


(a) Check for adequate

power and circuitry.


(7) Insufficient power to ignition exciter unit.

(b) Check both ignitors for firing.


(8) Faulty spark igniter. (a) Functional check. 1. Replace, if defective.

(9) AFCU malfunction. (a) Pneumatic contamination. 1. Remove P3

orifice and inspect for contamination. If none is found, replace AFCU.

(1) Indicator system. (a) Check accuracy of

indicator system.


(2) Airframe to power plant rigging out of adjustment.

(a) Consult aircraft rigging procedures.

1. Adjust rigging.

7 Flight Idle Speed Out of Limits (High or Low)

(3) (Idle speed lower than limits.) Pneumatic sense lines pressure leakage.

(a) Apply leak checking solution to pneumatic lines and connections. Refer to Notes 1 through 7 for additional instructions.



4-8


(1) Instrument or tachometer generator.

(a) Verify accuracy of system.


(2) Airframe linkage loose/worn.



(3) Fuel flow

transmitter. (a) Check for fluctuations in

Manual-Mode. 1. Replace fuel

flow transmitter.

CAUTION

Assure throttle is at flight idle before switching from automatic to manual. (4) AFCU. (a) Change to Manual-Mode.

Steady Ng indicates that AFCU is suspect. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.

8 Flight Idle Speed Unstable (Fluctuating)

(5) Ice in the Pg or P3 pressure lines at temperatures 32°F (0°C) or lower.

(a) Perform power section Manual-Mode start.

1. If start is normal, run 5 minutes and switch to automatic mode.

(1) Airframe or

interconnect linkage disconnected.

(a) Check linkage. 1. Connect linkage.

1. Replace defective or missing parts.

9 Uncon- trolled Accelera- tion

(2) AFCU splined coupling damaged or missing or AFCU faulty.

(a) Check for steady Ng in Manual-Mode start. Remove and inspect AFCU end AFCU couplings for damage or excessive wear. Refer to Notes 1 through 7 for additional instructions.

2. Replace AFCU.

CAUTION

Assure throttle is at flight idle before switching from automatic to manual.

(3) Nf governor malfunction.

(a) Change to Manual Mode. Steady Ng/Nf indicates governor is suspect.

1. Replace faulty Nf governor.

(4) Ice in Pg line. (a) Perform resistance check on Pg heater.

1. Replace faulty heater tube.


4-9

TABLE 4-1. TROUBLESHOOTING - (Continued} Item Trouble Probable Cause Troubleshooting Corrective Action

(1) Airframe to power plant linkage out of adjustment.

(a) Inspect Ng linkage. 1. Adjust or replace faulty item.

(2) Loose, broken, open pneumatic sense lines or water in AFCU.

(a) Remove ITT limiter cap. Perform power section Manual-Mode start and run at idle for 5 minutes.

1. If start and run are normal, repair leak in pneumatic sense line if found. Attempt Auto-Mode start. If problem still exists, check for pneumatic leaks.

1. Remove

obstruction.

(a) Check P3 line and fuel control P3 orifice for obstruction.

2. Clean P3 orifice if possible. If trouble persists, replace AFCU.

(3) Blockage in P3 system.

(b) Remove filter element, reinstall housing and recheck idle speed.

1. If idle speed is within limits, install new filter element.

(4) Pneumatic sense

lines leakage.

(a) Perform sense line static pressure leak check.


10 Failure to Accelerate Above Idle/ Excessive Acceleration Time

(5) Defective AFCU. (a) Check for proper operation in Manual Mode. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.

(1) Compressor bleed valve.

(a) Perform engine run. Check proper closing with water bottle.

1. Replace if suspect.

(2) Compressor damage or erosion.

(a) Inspect first stage compressor blades.

1. Replace engine.

(3) Dirty compressor. (a) Check for accumulation of dirt.

1. Perform engine wash.

11 Compressor Stall

(4) Detective AFCU. (a) Check for proper operation in Manual Mode. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.


4-10


(a) Surge damper valve malfunction.

1. Repair or replace as necessary.

11 (Cont)

(5) Compressor stall or loud bang on fuel control mode change.

(b) Crossover linkage out of adjustment.

1. Adjust crossover linkage.

(a) Consult aircraft rigging

procedures.

1. Repair and/or adjust linkage.

(1) Airframe to power plant linkage disconnected, out of adjustment or failure.

(b) Verify proper installation of interconnect linkage. Check condition of spring and assure spacer is not installed backwards.

1. Correct installa-tion. Replace damaged parts as necessary.

(2) AFCU. (a) Check P3 at bottom of AFCU for bleed air.

1. Clean orifice.

CAUTION

Assure throttle is at flight idle before switching from automatic to manual. (b) Check for proper

operation in Manual-Mode. Proper operation in Manual-Mode indicated faulty AFCU. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.

12 Failure To Decelerate

(3) Fuel surge dampener.

(a) Check that dampener slides freely in bore of housing.

1. Repair or replace with fuel accumulator.

(1) Throttle control linkage.

(a) Check flight idle stops. 1. Adjust/replace flight idle solenoid.

13 Flameout During Deceleration

(2) Defective fuel surge dampener/accumu-lator.

(a) Check that dampener moves freely inside housing.

1. If dampener does not move freely, replace surge dam-pener/replace accumulator.

(3) Defective flow

divider. (a) Check dump valve for

drainage or leakage.


(4) AFCU. (a) Perform engine run in Manual Mode. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.


4-11


(1) No fuel. (a) Check fuel supply. 1. Service helicopter fuel system.

14 Uncontrolled Deceleration (Flameout)

(2) Blocked airframe fuel supply.

(a) Check airframe shutoff valves, and fuel system.

1. Replace defective components.

(3) Fuel system

component. (a) Perform wet motoring run

and verify fuel drainage from combustion chamber drain valve and flow divider. If none, disconnect fuel flow divider connection and repeat wet motoring run checking fuel flow, which indicates defective flow divider.


(b) If there is no fuel flow at flow divider, isolate faulty power section system components. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU, MFCU and/or engine driven fuel pump, as required.

15 Uncontrolled Deceleration (No Flameout)

CAUTION

Assure throttle is at flight idle before switching from automatic to manual.

(1) Leaking or blocked pneumatic sense lines to AFCU.

(a) Check engine in Manual-Mode. If normal, apply leak checking solution to pneumatic lines and connection.


(2) P3 filter blocked. (a) Remove filter element, reinstall filter housing and recheck engine operation.

1. If uncontrolled deceleration is eliminated, install new filter element.

(3) AFCU. (a) If no leaks found in

preceding action, AFCU is suspect. Refer to Notes 1 through 7 for additional instructions.

1. Replace AFCU.


4-12


(a) Check wires for loose or faulty connections.

1. Repair or replace as required.

(1) ITT terminal block.

(b) Visually check terminal pods for cracks or missing ceramic.


CAUTION

Assure helicopter wiring harness terminals do not contact any portion of power section ITT lug shield or gas generator case after retaining nuts are torqued.

(2) Instrument or loose

connection. (a) Check all connections for

security and cleanliness. Check accuracy of instrument.

1. Replace instrument if found defective.

(3) ITT limiter circuit malfunction.

(a) Pull ITT circuit breaker and observe whether fluctuation continues.

1. Replace faulty unit in circuit.

(4) Automatic Fuel System Component.

(a) See Engine Parameters Fluctuating (item 31).

16 Fluctuating Interturbine Temperature

(5) Internal ITT harness. (a) Accomplish loop and insulation resistance check.

1. If defective, replace power section.

(1) ITT bias. (a) Accomplish ITT bias check.

1. Adjust or replace ITT limiter component if defective.

17 High Interturbine Temperature (Steady State Operation)

CAUTION


(2) Instrument reading

in error. (a) Verify as required. 1. Replace faulty

instrument.

(3) P3 line gasket, fuel nozzle gasket deterioration.

(a) Inspect. 1. Replace defective gasket/gaskets.

(4) ITT terminal block ceramic cracked or loose terminal posts.

(a) Verify inspect. 1. Repair terminal block and check loop resistance.


4-13


(a) Check piston for freedom of movement.

1. Replace bleed valve if piston movement restricted.


(b) Perform functional check utilizing bubbler bottle.

1. Replace as required.

(6) Dirty compressor. (a) Visually inspect. 1. Perform engine wash.

17 (Cont)


(a) Remove inlet screen and inspect compressor inlet blades.


(1) Instrument or leads. (a) Verify accuracy of instruments and check all leads for security and cleanliness.

1. Replace or repair faulty item.

CAUTION


(2) ITT bias. (a) Accomplish ITT bias

check. 1. Adjust or

replace ITT limiter as necessary.

18 Abnormally Low Interturbine Temperature

(3) ITT harness. (a) Perform loop and insulation resistance check.

1. Replace power section if ITT harness found defective.

(1) Low oil level.

(a) Check oil level. 1. Service system.

(2) Instruments or lines.

(a) Verity accuracy of instrument and integrity of sense lines.

1. Repair or replace faulty system.

19 No Indication of Oil Pressure (Power Section)

(3) Oil pump. (a) Inspect filter(s) for blockage or metallic chips.

1. Replace power section and reduction gearbox.


4-14 Change 4

TABLE 4-1. TROUBLESHOOTING - (Continued)

Item Trouble Probable Cause Troubleshooting Corrective Action 19 (Cont)

(3) (Cont) (b) Verify oil pump output. 1. If no positive indication of oil pressure, replace power section and reduction gearbox.

(1) Low oil level. (a) Check oil level.

1. Service system.

(2) Instrument or lines. (a) Verify accuracy of instrument and condition of sense lines.

1. Repair or replace faulty item.

(a) Verify oil pump output. 1. Replace reduction gearbox.

(b) Verify return from oil

cooler.

1. Replace oil cooler.

20 No Indica-tion of Oil Pressure (Reduction Gearbox)

(3) Oil pump.

(c) Inspect filter for blockage or metallic chips.

1. Replace reduction gearbox.

(1) Low oil level(s). (a) Check oil level(s). 1. Service

system(s).

(a) Verify accuracy. 1. Replace faulty instrument.

(b) Check power supply for

stability and accuracy. 1. Repair/replace

faulty component.

(c) Verify correct oil pressure

transmitter. 1. Install correct oil

pressure transmitter.

(2) Instrument.

(d) Check for restrictor in oil pressure transmitter.

1. Install restrictor.

(e) Confirm fluctuation with direct pressure reading gage on power section or reduction gearbox oil pressure system.

1. Replace instrument/oil pressure transmitter if fluctuation not confirmed.

21 Fluctuating or Low Pressure (Power Section or Reduction Gearbox)

(3) Filter. (a) Inspect filter(s) for blockage or metallic chips.

1. Replace power sections and reduction gearbox if metallic chips found.


Change 4 4-15

TABLE 4-1. TROUBLESHOOTING - (Continued)

Item Trouble Probable Cause Troubleshooting Corrective Action

1. If on power section, accomplish oil check and adjustment

(a) Use direct reading gage on power section or reduction gearbox inlet line.

2. If on reduction gearbox with PPC No. 26 incorporated, accomplish oil pressure check and adjustment. If PPC No. 26 is not incorpo-rated, replace gearbox.

(4) Pressure regulating valve.

(b) Check for metered elbow to No. 1 bearing oil pressure line.

1. Replace as required.

21 (Cont)

(5) Oil cooler malfunction.

(a) Verify oil return from cooler.


(6) Internal power

section or reduction gearbox oil system discrepancy.

(a) Accomplish previous troubleshooting steps and use direct pressure reading gage on oil pressure system.

1. If discrepancy confirmed on direct pressure gage, replace twin-pac.

(1) Low oil level(s). (a) Check oil level(s). 1. Service

system(s).

(2) Indicator system. (a) Verify accuracy. 1. Replace faulty indicator.

(3) Oil cooler. (a) Check for air obstructions

or oil side by-pass valve leakage.

1. Clean or replace faulty unit or boot.

22 High Oil Temperature

(4) Blower. (a) Check blower operation.

1. Replace blower.

23 High Oil Consumption

(1) Excessive oil level power section or reduction gearbox.

(a) Lower oil level in power section or reduction gearbox. Minimum power section level is at add 1 qt. line. Minimum reduction gearbox level is at bottom of green band.

1. Operate twin-pac and recheck oil consumption.

(2) Lines and seals. (a) Check for leaks. 1. Repair leaks.


4-16 Change 4


1. For power section, replace accessory gearbox breather carbon seal. If still dripping, replace power section.

23 (Cont)

(3) Overboard breather. (a) Check for overboard breather line dripping oil.

2. If on reduction gearbox, replace output seal.

(4) Oil-to-fuel heater

internal leakage.

(a) Check for oil in fuel. 1. Replace heater.

(5) Defective labyrinth seal.

(a) Check intake and exhaust area for traces of oil.

1. Assure vent breather is not clogged before replacing power section.

(1) Blocked or restricted

breather line.

(a) Check breather line for blockage or restriction.

1. Clean or replace breather line.

(2) Blocked or small size P3 metering tee orifices.

(a) Remove and clean P3 metering tee fittings on reduction gearbox. Inspect diameter of orifice and assure it is 0.040 to 0.045 inches diameter.

1. Replace small sized orifices.

(a) Check for P3 leakage in line to carbon seals.

1. Correct leakage; if problem still exists, replace reduction gearbox.

24 Oil Transfer From Reduction Gearbox To Power Section

(3) P3 leakage in line to carbon seals.

(b) Verify check valves installed properly.

1. Install check valves correctly.

(1) Torquemeter cover

preformed packings.

(a) Check and verify oil transfer.


25 Oil Transfer From Power Section To Reduction Gearbox (2) Defective preformed

packings on mating flanges of reduction gearbox.

(a) Check and verify oil transfer.


(1) Defective instru-ment/indicating system.

(a) Verify accuracy of system. 1. Repair/replace faulty component.

26 Steady State Torque Splits

(2) Leaking pneumatic sense lines.

(a) Check for loose connections.

1. Repair leaks/tighten loose lines.


Change 3 4-17


(3) Air in torque control unit bellows.

(a) Pressure fill unit (prime). Bleed TCU pressure lines. Perform single engine hover checks. Check torque required for both power sections. Refer to Notes 1 through 7 for additional instructions.

1. If TCU equalizing functional checks are within limits, see item 28 Low Power/Torque probable cause (1) and subse-quent. If not, replace TCU.

(a) Verify proper operation of

torque transmitter.

1. Align transmitter.

(b) Check torque pressure transmitter part numbers and dash number for uniformity.

1. Use identical transmitter part number and dash numbers if possible.

(4) Alignment of torque transmitter.

(c) Adjust transmitter for torque cylinder connection factor, if applicable.

1. If torque split still exists, replace reduction gearbox.

(a) Check that turbine

governors are rigged properly.

1. Rig power tur-bine governors, if required.

(5) Unequal load sharing.

(b) Eliminate torque control unit from system and verify torque outputs are equal within 4 percent.

1. Perform power turbine matching checks.

(6) Airframe rigging. (a) Check airframe to power plant rigging.

1. Adjust rigging.

26 (Cont)

(7) Blockage of air supply in Pg line from automatic fuel control to torque control.

(a) Check Pg lines for blockage.

1. Remove and clean lines.

(a) Verify accuracy of torque-meter, instrument and wiring.

1. Replace faulty components.

27 Transient/ Erratic Torque Splits

(1) Instrument/ transmitter.

(b) Verify proper operation of torque transmitter.

1. Replace faulty transmitter.


4-18


(1) (Cont) (c) Check for matching numbers on transmitters.

1. Use identical part number transmitters.

(2) Bleed valve. (a) Inspect bleed valve per

NAVAIR 02B-20AA-6-1. 1. Replace faulty

bleed valve.

(3) Air in torque control unit.

(a) Check for trapped air in equalizer.

1. Prime and bleed torque control unit.

(4) Governor orifice

blockage. (a) Perform sense line

pressure leak check. (No leakage indicates blockage.)

1. Remove and clean orifice.

(5) Gearbox torque cylinder.

(a) Verify accuracy of gearbox torquemeter cylinder.

1. Replace faulty gearbox.

27 (Cont)

(6) Blockage of air supply in Pg line from automatic fuel control to torque control.

(a) Check Pg lines for blockage.

1. Remove and clean lines.

(1) Airframe to power plant rigging out of adjustment.


1. Adjust rigging.

CAUTION


(a) Verify accuracy of ITT

instrument.

1. Replace faulty instrument.

(b) Verify accuracy of ITT bias.

1. Replace faulty ITT limiter.

1. Replace faulty external harness section if defective.

28 Low Power/ Torque

(2) Instrument, ITT and/or torque-meter.

(c) Verify continuity of ITT harness.

2. Replace power section if defect is internal.


4-19


(d) Verify accuracy of torque transmitter.

1. Replace faulty transmitter.

(2) (Cont)

(e) Verify accuracy of torque instrument.

1. Replace faulty instrument.

(a) Helicopter should be flown to sufficient altitude to become Ng limited. Maximum Ng must fall between 100 to 101 percent.

1. Adjust as required.

NOTE

Certain engines will become ITT limited prior to becoming Ng limited regardless of the altitude because of internal speed and temperature match. Assure helicopter and engine operating limits are not exceeded.

(b) If maximum Ng does not fall

between 100 to 101 percent, assuming ITT limit has not been attained, reset partial power automatic control arm maximum stop adjustment.

1. Turn adjustment CCW maximum of 1/2 turn (approximately 225 rpm) or 0.5 percent Ng up to 97.5 percent and repeat topping check.

(c) If maximum Ng, ITT or fuel

flow still cannot be attained, dirty fuel nozzles are suspected.

1. Remove fuel nozzles and clean (or replace as necessary). Repeat topping check.

(3) Maximum Ng stop out of adjustment.

(d) If maximum Ng, ITT or fuel flow still cannot be attained, AFCU is suspect.

1. Replace AFCU. Repeat topping check.

28 (Cont)


(a) Check compressor bleed valve for power section using bubbler bottle.

1. Replace compressor bleed valve if not operational.


4-20


(a) Electrically actuate cabin bleed air valve. Listen for click. If click is heard, cabin bleed air valve is operational.

1. Replace cabin bleed air valve if not operational.

(5) Customer bleed air valve.

(b) Check temperature sensor for damage.

1. Replace damaged temperature sensor.

(6) Engine bleed air

elbow. (a) Check engine bleed air

elbow for blown gasket at engine connection.

1. Replace gasket.

(7) Sticking combustion chamber drains.

(a) Check for bleed air during operation.

1. Remove, clean and install drain valve.

(8) Dirty compressor. (a) Inspect first stage blades for foreign matter.

1. Accomplish compressor wash.

(9) FOD. 1. Replace power

section.

(a) Fluctuating ITT; see Fluctuating Interturbine Temperature (item 16).

(b) Fluctuating Ng; see Compressor Stall (item 11).

(10) Automatic fuel system component malfunction.

(c) Fluctuating Nf or Q. Accomplish power turbine governor rigging.

1. Replace power turbine governor if defective.

28 (Cont)

(11) Leaking pneumatic lines, Nf governor or torque control unit.

(a) Apply leak checking solution to all pneumatic lines and connections.



4-21


CAUTION

Assure that maximum allowable output shaft speed and torque are not exceeded.

(b) Suitably blank pneumatic

tubes and oil tubes to torque control unit and repeat power/torque check; if increased power/torque is noted, torque control unit is suspect.

1. Replace torque control unit.

(11) (Cont)

(c) Nf governor is suspect. 1. Replace Nf governor.

(12) Customer bleed air

gasket, fuel nozzle gasket, and P3 filter gasket (PPC No. 56 Installed), deterioration or loose bolts.

(a) Inspect gaskets and bolts. 1. Replace defective parts. Tighten bolts.

(a) Determine torquemeter correction factors from logbook records.

1. Adjust indicated torque for torquemeter inaccuracy.

(13) Reduction gearbox torquemeter.

(b) Hover with good power section and note torque required. Repeat with suspect power section. If torque required is less, gearbox torquemeter error may be problem.

1. Replace defective gearbox.

28 (Cont)

(14) Undetermined power section performance deterioration.

(a) Accomplish a compressor wash on affected power section, then accomplish performance check.

1. Replace power section if per-formance has not recovered to within acceptable limits.


4-22


(1) Instrument. (a) Verify accuracy of system. 1. Replace faulty component.

(2) Pressure regulating

valve. (a) Use direct reading gage on

power section inlet line. 1. Accomplish oil

pressure check and adjustment.

(3) Oil cooler. (a) Check for restricted oil

passageway. 1. Replace defective

oil cooler.

29 High or Low Power Section Oil Premium At Normal Operating Temperatures

(4) Breather line. (a) Check for restriction or blockage.

1. Clear obstruction.


(2) Pressure regulating

valve. (a) Use direct reading gage on

reduction gearbox inlet line. 1. On aircraft with

T400 PPC No. 26 installed, accom-plish oil pressure check and adjust-ment. If T400 PPC No. 26 is not installed, replace reduction gearbox.

(3) Oil cooler. (a) Check for restricted oil

passageway. 1. Replace defective

oil cooler.

30 High or Low Reduction Gearbox Oil Pressure At Normal Operation Temperature

(4) Breather line. (a) Check for restriction or blockage.


(a) Fluctuating ITT, see Fluctuating Interturbine Temperature (item 16).

(b) Fluctuating Ng; see Compressor Stall (item 11).

1. Replace power turbine governor if defective.

2. Replace torque

control unit if defective.

31 Engine Parameters Fluctuating

(1) Automatic fuel system component malfunction.

(c) Fluctuating Nf, Q, Ng, ITT, Wf. Accomplish power turbine governor rigging. Isolate torque control unit from system. Isolate power turbine governor. Refer to Notes 1 through 7 for additional instructions.

3. Replace AFCU if problem persists.


4-23


(2) Power section deterioration.

(a) See Low Power/Torque (item 28).

(3) Dirty electrical harness connectors.

(a) Disconnect and inspect. 1. Clean and install.

31 (cont)

(4) Malfunctioning linear actuator.

(a) In flight fluctuating Nf and Nr.

1. Replace linear actuator.

(a) Check oil levels. (Remove reduction gearbox oil system filler cap to assure accurate reading.)

1. Service system to proper level.

(1) Oil system over-serviced.

(b) See High Oil Consumption (item 23).

32 Oil Dripping From Breather Lines (Power Section or Reduction Gearbox)

(2) Centrifugal breather face type carbon seal.

(a) Inspect seal for chipped, cocked or cracked condition.

1. Replace seal.

(1) Oil system over-serviced.

(a) Check oil level. 1. Service system to proper level.

33 Oil Leaking From Power Section Compressor Inlet

(2) Overboard breather line restricted.

(a) Check for blockage/ restriction in overboard breather line.

1. Clear blockage/ remove restriction. If none, replace power section.

34 When Power

Section or Reduction Gearbox Chip Detector Warning Light Illuminates

NOTE

Attention is drawn to the following points: (1) The power section oil systems are designed to run contamination free. Metal contamination implies particles or chips greater than 10 microns in size. Any chips greater than 10-micron size yet small enough to be swept about by oil must be deposited either on engine oil filter or on chip detectors. (2) Flushing the power section is normally considered as a procedure to be used when changing from one type of oil to another.


4-24


(a) Check electrical system and isolate problem area.

1. Clean appropriate chip detectors and inspect oil filter in the sys-tem. Run engine for 10 minutes at a convenient high power, without exceeding limits. Remove and inspect oil filter again. If no significant metallic pickup is found, engine is acceptable.

2. If significant

pick-up is found on reduction gearbox middle oil filter or chip detector on gearbox output section, replace reduction gearbox.

(1) Normal wear.

(b) Check chip detector within the system that has the problem.

3. If reduction gear-box or power section is re-placed due to metallic pick-up, flush oil cooler and all connecting lines.

1. Remove and

replace reduction gearbox and its affected power section.

34 (Cont)

(2) Excessive wear. (a) Remove all chip detectors and filters. If metallic pick-up consists of flakes or other particles not in the category of fuzz or fine slivers, excessive wear is indicated. 2. If excessive

metallic pick-up occurs on middle oil filters or chip detector on gearbox output section, replace reduction gearbox.


4-25

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action 34 (cont)

(2) (Cont) 3. If excessive metallic pick-up occurs on accessory gear-box chip detector or power section oil filter, replace power section and reduction gearbox. If metallic pick-up is found in the external line of the engine oil system or if particles are suspected of being present in the oil cooler, the oil cooler shall be flushed. If it is necessary to replace the power section because of metal chip damage, the oil cooler shall be flushed.

(1) Worn reduction

gearbox mount components.

(a) Inspect reduction gearbox mount bearings.


(2) Compressor bleed valve cycling.

(a) Isolate malfunctioning valve by checking with bubbler bottle.

1. Replace bleed valve.

(3) Internal damage to reduction gearbox.

(a) Check chip detectors and oil filters.

1. Replace gearbox.

(4) Tail rotor driveshaft. (a) Check proper installation. 1. Replace as required.

(5) Worn front engine

mount system.

(a) Inspect front mount system. 1. Replace defective components.

35 Vibration

(6) Internal damage to accessory gearbox.

(a) Check chip detector. 1. Replace power section.


4-26


(7) Power turbine. (a) Inspect power turbine blades.

1. Replace power section if broken blades are found.

(8) Compressor

damage.

(a) Inspect compressor. 1. Replace power section.

35 (Cont)

(9) Engine oil cooler blowers.

(a) Isolate oil cooler blower from power section. Run section at varying Nf.

1. Replace defective component.

(1) Compressor inlet blockage.

(a) Inspect inlet screen and ducts.



(a) Inspect bleed valve operation using bubbler bottle.

1. Replace bleed valve as required.

(3) Acceleration adjustment.

(a) Perform acceleration check. 1. Adjust AFCU as necessary.

(4) Dirty compressor. (a) Visually inspect. 1. Wash engine.

(5) Defective AFCU. 1. Replace AFCU.

36 Stall During Acceleration


(a) Inspect for damage. 1. Replace power section.

(1) Airframe linkage. (a) Inspect linkage. 1. Repair or adjust

as required.

(2) Blockage of pneumatic sense line from Nf governor. This can be accompanied by Nr overspeed.

(a) Debris, dirt or ice accumulation.

1. Remove blockage.

(3) Nf governor fails to limit power section power. This can be accompanied by Nr overspeed.

(a) Nf governor orifice blocked. 1. Remove and clean orifice.

(4) Nf governor. 1. Replace governor.

37 Overspeed (Nf)

NOTE

Simultaneous loss of Nf governor drive, Nf tach drive and blower drive usually indicates RGB idler gear failure.


4-27


(1) Maximum AFCU stop out of adjustment.

(a) Perform part power trim check.

1. Adjust maximum Ng Stop.

(2) Nf governor fails to limit power section power. This can be accompanied by Nr overspeed.

(a) Nf governor orifice blocked. 1. Remove and clean orifice.

(3) Loss of Ng governor drive.

(a) Check for worn coupling between pump and AFCU.


38 Overspeed (Ng)

(4) Defective AFCU.

1. Replace AFCU.

(1) Defective solenoid valve.

(a) Perform operational check. 1. Replace solenoid valve on MFCU.

(2) Airframe wiring. (a) Check airframe wiring. 1. Repair as necessary.

39 Inability To Switch From AFCU To MFCU

(3) Defective MFCU. 1. Replace MFCU.

(1) Fuel pump leakage. (a) Check fuel pump drain area. 1. Replace AFCU and pump.

40 Fuel Leakage From AFCU/Pump Drain

(2) Fuel leakage from AFCU pneumatic bleed.

(a) Check air bleed in bottom of AFCU.

1. Replace AFCU and pump.

(1) Airframe to power section rigging out of adjustment.

(a) Check airframe rigging. 1. Adjust rigging.


1. Clean orifice.

41 High Nf Speed

(3) Governor orifice blockage.

(a) Inspect orifice.

2. Replace governor.

(a) Refer to procedures for interconnect linkage adjustment.

1. Adjust inter-connect linkage.

(1) Interconnect linkage out of adjustment.

(b) Check-Manual-Automatic fuel control linkage.

1. Adjust linkage.

42 Excessive Ng Increase During Crossover From AFCU to MFCU

(2) Pg line leakage. (a) Check fittings and lines. 1. Tighten or replace as required.


4-28

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action 43 Fuel Filter

Caution Panel Illuminated

(1) Filter element clogged.

(a) Remove and inspect filter element.

1. Replace filter element. Perform operational check.

(1) Obstructed pump

line through flow switch and ejector pump.

(a) If fuel flow indicator showed fuel reaching engine, units of internal fuel line in underfloor cell.

1. Clean screen in pump outlet fitting, or replace flow switch or ejector pump or obstructed hoses.

(2) No electrical power

to pump. (a) With FUEL CONT switch

ON, check for sound of pump running. If no sound, check for electrical continuity.

1. Repair wiring or replace faulty units in circuit.

44 Fuel Boost Caution Panel Illuminated

(3) Defective pump. (a) If pump runs, but there is no indication of fuel flow to engine, pump has failed.

1. Replace pump.

45 Fuel Shutoff Valve Inoperative

(1) Valve faulty or lacking electrical power.

(a) Check for power at valve; if available, valve is faulty.

1. Repair circuit or replace valve.

46 Fuel Interconnect Valve Inoperative

(1) Valve faulty or lacking electrical power.

(a) Check for power at valve; if available, valve is faulty.

1. Repair circuit or replace valve.

(1) Faulty nozzle connection.

(a) Check connection. 1. Connect nozzle securely to fueling valve.

47 No Flow When Pressure Fueling

(2) Either test valve not fully closed and leaking internally.

(a) Feel each test valve line to detect flow. Verify by disconnecting lines from test valves, connecting hoses leading into a container, and observing for flow from a leaking valve.

1. Replace test valve, or fueling valve.


4-29


(3) Reversed check valves in shutoff valve sensing lines.

(a) Visually inspect direction of flow arrows on check valves cell access door.

1. Install check valves with flow arrows toward door.

(4) Shutoff valve

malfunction. (a) Disconnect shutoff valve

sensing lines from check valves on center cell door, place ends on a container. Start fueling, if either line fails to flow, valve is faulty.

1. Replace shutoff valves.

47 (Cont)

(5) Pilot valve malfunction.

(a) Eliminate other possible cause.

1. Replace pilot valve.

(1) Test valve mal-function or line obstructed.

(a) Disconnect test valve lines, place ends in a container, observe for flow and for stoppage of flow when test valve is actuated.

1. Replace defective test valve, or fueling valve assembly, or obstructed line.

(2) Shutoff valve malfunction.

(a) Disconnect shutoff valve sensing lines at center cell door. In turn, cap each line and check that shutoff valve stops fueling flow.

1. Replace shutoff valve.

48 Fueling Flow Not Stopped By Test Valve Use

(3) Pilot valve malfunction.

(a) Eliminate other possible causes.

1. Replace pilot valve.

(1) Pump discharge hose coupling not seated.

(a) Visual and manual check of quick disconnect coupling.

1. Connect properly or replace coupling.

(2) Check valve blocked.

(a) Remove and inspect valve. 1. Clean or replace valve.

49 No Fuel Transfer From One Aux. Tank

(3) Pump or electrical circuit faulty.

(a) Electrical check of pump circuit.

1. Repair wiring or replace defective pump or switch.

50 No Fuel

Transfer From Either Aux. Tank

(1) Transfer relay or lower float switch or circuit faulty.

(a) Electrical check of relay and circuit.

1. Repair wiring or replace defective relay or float switch.


4-30 Change 5

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action 51 Fuel

Overflows Main Tank Vents During Transfer

(1) Upper float switch not actuating transfer relay.

(a) Electrical check of relay circuit.

1. Repair wiring or replace defective float switch or transfer relay.

(1) Vent valve stuck closed or vent line blocked.

(a) Check vent line connection from lower end to fittings on tank to locate obstructed part.

1. Clear obstructed line or replace faulty vent fitting.

52 Auxiliary Tank Collapsing During Transfer

(2) Low-level float switch or caution panel or circuit faulty.

(a) Electrical check of caution panel-float switch circuit.

1. Repair wiring or replace defective component.

(1) Surge dampener malfunction.

(a) Note level of rumble. 1. Low rumble associated with fuel system resonance is acceptable. If rumble exists above 70 percent, refer to high power rumble.

53 Low Speed Rumble

(2) Compressor bleed valve malfunction.

(a) Check for proper operation.

1. Replace valve.

(1) Surge dampener malfunction.

1. Replace surge dampener.

54 High Power Rumble

(2) FOD or erosion on compressor.

(a) Inspect 1st stage compressor blades.


(1) Incorrect adjustment.

1. Adjust torque control.

(2) Air in bellows. 1. Bleed torque control bellows.

55 Fails To Limit Torque

(3) Defective torque control.

1. Replace torque control.

CAUTION

Failure to secure plugs in PG air lines properly could result in an air leak. PG air leaks may

induce a hung or slow start. If this occurs, refer to items 4 and 5 of this Troubleshooting Guide. Do not perform an automatic to manual fuel mode crossover until the starting discrepancy is resolved. Switching to manual mode may result in a spike in fuel flow that will increase gas path temperatures to the point of power section failure.


Change 5 4-30A/(4-30B Blank)

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action NOTES

1. To determine if AFCU is faulty, disconnect Pg line (2, figure 4-10) from AFCU. Install a No.4

plug onto elbow (21) at the AFCU. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is repeated, AFCU is suspect and shall be replaced. If discrepant performance is not repeated, AFCU can no longer be considered a potential source of discrepancy and should not be replaced. If discrepant performance is not repeated, reconnect Pg line to AFCU and continue troubleshooting.


4-31

TABLE 4-1. TROUBLESHOOTING - (Continued) Item Trouble Probable Cause Troubleshooting Corrective Action 2. Troubleshoot for a Pg leak by disconnecting Pg line (3, figure 4-25) which extends from

AFCU to front fireseal from heated Pg tube (23) at front fireseal. Install a No. 4 plug into Pg line (3) extending forward to AFCU. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is repeated, the Pg line which extends forward to AFCU is suspect. The torque at each ferrule should be checked. If the discrepant performance continues, the subject Pg line shall be replaced. If discrepant performance is not completed, the subject Pg line cannot be considered a potential source of the Pg leak and should not be replaced. Reconnect the Pg line and continue troubleshooting as follows: Repeat this procedure at the rear fireseal (bulkhead) (38) and at four-way fitting (41) on the RGB. If discrepant performance is repeated, the Pg line which is plugged and which extends forward to the next ferrule location is suspect and shall be replaced.

3. To determine if the power turbine governor is faulty, disconnect Pg line (1, figure 4-16)

from power turbine governor. Install a No. 4 plug into end of Pg line to seal off Pg system before it enters the power turbine governor end thereby isolate power turbine governor from Pg system. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is not repeated, power turbine governor is suspect and shall be replaced. If discrepant performance is repeated, power turbine governor can no longer be considered a potential source of discrepancy and should not be replaced. If discrepant performance is repeated, reconnect Pg line to power turbine governor and continue troubleshooting.

4. Disconnect power turbine governor Pg line at four-way fitting. Install a cap onto four-way

fitting. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is not repeated, the Pg line which has been disconnected is suspect and shall be replaced. If discrepant performance is repeated, reconnect the Pg line and continue troubleshooting.

5. To determine if torque control unit is faulty, disconnect Pg line (7, figure 4-17) from torque

control unit. Install a No. 4 plug into the end of Pg line to seal off Pg system before it enters torque control unit and thereby isolate torque control unit from Pg system. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is not repeated, the torque control unit is suspect and shall be replaced. If discrepant performance is repeated, the torque control unit can no longer be considered a potential source of discrepancy and should not be replaced. If discrepant performance is repeated, reconnect Pg line to torque control unit and continue troubleshooting.

6. Disconnect the torque control unit Pg line at the four-way fitting. Install a plug onto four-

way fitting. Operate power section as necessary to repeat the discrepant performance. If discrepant performance is not repeated, the Pg line which has been disconnected is suspect and shall be replaced. If discrepant performance is repeated, reconnect Pg line and continue troubleshooting.

7. To determine if the air accumulator is faulty, disconnect air accumulator from the four-way

fitting (41, figure 4-25). Install a No. 4 cap onto the end of four-way fitting to seal off Pg system before it enters the air accumulator and thereby isolate the air accumulator from Pg system. Operate power section as necessary to repeat discrepant performance. If discrepant performance is not repeated, the air accumulator is suspect and shall be replaced. If discrepant performance is repeated, the air accumulator can no longer be considered a potential source of discrepancy and should not be replaced. If discrepant performance is repeated, reconnect four-way fitting to air accumulator.


4-32 Change 4

4-6. POWER PLANT PACKAGE COMPONENT REPLACEMENT.

NOTE

Table 4-2 provides a listing of com-ponents, reference paragraphs for re-placement instructions and functional check to be performed after replacement.

4-7. REDUCTION GEARBOX OIL FILTERS AND OIL PRESSURE TRANSMITTER. Three oil filters are located on rear side of the reduction gearbox, one for each power section oil system and one for the gearbox oil system. The oil pressure trans-mitter is located in top of reduction gearbox. 4-8. REMOVAL. (Figure 4-1.) a. Remove oil filters as follows: 1. Place suitable container under filter cover (1). Remove three nuts (2) and washers (3). 2. Remove cover (1) and element assembly (5) and packings (4 and 7). 3. Remove retaining ring (6) and filter element (5) from cover.

NOTE

If minor dents do not increase mesh size, do not replace filter. If metallic flakes or particles are found, check with a magnet to determine if chips are magnetic. Non-magnetic silver colored flakes/particles and non-magnetic silver colored flakes which have copper coloring on one side originate from silver plating on the bearing cages. Loss of silver plating is normal during operation of gearbox, does NOT degrade RGB and does NOT warrant removal of RGB. Magnetic flakes and particles indicate impending failure in the gearbox. Troubleshoot magnetic flakes and particles in accordance with NA 02B-20AA-6-1, WP 050 00.

4. Inspect filter element for metal particles or other contamination.

5. Inspect filter element for broken or dented wires; if any found, install replacement element. b. Remove oil pressure transmitter as follows: 1. Disconnect electrical connector (13) and remove gearbox oil pressure transmitter (10) and discard packing (9). 2. Remove restrictor (8). 3. Remove plug (12) from transmitter and retain plug for installation.

NOTE

Plug (12) shall be installed to alleviate oil pressure fluctuation.

4-9. INSTALLATION. (Figure 4-1.) a. Install oil filters as follows: 1. Install new packing (7) in internal bore of filter element (5). 2. Insert element into cover (1) with lugs outward, and secure with retaining ring (6). 3. Install new packing (4) on cover. 4. Install filter cover over studs on moun-ting face and secure with three washers (3) and nuts (2). Torque nuts 35 to 40 inch-pounds. (QA) b. Install oil pressure transmitter as follows:

Lubricating Oil 1 1. Install new packing (11) lubricated with oil, MIL-PRF-23699, on plug (12). 2. Install plug (12) in transmitter. (QA) 3. Install restrictor (8) until it bottoms out in transmitter (10). Make one segment stake to the threads of transmitter to secure restrictor.


Change 4 4-33

TABLE 4-2. COMPONENT REPLACEMENT CHECKS Paragraph No. Component Functional Check 4-7 Oil Filter and Oil Pressure

Transmitter

Visual inspection.

4-10 Centrifugal Breather Carbon Seal

Visual inspection.

4-13/4-15 Output Shaft Carbon Seal

Visual inspection.

4-24 Oil-to-Fuel Heater Dry Motoring Run, followed by inspection for leakage. (Paragraph 4-247.)

4-27 Fuel Pump Filter Visual Inspection.

4-30 Automatic Fuel Control Unit Maximum and Idle Gas Generator Speeds Adjustment. (Paragraph 4-249.)

4-33 Manual Fuel Control Unit Maximum and Idle Gas Generator Speeds Adjustment (Paragraph 4-247.)

4-36 Fuel Pump Wet Motoring Run, followed by inspection for leakage. (Paragraph 4-261.)

4-54 Flow Divider Power Section Start (See Flight Manual.)

4-64 Power Turbine Governor Power Turbine Governors Matching. (Paragraph 4-259.)

4-68 Torque Control Unit Torque Control Adjustment. (Paragraph 4-258.)

4-125 ITT Limiter ITT Trim Check and Adjustment. (Paragraph 4-250.)


4-34

Figure 4-1. Oil Filter Element (Typical) and Oil Pressure Transmitter


Change 5 4-35

Lubricating Oil 1 4. Install new packing (9, figure 4-1) lubricated with oil, MIL-PRF-23699, on transmitter (10) and install transmitter to reduction gearbox and lockwire. (QA) 5. Connect electrical connector (13) to transmitter (10) and lockwire. (QA) 4-10. CENTRIFUGAL BREATHER FACE TYPE CARBON SEAL. 4-11. REMOVAL. (Figure 4-2.) a. Remove induction baffle. Refer to para-graph 4-156. b. Remove seal carrier retaining ring (1).

CAUTION

To avoid damage to carbon face seal, assure that rod of puller is not screwed into back of seal carrier.

c. Remove seal carrier (2) using puller (CPWA 30046-62) and hand pressure. d. Remove face seal (2, figure 4-3) from carrier using puller (PWC 32810), wrench and 1/4 (0.25) inch allen type key. 4-12. INSTALLATION. (Figure 4-2.)

Lubricating Oil 1

CAUTION

Do not touch faces of carbon seals with bare hands, as damage to seal may result.

a. Lubricate carbon seal (3) with engine oil, MIL-PRF-23699, and assure carbon face moves freely in and out against spring.

WARNING

Handling of hot parts with bare hands may cause reddening and blistering of skin, or third degree burns. If skin is burned, immerse contacted area in cold water for 10 minutes. If pain or blistering persists, immediately get medical attention. When handling hot parts, wear approved gloves.

b. Heat carrier (2) in clean engine oil, heated to 250°F (121°C). When carrier has reached the same temperature as oil, remove and install face seal (3) in carrier using drift (CPWA 30675) and arbor press. Assure correct seating of seal in carrier using 0.002 inch feeler gage. (QA) c. Moisten two new packings (4) with engine oil, MIL-PRF-23699, and install on seal carrier. d. Press seal carrier into accessory gearbox using drift (CPWA 30075); assure proper align-ment. (QA) e. Install seal carrier retaining ring (1). f. Install induction baffle. Refer to paragraph 4-156. 4-13. OUTPUT SHAFT FACE-TYPE SEAL AND RUNNER – PRIOR TO PPC NO. 8 AND RGB NO. 3168. 4-14. REPLACEMENT.

CAUTION

Do not touch faces of carbon seals with bare hands, as damage to seal may result.

a. Remove driveshaft/adapter. Refer to NAVAIR 01-110HCE-2-4. Remove four bolts (1, figure 4-4) and washers (2). Withdraw seal carrier (3) using puller (CPWA 30748) (9).


4-36

Figure 4-2. Centrifugal Breather Face-Type Carbon Seal


Change 5 4-37

Figure 4-3. Face Seal Removal From Carrier b. Remove face-type seal (5, figure 4-4) from carrier (3) using pusher (CPWA 30810).

NOTE

Do not try to separate carbon seal and retainer.

Replace runner (8) whenever carbon seal is replaced.

c. Unlock key-washer (7) using a suitable punch. d. Install wrench (CPWA 30857) (1, figure 4-5) on output shaft, align dogs (6) of socket assembly (2) with slots (7) of plain nut (5), and install knurled nut (4), assuring that dogs engage with slots.

e. Hold spline assembly (3) steady, and apply pressure in direction shown to socket assembly (2) until plain nut (5) is loose. f. Remove wrench (1), plain nut (6, figure 4-4), key-washer (7), runner (8) and packing (10) from output shaft.

Lubricating Oil 1 g. Lubricate new packing (10) with engine oil, MIL-PRF-23699, and install packing, new runner (8), new key-washer (7) and plain nut (6) on output shaft. Torque nut 735 to 920 inch-pounds. Do not stake key-washer at this time. (QA)


4-38 Change 2

Figure 4-4. Output Shaft Face Seal (Pre-PPC No. 8)


Change 5 4-39

Figure 4-5. Removing Output Shaft Seal Nut h. Using a dial indicator, check that runner is square within 0.0004 inch total indicator reading. If outside limit, loosen nut and rotate through 90 degrees and recheck. If out of limit, replace runner and repeat check. i. When runner is within limits, remove dial indicator. Stake key-washer (7, figure 4-4) using a punch.

Lubricating Oil 1

j. Lubricate carbon seal (5) with engine oil, MIL-PRF-23699, and assure that seal moves in and out freely against spring. k. Install combined seal and retainer into seal carrier (3), using pusher (CPWA 30810) or drift (CPWA 30671). I. Install new packing (4) on seal carrier (3); lubricate with engine oil, MIL-PRF-23699. m. Install seal carrier assembly over output shaft and secure to gearbox with four washers (2) and bolts (1). Torque bolts 32 to 36 inch-pounds and Iockwire in pairs. (QA) n. Install driveshaft/adapter. Refer to NAVAIR 01-110HCE-2-4.


4-40 Change 4

4-15. OUTPUT SHAFT FACE-TYPE SEAL AND RUNNER – INCORPORATING PPC NO. 8 AND RGB NO. 3168. 4-16. REPLACEMENT.

CAUTION

Do not touch faces of carbon seal with bare hands, as damage to seal may result.

a. Remove driveshaft/adapter. Refer to NAVAIR 01-110HCE-2-4. Remove four bolts (1, figure 4-6) and washers (2), securing cover (3). b. Remove cover (3), gasket (12) and seal carrier (4). c. Remove face seal (6) from carrier (4) using pusher (CPWA 30810) or drift (CPWA 30661) and support (CPWA 30670).

NOTE

Do not try to separate carbon seal and retainer.

Replace runner (9) whenever seal is replaced.

d. Unlock key-washer (8) using a punch. e. Install wrench (CPWA 30857) on output shaft, align dogs (6, figure 4-5) of socket assembly (2) with slots (7) of plain nut (5) and install knurled nut (4), assuring that dogs engage with slots. f. Hold spline assembly (3) steady and apply pressure, in direction shown, to socket assembly (2) until plain nut (5) is loose. g. Remove wrench (1), plain nut (5), key-washer (8, figure 4-6), runner (9) and packing (10) from output shaft.

Lubricating Oil 1 h. Lubricate new packing (10) with engine oil, MIL-PRF-23699, and install packing (10), new runner (9), key-washer (8) and plain nut (7) on output shaft. Torque nut 2300 to 2400 inch-pounds, loosen to zero and retorque to 1200 to 1300 inch-pounds. Do not stake key-washer at this stage. (QA)

NOTE

Following check is not required when utilizing runner assembly 3021665.

i. Using a dial indicator, check that runner is square within 0.0005 inch total indicator reading. If outside limits, loosen nut and rotate runner through 90 degrees and recheck, rotate through a further 90 degrees if required and recheck. If still outside limits, remove runner and replace with a selected item. Repeat runout check. j. When runner is within limits, remove dial indicator. Stake key-washer (8) using a punch. k. Lubricate face seal (6) with engine oil, MIL-PRF-23699, and assure carbon face moves freely in and out against spring. I. Install face seal (6) into seal carrier (4) using pusher (CPWA 30810) or drift (CPWA 30671) and support (CPWA 30670). m. Lubricate new packing (5) with engine oil, MIL-PRF-23699, and install on seal carrier (4). n. Install seal carrier assembly (4) over output shaft, install new gasket (12) and install cover (3) with drainage point at 6 o'clock position. Secure with four washers (2) and bolts (1). Torque bolts 32 to 36 inch-pounds and Iockwire in pairs. (QA) o. Install driveshaft/adapter. Refer to NAVAIR 01-110HCE-2-4.


Change 2 4-41

Figure 4-6. Output Shaft Face Seal (Post PPC No. 8)


4-42 Change 4

4-17. ACCESSORY DRIVE SEAL. 4-18. REPLACEMENT OF FUEL PUMP DRIVE SEAL. (Figure 47, Detail A.) a. Remove fuel pump with automatic (AFCU) and manual fuel control unit (MFCU) as one assembly. Refer to paragraph 4-30. b. Remove retaining ring (4) from fuel pump drive boss. c. Withdraw seal carrier (3) from boss using puller (CPWA 30046-62) (5, figure 4-2) and two conventional wrenches (6 and 7). d. Remove seal (2, figure 4-7) from carrier (3) by pressing gently with fingers.

Lubricating Oil 1 e. Moisten new silicone element seal (2) with engine oil, MIL-PRF-23699, and gently press into seal carrier (3) from pressure side. f. Lubricate new packing (1) with engine oil, MIL-PRF-23699, and install on seal carrier (3). g. Install carrier (3) in fuel pump drive boss using drift (CPWA 30075). Assure that lips of seal are not damaged during assembly. h. Install retaining ring (4). i. Install fuel pump with AFCU and MFCU as a complete unit. Refer to paragraph 4-30. 4-19. REPLACEMENT OF STARTER-GENERA-TOR DRIVE SEAL. (Figure 4-7, Detail A.) a. Remove starter-generator. Refer to para-graph 4-183. b. Remove retaining ring (4) from accessory gearbox.

c. Withdraw seal carrier (3) from gearbox, using puller (CPWA 30046-64) (5, figure 4-2) and two conventional wrenches (6 and 7). d. Remove seal (2, figure 4-7) from carrier (3) by pressing out gently with fingers.

Lubricating Oil 1 e. Moisten new silicone element seal (2) with engine oil, MIL-PRF-23699, and gently press into seal carrier (3) from pressure side. f. Lubricate new packing (1) with engine oil, MIL-PRF-23699, and install on seal carrier (3). g. Install carrier in accessory gearbox boss, using drift (CPWA 30075). Assure that lips of seal are not damaged during assembly. h. Install retaining ring (4). i. Install starter-generator. Refer to para-graph 4-183. 4-20. REPLACEMENT OF Ng TACHOMETER GENERATOR DRIVE SEAL. (Figure 4-7, Detail B.) a. Remove Ng tachometer-generator from accessory gearbox. Refer to NAVAIR 01-110HCE-2-10. b. Withdraw seal carrier (3) from accessory gearbox, using puller (CPWA 30046-61). c. Remove seal (2) from carrier (3) by pressing out gently with fingers.

Lubricating Oil 1 d. Moisten new silicone element seal (2) with engine oil, MIL-PRF-23699, and gently press into seal carrier (3) from pressure side.


Change 5 4-43

Figure 4-7. Replacement of Accessory Drive Seals (Typical)

Lubricating Oil 1 e. Lubricate new packing (1, figure 4-7) with engine oil, MIL-PRF-23699, and install on seal carrier (3). f. Install carrier (3) in accessory gearbox boss, using drift (CPWA 30075). Assure that lips of seal are not damaged during assembly.

g. Install Ng tachometer-generator. Refer to NAVAIR 01-110HCE-2-10. 4-21. REPLACEMENT OF POWER TURBINE GOVERNOR DRIVE SEAL. (Figure 4-7, Detail B.) a. Remove power turbine governor. Refer to paragraph 4-64. b. Withdraw seal carrier (3) from reduction gearbox using puller (CPWA 30046-61) (5, figure 4-2) and two conventional wrenches (6 and 7). c. Remove seal (2, figure 4-7) from carrier (3) by pressing out gently with fingers.


4-44 Change 5

Lubricating Oil 1 d. Moisten new silicone element seal (2, fig-ure 4-7) with engine oil, MIL-PRF-23699, and gently press into seal carrier (3) from pressure side. e. Lubricate new packing (1) with engine oil, MIL-PRF-23699, and install on seal carrier (3). f. Install carrier (3) in reduction gearbox boss, using drift (CPWA 30075). Assure that lips of seal are not damaged during assembly. g. Install power turbine governor. Refer to paragraph 4-64. 4-22. REPLACEMENT OF Nf TACHOMETER GENERATOR DRIVE SEAL. (Figure 4-7, Detail B.) a. Remove Nf tachometer-generator. Refer to NAVAIR 01-110HCE-2-10. b. Withdraw seal carrier (3) from reduction gearbox using puller (CPWA 30046-61) (5, figure 4-2) and two wrenches (6 and 7). c. Remove seal (2, figure 4-7) from carrier (3) by pressing gently with fingers.

Lubricating Oil 1 d. Moisten new silicone element seal (2) with engine oil, MIL-PRF-23699, and gently press into seal carrier (3) from pressure side. e. Lubricate new packing (1) with engine oil, MIL-PRF-23699, and install on seal carrier (3). f. Install carrier (3) in reduction gearbox boss, using drift (CPWA 30075). Assure that lips of seal are not damaged during assembly. g. Install Nf tachometer-generator. Refer to NAVAIR 01-110HCE-2-10.

4-23. REPLACEMENT OF BLOWER DRIVE –DRIVE SEAL. (Figure 4-8.) a. Remove oil cooler blower from reduction gearbox. Refer to paragraph 4-172. b. Remove seal carrier retaining ring (1). c. Withdraw seal carrier (2) from gearbox using puller (CPWA 30646). d. Remove oil seal (4) from carrier (2) by pressing out with fingers.

Lubricating Oil 1 e. Lubricate new oil seal (4) with engine oil, MIL-PRF-23699, and gently press into seal carrier (2) from pressure side. f. Lubricate new packing (3) with engine oil, MIL-PRF-23699, and install on seal carrier (2). g. Press seal carrier (2) into blower drive boss. Assure lips of seal (4) are not damaged during assembly operation. h. Secure carrier (2) with retaining ring (1). i. Install oil cooler blower. Refer to para-graph 4-172. 4-24. OIL-TO-FUEL HEATERS. An oil-to-fuel heater is located on the front of each accessory gearbox. Function is to prevent ice formation in the fuel. 4-25. REMOVAL. (Figure 4-9.)

Aviation Turbine Fuel 2 a. Disconnect tube fuel inlet connection (1) and cap tube end.


Change 4 4-45

b. Remove two bolts (4, figure 4-9) from elbow connection (6) on fuel pump inlet (23). Remove elbow and transfer tube (24). c. Remove three bolts (28) and washers (27) securing oil-to-fuel heater (2) to accessory gearbox. d. Remove oil-to-fuel heater and two transfer tubes (26) protruding from mounting face on accessory gearbox. 4-26. INSTALLATION. (Figure 4-9.)

Lubricating Oil 1

NOTE

Assure new oil-to-fuel heater complies with PPC No. 61.

a. Moisten four packings (3) with engine oil, MIL-PRF-23699, and install on two oil transfer tubes (26). b. Install two oil transfer tubes in orifices on oil-to-fuel heater mounting face on accessory gearbox. c. Install oil-to-fuel heater (2) over transfer tubes, aligning bolt holes and taking care not to damage packings. d. Secure oil-to-fuel heater to accessory gear-box with three bolts (28) and washers (27). Torque bolts 32 to 36 inch-pounds and Iockwire. (QA)

Aviation Turbine Fuel 2 e. Moisten two packings (25) with fuel and install on fuel transfer tube (24). Insert fuel transfer tube into fuel outlet port on oil-to-fuel heater taking care not to damage packing.

Figure 4-8. Accessory Drive Seal – Blower Drive

f. Moisten packing (7) with fuel and install in groove on mating face (23) of elbow connector (6) to fuel pump. Install elbow connector over fuel transfer tube taking care not to damage packing and secure elbow connector to fuel pump (21) with two washers (5) and bolts (4). Torque bolts 25 to 35 inch-pounds. Secure with Iockwire. (QA) g. Connect fuel inlet tube to oil-to-fuel heater connection (1). Torque fitting 450 to 500 inch-pounds. Secure with lockwire. (QA) h. Check for leaks during ground run. Allow oil temperature to reach normal operating temperature.


4-46

Figure 4-9. Oil to Fuel Heater, Fuel Pump and Filter


Change 4 4-47

i. Shut down power section.

CAUTION

Carefully touch engine driven fuel pump filter bowl to verify if bowl is comfortable to touch. A malfunctioning thermal element could allow fuel temperature at this point to rise beyond 170°F.

j. Verify immediately that the engine driven fuel pump filter bowl is comfortable to touch, 70° to 90°F.

NOTE

This check shall be performed within 5 minutes of power section shutdown to be valid.

k. If fuel pump filter bowl is not comfortable to touch, the oil-to-fuel heater should be returned to depot for repair. 4-27. FUEL PUMP FILTERS. A filter is located on left side of each fuel pump, on front of each accessory gearbox.

NOTE

There is no periodic inspection require-ment for fuel pump filters. Inspect during troubleshooting or when contamination is suspected.

4-28. REMOVAL. (Figure 4-9.)

Aviation Turbine Fuel 2 a. Remove drain plug (18) and allow residual fuel to drain from filter cover (20).

b. Remove two bolts (17) end washers (16) securing fuel filter cover to fuel pump (21). Withdraw fuel filter cover and element assembly. c. Withdraw filter element. 4-29. INSTALLATION. (Figure 4-9.)

Calibration Fluid 3 a. Moisten two new packings (15) with calibration fluid, MIL-PRF-7024, Type II, or clean JP 4/5 fuel, install on internal boss of fuel filter cover (20). Insert new filter element (13) into cover. b. Moisten new packing (12) with calibration fluid, MIL-PRF-7024, Type II or clean JP 4/5 fuel, install on filter seating location within fuel pump (21). c. Moisten new packing (14) with calibration fluid, MIL-PRF-7024, Type II, or clean JP 4/5 fuel, install on filter cover. Install cover and element assembly on fuel pump. d. Secure cover with two washers (16) and bolts (17). Torque bolts 100 to 115 inch-pounds, and secure with lockwire. (QA) e. Moisten new packing (19) with calibration fluid, MIL-PRF-7024, Type II, or clean JP 4/5 fuel, install on drain plug (18). Insert plug into filter cover. Torque plug 40 to 65 inch-pounds and secure with lockwire. (QA) 4-30. AUTOMATIC FUEL CONTROL UNITS. An automatic fuel control unit (AFCU) is located on front of each accessory gearbox. Function is to regulate fuel flow in response to demand end performance changes, in fuel system automatic mode.


4-48 Change 4

4-31. REMOVAL.

Aviation Turbine Fuel 2

NOTE

It is advisable to remove manual fuel control unit (MFCU), automatic fuel control unit (AFCU) and fuel pump as one unit, before disassembly into separate units.

a. Disconnect P3 tube (3, figure 4-10) from AFCU. b. Disconnect P3 tube (8) from AFCU. c. Disconnect P3 tube (2) from AFCU. d. Disconnect power lever control system linkage from manual fuel control unit arm (18, figure 4-11). e. Disconnect electrical connector (10) from solenoid. f. Disconnect fuel outlet tube (13) from MFCU. g. Loosen bolts (28, figure 4-9) if required, sufficiently to give adequate clearance between the oil-to-fuel heater (2) and assembled fuel control unit during removal. h. Remove two bolts (4) and washers (5) securing inlet elbow (6) to fuel pump (21) and remove elbow (6) and transfer tube (24). i. Disconnect cavity drain line (22) from fuel pump (21). j. Remove three nuts (8) and washers (9) securing fuel pump (21) on mounting studs (10). k. Carefully withdraw complete unit (MFCU, AFCU and fuel pump) from mounting studs (10).

l. Remove two bolts (15, figure 4-11) securing tube (17) to MFCU. m. Remove two bolts (15) securing tube (16) to AFCU. n. Remove two bolts (15, figure 4-10) and locking plate (14), and detach tube (16) from AFCU. o. Remove two bolts (9) and locking plate (10), and detach tube (12) from AFCU. Retain filter assembly with AFCU.

CAUTION

Do not attempt to remove lever control arm (19) or its retaining nut and cotter pin.

p. Remove cotter pin (4) from lever arm pin (18). Withdraw pin and disconnect inter-connecting rod (5) from lever arm (19) of AFCU. q. Remove four nuts (1) and washers, and withdraw AFCU from mounting studs on fuel pump. On fuel pumps, without integral shaft coupling, keep shaft coupling (6) with power section. r. If unit is to be replaced by a new AFCU, loosen nut (20) and remove elbow (21); retain for replacement item. s. Retain filler and valve seat with plug. Secure with shipping cover, washers and screws. Torque screws 8 to 12 inch-pounds. (QA)

CAUTION

Automatic fuel control units with different part numbers are not interchangeable. Prior to installation, verify the correct part number for the type model series (TMS) of the subject power section (PS) per NA 02B-20AA-4.

4-32. INSTALLATION. a. If unit is a replacement item, install nut (20, figure 4-10) on elbow (21). Install a new backup ring (23) and packing (22) on elbow (21) and install in AFCU.


4-49

Figure 4-10. Automatic Fuel Control


4-50

Figure 4-11. Manual Fuel Control Unit


Change 4 4-51

WARNING

Engine will run uncontrollably if shaft coupling is not installed.

Lubricating Oil 1 b. Lubricate packings with engine oil, MIL-PRF-23699, prior to installation. c. On fuel pumps without integral shaft coupling, install shaft coupling (6, figure 4-10) in splined drive of fuel pump. Install packing (7) on mounting face of fuel pump. d. Install new packing (13) on tube (12), insert in AFCU and secure with plate (10) and two bolts (9). Torque bolts 25 to 35 inch-pounds and Iockwire together. (QA)

NOTE

Assure filter assembly is installed in AFCU prior to securing tube (12).

Use only new self-locking nuts during installation. Reusing old nuts may loosen component and result in flameout.

e. Install AFCU over mounting studs on fuel pump, assuring that splines of coupling (6) align with splines of AFCU and that packing (7) is in place. Secure unit with four nuts (1) and washers. Torque nuts 75 to 85 inch-pounds. (QA) f. Connect rod (5) with lever arm (19) with pin (18) and secure with cotter pin (4). g. Install new packing (17) on tube (16). Insert tube in AFCU and secure with plate (14) and two bolts (15). Torque bolts 25 to 35 inch-pounds and Iockwire together. (QA) h. Install new packing (14, figure 4-11) on mounting face of tube (17) and secure to MFCU with two bolts (15). Torque bolts 25 to 35 inch-pounds and Iockwire together. (QA) i. Install new packing (14) on mounting face of tube (16) and secure to MFCU with two bolts

(15). Torque bolts 25 to 35 inch-pounds and Iockwire together. (QA)

NOTE


j. Install new gasket (11, figure 4-9) over mounting studs (10) on accessory gearbox. Install assembled unit (MFCU, AFCU and pump) over studs and secure with three washers (9) and nuts (8). Torque nuts 75 to 85 inch-pounds. (QA) k. Connect drain line (22) to fuel pump. Torque connection 40 to 65 inch-pounds and Iockwire. (QA) I. If bolts (28) have been loosened, torque 32 to 36 inch-pounds and Iockwire. (QA) m. Install two packings (25) on transfer tube (24) and insert one end of tube in oil-to-fuel heater (2). n. Install packing (7) on inlet port face (23) of fuel pump. Install inlet elbow (6) over transfer tube (24) and port face (23). Secure with two washers (5) and bolts (4). Torque bolts 25 to 35 inch-pounds and Iockwire. (QA) o. Connect Pg tube (2, figure 4-10) to AFCU. Torque connection 90 to 100 inch-pounds. Torque nut (20) 40 to 65 inch-pounds and Iockwire connection and nut. (QA) p. Connect P3 tubes (3 and 8). Torque connections 90 to 100 inch-pounds and Iockwire. (QA) q. Connect electrical connector (10, figure 4-11) to solenoid. Install fingertight and Iockwire. (QA) r. Perform preliminary automatic to manual fuel control rigging (paragraph 4-243). s. Connect power lever control linkage to shaft (18) on MFCU and carry out rigging instructions in accordance with Rigging - Power Lever Controls.


4-52 Change 4

Aviation Turbine Fuel 2 t. Disconnect fuel inlet at flow divider and perform a wet motoring run for depreservation. Carry out adjustments and functional checks. Disconnect fuel flow divider inlet line and perform wet motoring run for depreserving a new replacement fuel control. 4-33. MANUAL FUEL CONTROL UNITS. A manual fuel control unit is located on front of each accessory gearbox. Function is to regulate fuel flow in response to pilot demand in fuel system manual mode. 4-34. REMOVAL.

NOTE

It is advisable to remove the manual fuel control unit (MFCU), automatic fuel control unit (AFCU) and fuel pump as one unit before disassembling into separate units.

a. Remove MFCU, AFCU and fuel pump as a complete assembly. b. Remove two bolts securing metered fuel tube. c. Remove two bolts securing unmetered fuel tube. d. Disconnect interconnect linkage. e. Remove three nuts (12, figure 4-11) and washers (11) and withdraw MFCU from mounting studs on fuel pump. f. If unit is to be replaced by a new MFCU, remove nipple (19), nut (1), spacer (2), pin (3), spacer (5), spring (7) and rod (6). Retain for replacement item.

4-35. INSTALLATION. a. If unit is a replacement item, install new packing (24, figure 4-11) on nipple (19) and insert nipple in MFCU. Torque 65 to 75 inch-pounds. (QA) b. Install spring (7) and spacer (5) on rod (6). Insert pin (3) through MFCU interconnecting arm (4) and insert rod (6) through pin.

Retaining Compound 4

CAUTION

During installation, check that torque required to turn self-locking adjusting nut is greater than 1.5 inch-pounds or less, remove existing nut and replace with a new nut of the same type.

c. Install spacer (2) on rod (6) protruding through pin (3) and secure with nut (1). Secure the nut in its final adjusted position with retaining compound, MIL-S-22473 (ASTM D5363), Grade A. d. Install two new packings (8) on mounting face transfer ports (9).

NOTE


e. Install MFCU over three mounting studs on fuel pump and secure with three washers (11) and nuts (12). Torque nuts 75 to 85 inch-pounds. (QA) f. Connect unmetered fuel tube. g. Connect metered fuel tube. h. Connect interconnect linkage.


Change 4 4-53

i. Install AFCU, MFCU and fuel pump as one unit.

Aviation Turbine Fuel 2 j. Perform preliminary automatic to manual fuel control rigging (paragraph 4-243). k. Disconnect fuel inlet at flow divider and perform a wet motoring run for depreservation. Carry out adjustments and functional checks. Disconnect fuel flow divider inlet line and perform wet motoring run for depreserving a new replacement fuel control. 4-36. FUEL PUMPS. A fuel pump is located on front of each accessory gearbox, between fuel control units and gearbox cover. Function is to deliver pressure fuel to control units. 4-37. REMOVAL.

NOTE

It is advisable to remove the manual fuel control unit (MFCU), automatic fuel control unit (AFCU) and fuel pump as one assembly, before disassembling into separate units.

a. Remove MFCU, AFCU and fuel pump from accessory gearbox and AFCU from fuel pump. b. Remove three nuts (12, figure 4-11) and washers (11) and withdraw MFCU from mounting studs on fuel pump. 4-38. INSTALLATION. a. Install two new packings (8, figure 4-11) on mounting face transfer ports (9).

NOTE


b. Align splines of pump coupling with splines on AFCU drive. Install pump onto AFCU and MFCU assuring that preformed packings are not damaged. Torque four AFCU nuts 75 to 86 inch-pounds. Torque three MFCU nuts 75 to 85 inch-pounds. (QA) c. Assemble MFCU, AFCU and pump to accessory gearbox.

Aviation Turbine Fuel 2 d. Disconnect fuel inlet at flow divider and perform a wet motoring run for depreservation. Carry out adjustments and functional checks. Disconnect fuel flow divider inlet line and perform wet motoring run for depreserving a new replacement fuel control. 4-39. FUEL CONTROL UNIT SOLENOID VALVE. A fuel control unit solenoid valve is located on the left side of each MFCU. Function is to operate a spring loaded valve allowing fuel to flow to the MFCU, at the same time blocking fuel to the AFCU. 4-40. REMOVAL. a. Disconnect electrical connection (10, figure 4-11). b. Remove lockwire, two screws (20) and washers (21). c. Remove solenoid valve (23). 4-41. INSTALLATION. a. Install two new preformed packings (22, figure 4-11) on transfer ports of solenoid valve (23). b. Install solenoid valve (23) on MFCU assuring preformed packings are correctly seated, and secure with screws (20) and washers (21). Torque screws 20 to 25 inch-pounds and lockwire together. (QA) c. Connect electrical connector (10), install fingertight and lockwire. (QA)


4-54

4-42. IGNITION EXCITERS. An ignition exciter unit for each engine power section regulates electrical power to the spark igniters. The exciter unit for each engine power section is located aft of the Station 180.79 intermediate firewall, mounted on inboard side of the firewall brace. 4-43. REMOVAL. (Figure 4-12.)

WARNING

Voltage used in ignition system is dangerously high for personnel.

a. Before disassembling any part of ignition system: Switch ignition OFF and leave system inoperative for at least 6 minutes. Carefully detach coupling nut from spark igniter and ground electrode to gas generator case. b. Disconnect power supply cable from lower end of exciter unit. c. Disconnect two harness cables from upper end of exciter unit. d. Remove four bolts to detach exciter unit from firewall brace. 4-44. INSTALLATION. (Figure 4-12.) a. Position exciter unit with single connector down, on inboard side of brace member at aft side of Station 180.79 firewall. b. Align mounting holes and install four bolts through web of firewall brace and flange of exciter unit. Secure bolts with washers and nuts, torque 25 to 35 inch-pounds. (QA) c. Connect two harness cables to upper end of unit. Install connectors fingertight plus 1/8 turn and Iockwire. (QA) d. Connect power supply cable to lower end of exciter unit. Install connector fingertight plus 1/8 turn and Iockwire. (QA) e. Perform functional check. 4-45. SPARK IGNITERS. The spark igniters, which initiate power section combustion, are

located at 4 o'clock and 11 o'clock position on each gas generator case. 4-46. REMOVAL. (Figure 4-12.)

WARNING

The voltage at spark igniters is dangerously high. Ignition shall be switched to OFF position and ignition system inoperative for at least 6 minutes before removing any ignition system component.

a. Detach spark igniter coupling nut at spark igniter and touch connector contact to spark igniter body shield.

CAUTION

Replace igniter if accidentally dropped. Damage not detectable by test can occur.

b. Hold spark igniter with wrench, while disconnecting harness cable coupling nut. c. Break torque on spark igniter and remove igniter from gas generator case. 4-47. INSTALLATION. (Figure 4-12.) a. Install new copper gasket on spark igniter and install in gas generator boss.

NOTE

Do not use lubricant on silver plated threads.

b. Torque spark igniter to 300 inch-pounds. Loosen to zero inch-pounds and retorque 300 to 360 inch-pounds. (QA) c. Connect harness cable on spark igniter. Install connector fingertight plus 1/8 turn and Iockwire. The lower spark igniter coupling nut is Iockwired to number 7 fuel manifold adapter. (QA) d. Perform functional check.


Change 4 4-55

Figure 4-12. Ignition Exciter Unit and Spark Igniters (Typical)

4-48. COMPRESSOR INLET SCREEN – PRIOR TO PPC NO. 9A. 4-49. REMOVAL. (Figure 4-13.) a. Remove induction baffle panels as necessary for access. Refer to paragraph 4-158. b. Remove two nuts (7), bolts (5) and washers (6) securing ends of inlet screen (4) at 6 o'clock position.

c. Remove screen by passing it carefully between inlet case and tubes. 4-50. INSTALLATION. (Figure 4-13.)

Petrolatum 5 a. Lightly coat rubber rims on air inlet screen (4) with petrolatum, VV-P-236. b. Install screen (4) around inlet case with joint at 6 o'clock position and secure with two bolts (5), washers (6) and nuts (7). Torque nuts 25 to 35 inch-pounds. (QA) c. Install induction baffle panels. Refer to paragraph 4-159. 4-51. COMPRESSOR INLET SCREEN AND COMPRESSOR SPRAY RING – INCORPORATING PPC NO. 9A. 4-52. REMOVAL. (Figure 4-13.) a. Remove induction baffle panels as necessary for access. Refer to paragraph 4-158. b. Disconnect spray ring halves from tee connection (3), and remove tee connection. c. Remove two nuts (7), bolts (5) and washers (6) securing air inlet screen (4) at 6 o'clock position. d. Remove screen (4) by passing it carefully between inlet case and tubes. Remove spray ring halves. 4-53. INSTALLATION. (Figure 4-13.)

Petrolatum 5 a. Lightly coat rubber rim of air inlet screen (4) with petrolatum, VV-P-236, and install screen around inlet case with joint at 6 o'clock position.


4-56 Change 4

Figure 4-13. Compressor Inlet Screen

b. Position spray ring halves around inlet case and connect to tee connection (3, figure 4-13) fingertight. c. Assure tee connection (3) is approxi-mately top center and that all four brackets (1) are trapped under inlet screen and butt against fireseal. d. Secure screen (4) with two bolts (5), washers (6) and nuts (7). Torque nuts 36 to 40 inch-pounds. (QA)

e. Torque spray ring halves to tee connec-tion 275 to 300 inch-pounds, and Iockwire. (QA) f. Install cap (2) on tee connection opening and torque 90 to 100 inch-pounds and Iockwire. (QA) g. Install induction baffle panels. Refer to paragraph 4-159.


Change 4 4-57

4-54. FLOW DIVIDERS. A flow divider is pro-vided on each engine power section, on lower side of the gas generator case, in the metered fuel line upstream of the fuel manifold. 4-55. REMOVAL. (Figure 4-14.)

Aviation Turbine Fuel 2 a. Disconnect drain line from elbow (6) at flow divider (10). b. Disconnect fuel supply line (14). c. Remove four bolts (11) securing flow divider (10) to inlet adapter (16) and remove flow divider (10). d. If unit is to be replaced, remove adapter (13). Loosen nut (7) and unscrew elbow (6) from body of flow divider and retain for replacement of flow divider. 4-56. INSTALLATION. (Figure 4-14.) a. If unit is a replacement item, install new preformed packing (9), new backup ring (8) and nut (7) on elbow (6). Install elbow in fuel flow divider body (10), assure correct alignment and torque nut 38 to 42 inch-pounds and Iockwire. (QA) b. Install adapter (13) with new preformed packing (12) in body of flow divider (10). Torque adapter 65 to 75 inch-pounds. (QA)

Petrolatum 5 c. Moisten two new preformed packings (20) with petrolatum, VV-P-236, and install on face of flow divider (10). Install flow divider on fuel manifold adapter (16) and secure with four bolts (11). Torque bolts 32 to 36 inch-pounds and lockwire in pairs. (QA)

d. Connect fuel inlet tube (14) to adapter (13) and overboard line to elbow (6). Torque connec-tions 90 to 100 inch-pounds and lockwire. (QA) 4-57. FUEL MANIFOLD ADAPTER ASSEMBLY. 4-58. REMOVAL. (Figure 4-14.) a. Tag each adapter to assure correct loca-tion on assembly. See figure 4-14 for location markings.

NOTE

Spark igniters shall be left in place to maintain combustion chamber in correct position.

b. Disconnect ignition leads at igniters.

Aviation Turbine Fuel 2 c. Disconnect fuel inlet connection (14) and drain line form elbow (6) at fuel flow divider (10). d. Remove four bolts (11) securing flow divider (10) to inlet manifold adapter (16) and remove flow divider. e. Remove two bolts (5) and locking plates (3) from each manifold adapter (18) and inlet adapter (16).

NOTE

Because of the arrangement of the manifold adapters, it is not possible to slide out all the transfer tubes prior to removing the adapters. Adapter orifices which allow greatest transfer tube movement are identified in figure 4-14.

f. Starting at No. 1 location, push transfer tubes (17) into manifold adapters as far as they will go.


4-58

Figure 4-14. Flow Divider, Fuel Manifold Adapter and Nozzles


Change 4 4-59

g. Starting at No. 8 location, raise manifold adapter from gas generator slightly until resist-ance is felt. Repeat with remaining adapters in sequence, raising each adapter until resistance is felt or until free to lift away. h. Carefully remove any gaskets adhering to gas generator case bosses. If necessary, use a wooden spatula to avoid damage to bosses. i. Remove transfer tubes (17, figure 4-14) from manifold adapters. 4-59. INSTALLATION. (Figure 4-14.)

Petrolatum 5

Sealing Compound 6 a. Lubricate preformed packings with petro-latum, VV-P-236. If pre-PPC No. 57 gaskets are used, lightly coat each face of gasket with sealing compound, DC4. b. Install two preformed packings (20) on face of flow divider (10) and install flow divider on inlet manifold adapter (16) and secure with four bolts (11). Torque bolts 32 to 36 inch-pounds and Iockwire. (QA) c. Install 56 new preformed packings (15) on transfer tubes (17). d. Assure faces of gas generator fuel manifold adapter bosses are clean. Install new gaskets (2) on each of 14 manifold adapters.

NOTE

Wear on fuel transfer tube locking flange should not exceed 0.010 inch deep. Fuel transfer tubes, 3011155, exhibiting excessive fretting damage may be replaced with stainless steel transfer tubes, 3122839-01. However, paired tubes installed between each adapter assembly must be the same part number.

e. Install four transfer tubes (17) in inlet manifold adapter (16) and install adapter at No. 8 location. Secure loosely with two bolts (5). Do not tighten bolts at this stage.

NOTE

On T400-CP-400 engines, primary mani-fold adapter assemblies are identifiable by a single weld blob or a plug on the larger mounting flange. Other weld blobs appearing on the adapter are to be ignored.

f. Install No. 7 location manifold adapter (18) on correct boss in gas generator case, aligning transfer tubes (17) in previously installed manifold adapter (18), and push transfer tubes in ports of No. 7 adapter. g. Install two transfer tubes (17) in installed No. 7 adapter. h. Carry out steps f. and g., preceding, for remainder of manifold adapters in sequence of 6, 5, 4, 3, 2, 9, 10, 11, 12, 13 and 14. i. Install No. 1 location manifold adapter in boss on gas generator case. Align transfer tubes (17) already installed in adapters No. 2 and 14 and push into No. 1 adapter. If difficulty is experienced in aligning transfer tubes, lift adapters at No. 2 and 14 locations approximately 0.500 inch away from gas generator case or until transfer tubes enter manifold adapter. j. Remove temporary bolts (5) securing inlet manifold adapter (16) at No. 8 location.

NOTE

If pre-PPC No. 57 gaskets, 3011157, are used, bolts (5) shall be retorqued after engine test and secured with Iockwire.

k. Secure each manifold adapter with locking plate (3) and two bolts (5) on T400-CP-400 power sections, prior to Serial No. 64558 and not incorporating PPC No. 45, installing bracket (4) at location 8. Install bracket (19) at location 9. Torque bolts 32 to 36 inch-pounds. (QA) I. Connect fuel supply line and fuel drain line to flow divider. Torque connections 90 to 100 inch-pounds and secure with Iockwire. (QA)


4-60 Change 5

m. Connect ignition leads to spark igniters. Torque connections fingertight plus 1/8 turn and Iockwire. (QA) 4-60. COMBUSTION CHAMBER DRAIN VALVES. Combustion chamber drain valves are located at 6 o'clock positions of each gas generator case. Function is to drain unused fuel from combustion chamber after power section shut-down. 4-61. REMOVAL. (Figure 4-15.)

Aviation Turbine Fuel 2 a. Disconnect drain line (1) from combustion chamber drain valve (2). b. Remove drain valve from gas generator case. c. Remove gasket (3) from valve body. 4-62. CLEANING. (Figure 4-15.) a. Remove spiral Iockring (4) and withdraw valve (5) and spring (6) from valve body (2).

Dry Cleaning Solvent 7 b. Thoroughly clean body, valve and spring by washing in drycleaning solvent, MIL-PRF-680, Type II, using a stiff bristled nylon brush if required.

Lapping Compound 18 c. Lap valve in valve body, using lapping compound, MIL-L-17862, to eliminate possibility of leakage. Wash parts with drycleaning solvent to remove all traces of lapping compound.

d. Inspect tension of spring (6) by applying a load of 4 to 8 ounces for a maximum increase in length of 0.250 inches, reject spring if outside limits. Install spring (6) and valve (5) in valve body (2) and secure with new retaining ring (4). (QA) 4-63. INSTALLATION. (Figure 4-15.) a. Install combustion chamber drain valve body complete with new gasket (3) in boss on gas generator case. Torque valve 450 to 550 inch-pounds. Retorque and Iockwire after first engine run. (QA) b. Install helicopter drain line (1) at combustion chamber drain valve. Torque fitting 40 to 65 inch-pounds. Secure with Iockwire. (QA) 4-64. POWER TURBINE (Nf) GOVERNORS. Power turbine governors are mounted on rear of reduction gearbox. Function is to regulate fuel flow, in conjunction with automatic fuel control units, to maintain rpm of power turbines at desired value in fuel system automatic mode. 4-65. REMOVAL. (Figure 4-16.) a. Disconnect control tube from lever (7) on power turbine governor and Pg tube (1) from elbow (2). b. Remove four nuts (4) and washers (5) securing power turbine (3) to reduction gearbox. c. Withdraw power turbine governor over studs. Remove and discard mounting face gasket (6). d. If power turbine governor is to be replaced by a new item, loosen nut (10) and unscrew elbow (2) from governor body. Remove lever (7) from control shaft, and coupling (11) from governor. Retain items for replacement. 4-66. CLEANING Nf GOVERNOR ORIFICE. (Figure 4-16.) a. Remove power turbine governor in accor-dance with paragraph 4-64. b. Cut Iockwire and remove cap screw (14).


4-61

Figure 4-15. Combustion Chamber Drain Valve


4-62

Figure 4-16. Power Turbine Governor


Change 4 4-63

CAUTION

Do not loosen screw (16, figure 4-16) or turn orifice (17) in clamp (15) during following step.

c. Pull out orifice (17), screw (16) and clamp (15) as a complete assembly. Discard two preformed packings (18 and 19).

NOTE

Preformed packing (19) will have to be removed from casting bore.

d. Clean orifice (17) taking care not to enlarge the inside diameter. e. Insert a small, soft brush through the orifice mounting hole and clean face of lever assembly inside the governor. f. Insert a new preformed packing (19) into the orifice casting bore. Assure it is positioned at bottom of orifice hole. (QA) g. Install a new preformed packing (18), in orifice (17) seal groove, and insert the complete assembly into casting bore. h. Install capscrew (14). Torque 9 to 10 inch- pounds and lockwire. (QA) i. Install power turbine governor on engine. Refer to paragraph 4-64. j. Adjust and perform governor matching. 4-67. INSTALLATION. (Figure 4-16.) a. If power turbine governor is a new item, install elbow (2) with new preformed packing (8), new backup ring (9) and nut (10) in body of governor, assuring correct alignment of elbow (2). Install lever (7) on governor control shaft.

CAUTION

Do not attempt to adjust minimum stop (13).

b. Install coupling (11) on accessory drive splines of reduction gearbox. c. Install over studs, one gasket (6) when installing left side power turbine governor and two new gaskets (if using unmodified cover) when installing right side power turbine governor. d. Install governor (3) over studs and secure with four nuts (4) and washers (5). Torque nuts 55 to 65 inch-pounds. (QA) e. Connect Pg tube (1) to elbow (2) and torque nut (10) 40 to 60 inch-pound. Torque connection (1) 90 to 100 inch-pounds and lockwire. Reconnect control tube to lever (7). (QA) f. Adjust and perform governor matching.

WARNING

Integrity of Pg control lines and TCU is essential, as a leak can result in power loss to one or both engines to an idle condition.

4-68. TORQUE CONTROL. The torque control is located on top of the reduction gearbox. Function is to regulate fuel flow, in conjunction with automatic fuel control units, to maintain power section output torques equal within maximum limit. 4-69. REMOVAL. (Figure 4-17.) a. On reduction gearboxes incorporating PPC No. 65, remove nut (14), bolt (15) and washers (16) securing clamps (13). Remove clamps (13). b. Disconnect two Pg tubes (7) from adap-ters (11). c. Disconnect two oil tubes (2) from elbows (3). d. Remove three nuts (1) and washers (12) and withdraw torque control unit from studs. e. If unit is to be replaced by a new item, loosen nuts (4) and remove both elbows (3). Remove adapters (11) and retain for replacement unit.


4-64

Figure 4-17. Torque Control Unit


Change 4 4-65

4-70. TORQUE CONTROL UNIT PRIMING - PRIOR TO PPC NO. 70. a. Remove torque control unit from reduction gearbox. Refer to paragraph 4-68. b. Connect a 20 to 24 inch length of 0.250 inch clear plastic tubing, MIL-P-22296, (figure 4-18) capable of withstanding 75 psig to Tp2 port.

Lubricating Oil 1 c. Fill tube with lubricating oil, MIL-PRF-23699. Tap tube to release any air trapped in tube. Connect tube to an air pressure source. d. With Tp2 port uppermost and tube vertical, slowly increase air pressure to 47±2 psig and maintain this position for 10 seconds. e. Rotate torque control so that adjustment screws are uppermost. f. Hold for 10 seconds and tap control and tube to free entrapped air from bellows. g. Turn control so that Pg1 port is upper-most. Repeat step f. preceding. h. With Pg1 port still uppermost, slowly re-lease air pressure (approximately 30 seconds). i. Turn control so that Tp2 port is upper-most. j. Repeat step f. preceding. k. Repeat steps c. through j. until bellow assemblies are completely filled with oil, which will be evident when air is no longer seen escaping from bellows. I. Disconnect air supply and remove tube. m. Check that oil level is between bottom and third threads.

n. Cap off Tp2 port with suitable plug (AN814-4D or -4DL) and preformed packing (MS9387-04) to prevent loss of oil while re-peating the procedure on the Tp1 bellows. o. For Tp1 port repeat steps b. through f. p. Turn control so to Pg2 port is uppermost. Repeat step f. preceding. q. With Pg2 port still uppermost, slowly release air pressure (approximately 30 seconds). r. Turn control so that Tp1 port is upper-most. s. Repeat step f. preceding. t. Repeat steps o. through s. until bellows assemblies are completely filled with oil. Add oil as necessary. u. Disconnect air supply and remove tube. v. Assure that oil level in Tp1 and Tp2 ports is between bottom and third thread. Add oil as necessary. w. Cap off ports to prevent leakage. x. Install torque control unit on reduction gearbox. Refer to paragraph 4-68.

NOTE

Assure oil lines to torque control are filled with oil prior to installation on gearbox.

4-71. TORQUE CONTROL UNIT PRIMING – INCORPORATING PPC NO. 70.

NOTE

It is recommended that a 20cc hypodermic syringe with a No. 18 needle be used to fill Tp1 and Tp2 bellows with lubricating oil, MIL-PRF-23699, but any suitable alternative method is acceptable.

a. Remove blanking plugs from Tp1 and Tp2 ports (figure 4-19).


4-66 Change 6

Figure 4-18. Torque Control Unit Priming Circuit (Pre-PPC No. 70)

NOTE

Do not reinstall bleed assemblies in TP1 and TP2 ports.

b. Remove bleed assemblies if present (step 1) and discard. c. Install blanking plugs in ports. d. Place unit on a flat surface with oil filling port on Tp1 side uppermost. e. Remove oil filler plug.

Lubricating Oil 1 f. Draw 10cc of lubricating oil, MIL-PRF-23699, into syringe. g. Insert needle into oil filling port until tip rests lightly on the bottom of bellows. h. Slowly inject oil into bellows.


4-67

Figure 4-19. Torque Control Unit Priming Circuit (Post PPC No. 70)


4-68 Change 6

NOTE

Assure that needle remains on the bottom of bellows to minimize the possibility of air entering the oil stream from needle.

i. Inject oil until level A is reached (step 2). j. Inject oil at a considerably reduced rate to allow threaded orifices to fill until level B is reached. k. Fill oil filling port to top of threads (level C). I. Install oil filler plug with new preformed packing and torque 35 to 40 inch-pounds. (QA) m. Turn unit so that Tp ports are uppermost. n. Remove blanking plug from Tp1 port and add or remove oil to level shown in step 3. o. Deleted p. Deleted

NOTE

Do not reinstall bleed assemblies in TP1 and TP2 ports.

q. Top up Tp1 port. r. Install Tp1 blanking plug and preformed packing to prevent loss of oil. s. Repeat above procedure for Tp2 bellows. 4-72. INSTALLATION. (Figure 4-17.) a. If unit is a replacement item, install new preformed packings (6), new backup rings (5) and nuts (4) on each elbow (3) and install in torque control unit. Assure correct alignment.

Petrolatum 5 b. Moisten new preformed packings (10) with petrolatum, VV-P-236, install on two adapters (11) and install in torque control unit. Torque adapters 40 to 65 inch-pounds. (QA) c. Assure torque control unit has been primed per paragraph 4-70 and install unit over studs (9) on reduction gearbox and secure with three washers (12) and nuts (1). Torque nuts 32 to 36 inch-pounds. (QA) d. Assure torque pressure tubes (2) are filled with oil and connect to elbows (3). Align elbows (3) and torque nuts (4) 40 to 60 inch-pounds. Torque oil tube connections 90 to 100 inch-pounds and lockwire. (QA) e. Connect two Pg pressure tubes (7) to adapters (11). Torque connections 90 to 100 inch-pounds and lockwire. (QA)

NOTE

The three washers are interposed between the two clamps.

f. On reduction gearboxes incorporating PPC No. 65, install clamps (13) on Pg tubes (7) and oil tubes (2). Secure with nut (14), bolt (15) and washers (16). Torque nut 36 to 40 inch-pounds. (QA) g. Accomplish operational check and adjustment.


Change 5 4-69

4-73. P3 TUBE FROM AFCU TO GAS GENERATOR CASE. 4-74. REMOVAL. a. AFCU to Front Fireseal. (Figure 4-20.) 1. Disconnect P3 tube (9) at AFCU connection and tee-connection (8). Remove tube. 2. Disconnect P3 tube (7) at AFCU connection (6). 3. Remove bolt (1) and nut (5) securing double clamp (3) to bracket (2). 4. Remove bolts (10) and nuts (12) securing clamps (11) to bracket (13). 5. Remove bolt (30) and nut (31) securing clamp (32) to bracket (34). 6. Disconnect tube (7) at elbow (14). Remove tube (7) from double clamps (3 and 11). b. Front Fireseal to Gas Generator Case. (Pre-PPC 85.) (Figure 4-20.) 1. Remove two bolts (16) and nuts (17) securing plate (19), insulations (20) and seal (21) to center fireseal. 2. Disconnect tube assembly (18) at coupling nut (15). 3. Remove P3 filter cover (28), packings (24 and 26) and element (25). 4. Remove two bolts (23) securing filter housing (29) to gas generator case. 5. Remove plate (19), insulations (20) and seal (21). Withdraw tube assembly (18) through center fireseal. c. Front Fireseal to Gas Generator Case. (PPC 85.) (Figure 4-20A.) 1. Remove nuts (19) and bolts (23) securing retaining plate (20), insulations (21) and seal (22) to center fireseal. 2. Remove bolts (1) securing filter housing assembly (3) to gas generator case.

3. Disconnect tube (24) at coupling nut (26). 4. Remove tube assembly (24) through center fireseal. Remove and discard gasket (2). 5. Remove retaining plate (20), insulations (21) and seal (22) from tube (24). 6. Remove bolts (27) securing tube assembly (24) to filter housing assembly (3). Remove and discard gasket (28). 7. Remove filter cover (5) and filter element (12) from filter housing assembly (3). Remove and discard preformed packings (4, 11 and 13). 8. Remove adapter (8) from filter cover (5). 9. Remove and discard preformed packing (7). 10. Remove retaining ring (10) and withdraw drain valve (9) and spring (6) from adapter (8). 4-75. INSTALLATION. a. Gas Generator Case to Front Fireseal. (Pre-PPC 85.) (Figure 4-20.) 1. Insert filter housing (29) through center fireseal and align bolt holes in filter housing (29) with corresponding holes in gas generator case. 2. Install new gasket (22) (with ridge toward gas generator case) on filter housing (29) and secure with two bolts (23) to gas generator. Torque bolts 32 to 36 inch-pounds. (QA) 3. Install seal (21), insulations (20) and plate (19) on tube assembly (18) and secure with two bolts (16) and nuts (17). Install nuts to firm contact plus 1/2 turn. (QA) 4. Connect tube assembly (18) at coupling nut (15), torque connection 90 to 100 inch-pounds and lockwire. (QA) 5. Install packing (24) in recess of filter element (25) and install element in filter housing (29).


4-70 Change 5

6. Install packing (26) on filter cover (28) and install cover (28) on filter housing (29). 7. Install cover (28) until metal-to-metal contact and lockwire. Do not overtorque. Do not exceed 25 inch-pounds. b. Gas Generator Case to Front Fireseal. (PPC 85.) (Figure 4-20A.)

Lubricating Oil 1 1. Install preformed packing (7) on adapter (8). 2. Install spring (6) and drain valve (9) into adapter (8) and secure with retaining ring (10). 3. Install adapter (8) into filter cover (5). Torque adapter 225 to 250 inch-pounds and lockwire. (QA) 4. Install spring (14) into filter element (12). 5. Lubricate preformed packing (13) with engine oil and install over spigot of filter housing assembly (3). 6. Install preformed packing (11) onto boss of filter element (12) in bottom groove furthest from face of filter element. 7. Install preformed packing (4) in groove of filter cover (5). 8. Apply engine oil to threads on filter cover (5). 9. Install filter (12) and filter cover (5). Torque cover (5) 60 to 70 inch-pounds and lockwire. (QA) 10. Secure new gasket (28) (with ridge toward filter housing) and tube assembly (24) flange to filter housing assembly (3) using bolts (27). Torque bolts 15 to 20 inch-pounds, then without slackening, final torque bolts 32 to 36 inch-pounds and lockwire. (QA) 11. Install retaining plate (20), insulations (21) and seal (22) on tube assembly (24) in correct order. Ensure the bolt holes and tube holes align.

12. Install tube assembly (24) through center fireseal. 13. Install new gasket (2) over port in gas generator case with gasket ridge against case (Detail C). Position filter housing assembly (3) with bolts (1). Torque bolts 15 to 20 inch-pounds, then without slackening, final torque bolts 32 to 36 inch-pounds and lockwire. (QA) 14. Align holes in retaining plate (20), insulations (21) and seal (22) and secure to center fireseal mount ring with bracket (18), bolts (23) and nuts (19). Tighten nuts to firm contact plus 1/2 turn. (QA) 15. Install clamp (16) on tube (24) and secure to bracket (18) with bolt (17) and nut (15). Torque nut 25 to 30 inch-pounds. (QA) 16. Tighten tube coupling nut (26) on elbow (25). Torque connection 90 to 100 inch-pounds and lockwire. (QA) c. Front Fireseal to AFCU. (Figure 4-20.) 1. Install tube (7) and connect to elbow (14), and AFCU connection (6). Torque connections 90 to 100 inch-pounds and lockwire. (QA) 2. Install clamp cushion (33) and clamp (32) on tube (7) and secure to bracket (34) with bolt (30) and nut (31). Torque nut 25 to 30 inch-pounds. (QA) 3. Install clamps (11) on tube (7) and secure to bracket (13) with nuts (12) and bolts (10). Torque nuts 25 to 30 inch-pounds. (QA) 4. Install clamps (3) and spacer (4) on tube (7) and secure to bracket (2) with bolt (1) and nut (5). Torque nut 25 to 30 inch-pounds. (QA) 5. Connect tube (9) to AFCU and tee connection (8). Torque connections 90 to 100 inch-pounds and lockwire. (QA) 6. Carry out pressure test. 4-76. PRESSURE TESTING AIR SUPPLY SYS-TEMS. (Figure 4-20.) a. Disconnect tube assembly (18) from elbow (14).


Change 5 4-70A

Figure 4-20. P3 Tube from AFCU to Gas Generator Case


4-70B Change 5

Figure 4-20A. P3 Tube from Front Fireseal to Gas Generator Case (PPC 85)


Change 5 4-71

WARNING

High pressures used during testing may cause rupturing or bursting of faulty tubes and hoses. The result could be serious injury. To prevent injury, cover air tubes and hoses with a suitable safety shield during testing. When caps or plugs are used, assure they are securely installed to prevent them from being blown out. Assure that pressures are bled off before exposing or touching hoses or tubes.

b. Connect a supply of clean, dry air at 75 to 85 psi to elbow (14, figure 4-20).

Leak Detection Compound 20 c. Apply leak checking fluid, Leak Tec 372 (CAGE 03530) or equivalent, to entire surface of connecting points. No leaks are permitted other than from the following: bleed hole in base of AFCU, perforated plate on side of AFCU, bleed hole at air inlet connection to AFCU, vent holes in torque control unit, vent holes in power turbine governor cover. d. If no leaks are found, wipe all leak-detecting fluid from connections. e. If leaks are found, part of connection shall be examined for defects and retorqued. Repeat leak check. f. Disconnect air supply and reconnect assembly (18) to elbow (14). Torque connections 90 to 100 inch-pounds and lockwire. (QA) 4-77. P3 TUBE TO REDUCTION GEARBOX. 4-78. REMOVAL. (Figure 4-21.) a. Remove nut (9) and bolt (6) securing clamp (7) to ignition harness (8) clamp. b. Remove nut (16) and bolt (10) securing clamp (11) to clamp on trim cable (13).

c. Remove nut (14) and bolt (17) securing clamp (15) to clamp on trim cable (13). d. Disconnect tube (12) at connection to elbow (3) or tee fitting (2) and adapter (18). Remove tube. e. Remove nut (22) and bolt (20) securing doubler clamp (21). f. Remove nut (23) and bolt (26) securing clamp (24) to bracket (25). g. Disconnect tube (27) at connection to adapter (18) and P3 valve housing (28). Remove tube from double clamp (21). h. Disconnect P3 tube (30) at tee connection (31). Disconnect P3 valve housing (28) and spring (29) from P3 tube (30). i. Disconnect tube (32) at tee-connection (31) and tee-connection (33). Remove tube. j. Remove nut (44) and bolt (42) securing double clamp (45). k. Remove nut (47) and bolt (43) securing clamp (46) to bracket (48). I. Remove nut (40) and bolt (35) securing clamp (41) to bracket (39). m. Disconnect tube (38) at P3 valve housing (37) and adapter (50). Remove tube. n. Disconnect P3 tube (34) at tee connection (33). Disconnect P3 valve housing (37) and spring (36) from P3 tube (34). 4-79. INSTALLATION. (Figure 4-21.) a. Install spring (36) in P3 valve housing (37), assure spring seats in housing groove, and connect tube (34) to P3 valve housing (37). Torque connection 225 to 250 inch-pounds and lockwire. (QA) b. Connect P3 tube (34) to tee connection (33). Torque 65 to 75 inch-pounds and Iockwire. (QA)


4-72

Figure 4-21. P3 Tube to Reduction Gearbox


Change 4 4-73

c. Connect tube (38, figure 4-21) to P3 valve housing (37) and adapter (50). Torque connec-tions 90 to 100 inch-pounds. (QA) d. Install clamp (46) on tube (38) and secure with trim cable clamp, to bracket (48) with nut (47) and bolt (43). Torque nut 25 to 30 inch-pounds. (QA) e. Install clamp (45) on tube (38) and secure with nut (44) and bolt (42). Torque nut 25 to 30 inch-pounds. (QA) f. Install clamp (41) on tube (38) and bracket (39) and secure with nut (40) and bolt (35). Torque nut 25 to 35 inch-pounds. (QA) g. Connect tube (32) to tee-connection (31) and tee-connection (33). Torque connections 90 to 100 inch-pounds and lockwire. (QA) h. Install spring (29) in P3 valve housing (28), assure spring seats in housing groove, and connect tube (30) to P3 valve housing (28). Torque connection 225 to 250 inch-pounds and lockwire. (QA) i. Connect P3 tube (30) to tee connection (31). Torque 65 to 75 inch-pounds and lockwire. (QA) j. Connect tube (27) to P3 valve housing (28) and adapter (18). Torque connection 90 to 100 inch-pounds and Iockwire. (QA) k. Install clamp (21) on tube (27) and cable (13), and secure with nut (22) and bolt (20). Torque nut 25 to 30 inch-pounds. (QA) I. Install clamp (24) on tube (27) and bracket (25) and secure with nut (23) and bolt (26). Torque nut 25 to 35 inch-pounds. (QA) m. Connect tube (12) to elbow (3) or tee fitting (2) and adapter (18). Torque connections 90 to 100 inch-pounds and lockwire. (QA) n. Install clamp (15) on tube (12) and secure to clamp on trim cable (13) with nut (14) and bolt (17).

o. Install clamp (11) on tube (12) and secure to clamp on trim cable (13), with nut (16) and bolt (10). Torque nut 25 to 30 inch-pounds. (QA) p. Install clamp (7) on tube (12) and secure to clamp on ignition harness (8) with nut (9) and bolt (6). Torque nut 25 to 30 inch-pounds. (QA) 4-80. TORQUE PRESSURE OIL TUBES. 4-81. REMOVAL. (Figure 4-17.) a. On reduction gearboxes incorporating PPC No. 65, remove nut (14), bolt (15) and washers (16) securing clamps (13). Remove clamps (13). b. Remove oil tubes (2) from torque control unit elbow (3) and reduction gearbox torque-meter pressure adapter. 4-82. INSTALLATION. (Figure 4-17.)

Lubricating Oil 1 a. Assure pressure tubes are filled with oil, MIL-PRF-23699, and connect oil pressure tubes to elbow (3) and reduction gearbox torquemeter pressure adapter. Torque connections 90 to 100 inch-pounds and Iockwire. (QA)

NOTE

The three washers are interposed between the two clamps.

b. On reduction gearboxes incorporating PPC No. 65, install clamps (13) on Pg tubes (7) and oil tubes (2). Secure with nut (14), bolt (15) and washers (16). Torque nut 36 to 40 inch-pounds. (QA) 4-83. NO. 2 BEARING SCAVENGE OIL TUBE. 4-84. REMOVAL. (Figure 4-22.) a. Remove two bolts (24) and washers (25) securing elbow (26) to gas generator case and withdraw elbow No. 2 bearing scavenge oil tube (60).


4-74 Change 5

b. Remove four bolts (58, figure 4-22) and nuts (53) securing bracket (57), plate (56), insulations (55) and seal (54) to front fireseal. c. Remove six bolts (29 and 30) and nuts (36 and 38) securing two plates (31 and 34), plate (22), insulations (33) and seal (32) to center fireseal. d. Withdraw No. 2 bearing scavenge oil tube (60) through center fireseal. 4-85. INSTALLATION. (Figure 4-22.) a. Insert tube (60) through plates (31 and 34), insulations (33), seal (32) and center fireseal. Continue to insert tube (60) through plate (56), insulations (55) end seal (54).

Lubricating Oil 1 b. Lubricate two new packings (59) with engine oil, MIL-PRF-23699, and install on tube (60). c. Insert end of tube (60), through front fire-seal, into boss on accessory gearbox. d. Install new gasket (27) and packing (28) on elbow (26). e. Install elbow (26) on end of tube (60) and position elbow in boss of gas generator case. Secure elbow with two washers (25) and bolts (24). Torque bolts 32 to 36 inch-pounds and lockwire. (QA) f. Secure bracket (37), plate (22), plates (31 and 34), insulations (33) and seal (32) to center fireseal with six bolts (29 and 30) and nuts (36 and 38). Torque nuts (36) to firm contact plus 1/2 turn, and nuts (38) 32 to 36 inch-pounds. (QA) g. Secure bracket (57), plate (56), insulations (55) and seal (54) to front fireseal with four bolts (58) and nuts (53). Install nuts to firm contact plus 1/2 turn. (QA)

4-86. PRESSURE OIL TUBE FROM REDUCTION GEARBOX. 4-87. REMOVAL. (Figure 4-23.) a. Remove two bolts (7) and nuts (11) securing plate (8), insulation (9) and seal (10) to center fireseal. b. Remove two bolts (6), washers (2) and nuts (1) securing plate (5), insulations (4) and seal (3) to flange G fireseal. c. Remove two bolts (40) and washers (39) securing elbow (38) to accessory gearbox and remove elbow. d. Remove plates, insulation and seals from tube (12) and withdraw tube through flange G fireseal. e. Remove two bolts (25 and 26) securing tube stop (27 or 42), bracket (28) and flowmeter support bracket (30) to tee-assembly (34) and remove tube stop. f. Remove bolt (14) and nut (13) securing clamp (16) to bracket (15) and remove clamp (16). g. Remove two bolts (18) and nuts (22) securing plate (21), insulation (20) and seal (19) to flange A fireseal. h. Remove two bolts (35) and washers (36) securing flowmeter bracket (30) and tee-assembly (34) to gas generator case and remove tee-assembly. i. Withdraw oil pressure tube (17), through center fireseal until end is clear of flange A fireseal, turn tube (17) to clear flange A fireseal and remove from power section. j. Remove plate, insulation and seal from tube (17).


4-75

Figure 4-22. No. 2 Bearing Scavenge, Pressure Transfer and Scavenge Oil Tubes


4-76

Figure 4-23. Pressure Oil Tube From Reduction Gearbox


Change 4 4-77

4-88. INSTALLATION. (Figure 4-23.) a. Install plate (21), insulations (20) and seal (19) on tube (17).

Lubricating Oil 1 b. Install retainer (24) and preformed packings (23 and 29) on tube (17). Lightly lubricate packings with engine oil, MIL-PRF-23699. c. Insert end of tube (17) through center fireseal. Align other end of tube with boss on reduction gearbox, insert tube through flange A fireseal and into boss. d. Install new gasket (31) and new packing (32) on tee-assembly (34), and insert end of tube (17) into assembly (34). Insert assembly (34) into gas generator case boss. e. Install bracket (30) on tee-assembly (34) and secure with two washers (36) end bolts (35). f. Secure tube stop (27 or 42), bracket (28) and bracket (30) to tee-assembly (34) with two bolts (25 and 26). (QA) g. Torque bolts (35) 32 to 36 inch-pounds and lockwire. (QA) h. Torque bolts (25 and 26) 32 to 36 inch-pounds and lockwire. (QA) i. Install clamp (16) on tube (17) and secure to bracket (15) with bolt (14) and nut (13). Torque nut 25 to 35 inch-pounds. (QA) j. Secure plate (21), insulations (20) and seal (19) to flange A with two bolts (18) and nuts (22). Install nuts to firm contact plus 1/2 turn. (QA) k. Install two new packings (33 and 37) on tube (12).

I. Insert tube (12) through flange G fireseal, and install plates (5 and 8), insulation (4 and 9) and seals (3 and 10) on tube. Insert tube into the assembly (34). m. Install new packings (41) on elbow (38). n. Install elbow (38) on tube (12) and secure elbow to accessory gearbox with two washers (39) and bolts (40). Torque bolts 32 to 36 inch-pounds and lockwire. (QA) o. Secure plate (5), insulations (4) and seal (3) to flange G fireseal with two bolts (6), washers (2) and nuts (1). Install nuts to firm contact plus 1/2 turn. (QA) p. Secure plate (8), insulations (9) and seal (10) to center fireseal with two bolts (7) and nuts (11). Install nuts to firm contact plus 1/2 turn. (QA) 4-89. SCAVENGE OIL TUBE. 4-90. REMOVAL. (Figure 4-22.) a. Remove two bolts (41) and nuts (43) securing retaining plate (4) to rear bulkhead. b. Remove two bolts (14) and nuts (10) securing mounting bracket (8) to positioning plate (13). c. Withdraw tube (5) forward until end is clear of rear fireseal, turn tube sufficiently to clear fireseal and remove tube. d. Remove bolt (6), nut (9), clamp (7) and bracket (8) from tube (5). e. Remove six bolts (29 and 30) and nuts (36 and 38) securing bracket (37), plate (22), plates (31 and 34), insulations (33) and seal (32) to center fireseal. f. Remove three bolts (48) and nuts (52) securing plate (49), insulations (50) and seal (51) to front fireseal. g. Withdraw tube (45) from power section.


4-78 Change 4

4-91. INSTALLATION. (Figure 4-22.)

Lubricating Oil 1 a. Install new packing (46) on tube (45). Lubricate packing with engine oil, MIL-PRF-23699. b. Install tube (45) through center fireseal and align other end with boss on accessory gearbox. c. Install plate (49), insulations (50) and seal (51) over end of tube (45). Insert tube through front fireseal and into boss on accessory gearbox. d. Install plates (31 and 34), seal (32), insulations (33) and plate (22) over end of tube (45) and secure to center fireseal, including bracket (37), with six bolts (29 and 30) and nuts (36 and 38). Assure sealing ring (23) is positioned correctly. Install nuts (36) to firm contact plus 1/2 turn, and torque nuts (38) 32 to 36 inch-pounds. (QA) e. Secure plate (49), insulations (50) and seal (51) to front fireseal with three bolts (48) and nuts (52). Install nuts to firm contact plus 1/2 turn. (QA) f. Install retaining ring (19) and new packing (20) on tube (5). Lightly lubricate packing with engine oil, MIL-PRF-23699. g. Insert tube (5) into tube (45) and align other end of tube (5) with transfer tube (1). h. Install new packing (2) on transfer tube (1), and insert tube (5) through plate (4) and over transfer tube (1). Assure sealing ring (3) is positioned correctly in plate (4). i. Secure bracket (8) to positioning plate (13) with two bolts (14) and nuts (10). Torque nuts 25 to 35 inch-pounds. (QA)

j. Install clamp (7) on tube (5) and secure to bracket (8) with bolt (6) and nut (9). Torque nut 25 to 35 inch-pounds. (QA) k. Secure plate (4) to rear bulkhead with two bolts (41) and nuts (43). Torque nuts 25 to 35 inch-pounds. (QA) 4-92. PRESSURE OIL TUBE TO REDUCTION GEARBOX. 4-93. REMOVAL. (Figure 4-22.) a. Remove two bolts (41) and nuts (43) securing retaining plate (4) to rear bulkhead. b. Remove two bolts (15) and nuts (11) securing mounting bracket (12) to positioning plate (13). c. Withdraw tube (40) forward until end is clear of rear fireseal, turn tube sufficiently to clear fireseal and remove tube. d. Remove bolt (18), nut (16), clamp (17) and bracket (12) from tube (40). e. Remove six bolts (29 and 30) and nuts (36 and 38) securing bracket (37), plate (22), plates (31 and 34), insulation (33) and seal (32) to center fireseal. f. Remove four bolts (58) and nuts (53) securing bracket (57), plate (56), insulation (55) and seal (54) to front fireseal. g. Withdraw tube (44) from power section. 4-94. INSTALLATION. (Figure 4-22.)

Lubricating Oil 1 a. Install new packing (47) on tube (44). Lightly lubricate packing with engine oil, MIL-PRF-23699. b. Install tube (44) through center fireseal and align other and with boss on accessory gearbox.


Change 5 4-79

c. Install plate (56, figure 4-22), insulation (55) and seal (54) over end of tube (44). Insert tube through front fireseal into boss on accessory gearbox. d. Install plates (31 and 34), seal (32), insu-lation (33) and plate (22) over end of tube (44) and secure to center fireseal, including bracket (37), with six bolts (29 and 39) and nuts (36 and 38). Assure sealing ring (23) is positioned correctly. Install nuts (36) to firm contact plus 1/2 turn and torque nuts (38) 32 to 36 inch-pounds. (QA) e. Secure bracket (57), plate (56), insulations (55) and seal (54) to front fireseal with four bolts (58) and nuts (53). Install nuts to firm contact plus 1/2 turn. (QA)

Lubricating Oil 1 f. Install retaining ring (39) and new packing (21) on tube (40). Lubricate packing with engine oil, MIL-PRF-23699. g. Insert tube (40) into tube (44) and align other end of tube with transfer tube (1). h. Install new packing (2) on transfer tube (1), and insert tube (40) through plate (4) and over transfer tube (1). Assure sealing ring (42) is positioned correctly in plate (4). Lubricate packing with engine oil, MIL-PRF-23699. i. Secure bracket (12) to positioning plate (13) with two bolts (15) and nuts (6). Torque nuts 25 to 35 inch-pounds. (QA) j. Install clamp (17) on tube (40) and secure to bracket (12) with bolt (18) and nut (16). Torque nut 25 to 35 inch-pounds. (QA) k. Secure plate (4) to rear bulkhead with two bolts (41) and nuts (43). Torque nuts 25 to 35 inch-pounds. (QA)

4-95. PRESSURE OIL SENSE LINE TO CHECK AND RELIEF VALVE. 4-96. REMOVAL. (Figure 4-24.) Disconnect tube (15) at tee (13) and check valve elbow (17). Remove tube. 4-97. INSTALLATION. (Figure 4-24.) Connect tube (15) to tee (13) and check valve elbow (17). Torque connections 90 to 100 inch-pounds and lockwire. (QA) 4-98. ACCESSORY GEARBOX PRESSURE OIL TUBE. 4-99. REMOVAL. (Figure 4-24.) a. Disconnect tube (15) from tee (13). b. Remove two bolts (14) securing tee (13) to gearbox. c. At upper end of tube (10), remove two bolts (19) securing fitting to accessory gearbox. Remove tube (10). 4-100. INSTALLATION. (Figure 4-24.)

Lubricating Oil 1 a. Install new gasket (20) and packing (21) on tube (10). Lightly lubricate packing with engine oil, MIL-PRF-23699. b. Install new gasket (12) and packing (11) on tee (13). Lubricate packing with engine oil, MIL-PRF-23699. c. Install tube (10) on accessory gearbox and secure tee (13) with two bolts (14) and tube fitting with two bolts (19). Torque bolts 25 to 35 inch-pounds and lockwire. (QA) d. Connect tube (15) to tee (13). Torque connection 90 to 100 inch-pounds and Iockwire. (QA)


4-80

Figure 4-24. Pressure Oil Sense Line to Check and Relief Valve


Change 4 4-81

4-101. PRESSURE OIL TUBE TO OIL-TO-FUEL HEATER. 4-102. REMOVAL. (Figure 4-24.) a. Remove bolt (3) and nut (5) securing clamp (4) to bracket on accessory gearbox. Remove clamp. b. Remove bolt (9) and nut (6) securing clamp (7) to bracket (8). Remove clamp. c. Disconnect tube (2) at oil-to-fuel heater elbow (1) end elbow (16). Remove tube (2). 4-103. INSTALLATION. (Figure 4-24.) a. Connect tube (2) to elbow (1) and elbow (16). Torque connections 90 to 100 inch-pounds and lockwire. (QA) b. Install clamp (7) on tube (2) and secure to bracket (8) with bolt (9) and nut (6). Torque nut 36 to 40 inch-pounds. (QA) c. Install clamp (4) on tube (2) and secure to bracket with bolt (3) and nut (5). Torque nut 36 to 40 inch-pounds. (QA) 4-104. Pg SENSE TUBE FROM AFCU TO REDUCTION GEARBOX. 4-105. REMOVAL. (Figure 4-25.) a. Remove bolt (46) and nut (44) securing clamp (45) to bracket (43). b. Disconnect tube (47) at torque control unit and adapter (41). Remove tube. c. Disconnect tube (42) at power turbine governor and adapter (41). Remove tube. d. Disconnect tube (40) at adapter (41) and adapter (38). Remove tube. e. Remove bolt (33) and nut (36) securing clamp (34) to bracket (35). Remove clamp. f. Disconnect tube (37) at adapter (38) and connection to tube (23) at center fireseal. Remove tube.

g. Remove four screws (13), washers (7) and nuts (6) securing connector (12) to flange G fireseal. h. Remove bolt (31) and nut (29) securing clamp (28) to bracket (32). Remove clamp. i. Remove bolt (14) and nut (16) securing clamp (15) to bracket (17). Remove clamp. j. Remove bolt (11) and nut (9) securing clamp (10) to bracket (8). Remove clamp. k. Remove two bolts (24) and nuts (30) securing plate (25), seal (26), plate (27) and bracket (32) to center fireseal. l. Remove two bolts (18), washers (5) and nuts (4) securing plate (19) and seal (20) to flange G fireseal. m. Disconnect tube (23) from tube (3). Withdraw tube (23) from power section and remove plates and seals from tube (23). n. Remove nut (2) securing clamps (21) to gearbox, and remove clamp. o. Remove two nuts (1) securing clamps (22) to gearbox, and remove clamps. p. Disconnect tube (3) from AFCU and remove tube. 4-106. INSTALLATION. (Figure 4-25.) a. Connect tube (3) to AFCU. Torque connections 90 to 100 inch-pounds and Iockwire. (QA) b. Install two clamps (22) on tube (3) and secure to gearbox with nut (1). Torque nut 25 to 35 inch-pounds. (QA) c. Install clamp (21) on tube (3) and secure to gearbox with nut (2). Torque nut 25 to 35 inch-pounds. (QA)


4-82

Figure 4-25. Pneumatic Sense Lines – AFCU to Reduction Gearbox (Sheet 1 of 2)


Change 4 4-83

Figure 4-25. Pneumatic Sense Lines – AFCU to Reduction Gearbox (Sheet 2)

d. Perform resistance check of heater element to assure 15 to 25 ohms. e. Install plate (19, figure 4-25) and seal (20) on end of tube (23) with plate (25), seal (26) and plate (27) on other end of tube. f. Insert tube (23) through center fireseal and flange G fireseal. Connect end of tube to tube (3). Torque connection 90 to 100 inch-pounds and lockwire. (QA) g. Secure plate (19) and seal (20) to front fireseal with two bolts (18), washers (5) and nuts (4). Install nuts to firm contact plus 1/2 turn. (QA). h. Secure plate (25), seal (26), plate (27) and bracket (32) to center fireseal with two bolts (24) and nuts (30). Install nuts to firm contact plus 1/2 turn. (QA) i. Install clamp (28) on tube (23) and secure to bracket (32) with bolt (31) and nut (29). Torque nut 25 to 35 inch-pounds. (QA) j. Secure electrical connector (12) to front fireseal with four screws (13), washers (7) and nuts (6). Torque nuts 6 to 8 inch-pounds. (QA)

k. Install clamp (15) on electrical pigtail and secure to bracket (17) with bolt (14) and nut (16). Torque nut 25 to 35 inch-pounds. (QA)

Sealing Compound 8 I. Install clamp (10) on electrical pigtail and secure to bracket (8) with bolt (11) and nut (9). Torque nut 25 to 35 inch-pounds. Seal junction of pigtail to heating element with sealing compound, AMS-S-8802. (QA) m. Connect tube (37) to tube (23) and adapter (38). Torque connections 90 to 100 inch-pounds and Iockwire. (QA) n. Install clamp (34) on tube (37) and secure to bracket (35) with bolt (33) and nut (36). Torque nut 25 to 35 inch-pounds. (QA) o. Connect tube (40) to adapter (38) and adapter (41). Torque connections 90 to 100 inch-pounds and lockwire. (QA) p. Connect tube (42) to power turbine governor and adapter (41). Torque connections 90 to 100 inch-pounds and lockwire. (QA)


4-84 Change 5

q. Connect tube (47, figure 4-25) to torque control unit and adapter (41). Torque connections 90 to 100 inch-pounds and lockwire. (QA) r. Install clamp (45) on tube (47) and secure to bracket (43) with bolt (46) and nut (44). Torque nut 25 to 35 inch-pounds. (QA) s. Carry out following pressure test: 1. Disconnect Pg air supply tube connec-tion at front fireseal (figure 4-25). Blank off exposed end of tube not being tested using suitable cap.

WARNING

High pressures used during testing may cause rupturing or bursting of faulty tubes and hoses. The result could be serious injury. To prevent injury, cover all tubes and hoses with a suitable safety shield during testing. When caps or plugs are used, assure they are securely installed to prevent them from being blown out. Assure that pressures are bled off before exposing or touching hoses or tubes.

2. Connect a supply of clean, dry air at 75 to 85 psi to exposed Pg delivery tube connection.

Leak Detection Compound 20 3. Apply Leak Tec 372 (CAGE 03530) fluid or equivalent to entire surface of all connecting points throughout the Pg pressure system under test. No leaks are permitted except from power turbine governor, torque control unit and automatic fuel control system pneumatic bleed. 4. Should no leaks be found, wipe all leak-checking fluid from connections. Carry out steps 1. through 3. if required, on untested section of Pg tube system. 5. If leaks are found, the part or connection shall be examined for defects and

retorqued. A final test shall be carried out. Refer to step 1., preceding. 6. Disconnect air supply, remove blanking plug and reconnect Pg air supply. 4-107. INSULATED AND HEATED TUBES. 4-108. Check rubber sheath and boots of insulated and heated tubes for deterioration, breakdown of bonding with tube and cuts. Repair up to 3 inches long in rubber sheath per paragraph 4-109. Replace sheaths and boots which are unacceptable per paragraph 4-110. Refer to figure 4-26. 4-109. MINOR REPAIR - INSULATED AND HEATED TUBES. Repair cuts of less than 3 inches long in rubber sheath as follows:

Acetone 9 a. Clean and degrease metal and rubber surfaces using acetone, ASTM D329.

Silicone Rubber Adhesive 10 b. Apply adhesive, MIL-A-46106, or equiva-lent, on surface to a uniform thickness of 0.010 to 0.030 inch. Establish uniform contact between surfaces and apply sufficient pressure to displace sealant. If cut is large, bind area lightly with plastic covered wire until sealant has cured. c. Allow sealant to cure 24 hours at room temperature. d. Remove plastic covered wire, if fitted, trim and clean off surplus sealant using acetone, ASTM D329.


Change 4 4-85

Figure 4-26. Heated Pneumatic Tube Electrical Connector and Protective Boot

4-110. RUBBER SHEATH REPLACEMENT – INSULATED AND HEATED TUBES. Install new rubber sheath on insulated and heated tube as follows: a. Remove damaged sheath by cutting, taking care not to damage rubber boot or insulation. b. Cut a length of 1 inch diameter heat shrink sheathing (silicone rubber RT-876) approximately 1 inch longer than length of tubing to be covered. There shall be a 3/8-inch overlap at junction with rubber boot. c. Carefully ease replacement sheathing over tube and insulation until end abuts electrical lead.

CAUTION

Take care in the area adjacent to the boot; the boot has been previously heatshrunk and further heating could cause damage.

d. Use a hot air blower at 350° to 400°F (177° to 204°C) to heat replacement sheathing evenly all over. e. As sheathing starts to contract, massage by hand to obtain a uniform fit.

Silicone Rubber Adhesive 10 f. At completion of heat shrinkage and massage treatment, trim off excess sheathing and seal open end with Silastic adhesive, MIL-A-46106. g. Carry out electrical circuit check as detailed in paragraph 4-111. 4-111. TESTING. Use an ohmmeter to check electrical resistance of heated tube. Connect meter leads across the two connector pins. Resistance shall be 15 to 25 ohms. 4-112. FUEL TRANSFER TUBES. 4-113. REMOVAL. (Figure 4-27.) a. Remove bolts (7) and nuts (9) securing double clamp (8) to bracket (10).


4-86 Change 4

b. Remove bolt (2, figure 4-27) and nut (6) securing double clamp (4) to bracket (3). c. Remove bolt (13) and nut (17) securing clamp (16) to bracket (12), remove clamp (16) from fuel transfer tube (11). d. Remove two bolts (14), washers (22) and nuts (21), securing plate (18), insulation (19), seal (20) and bracket (12) to flange G fireseal. e. Disconnect tube (23) from tube (11) at center fireseal. f. Remove nut (15) securing tube (11) to center fireseal. g. Disconnect coupling (1) at MFCU. h. Remove plate (18), insulation (19) and seal (20) from tube (11) and withdraw tube (11) from power section. i. Remove bolt (26) and nut (24) securing clamp (25) to bracket (27). Remove clamp from tube (23). j. Disconnect tube (23) at adapter (28) and remove tube (23). k. Disconnect tube (30) or fIowmeter (31) at adapter (34) and remove tube (30) or flowmeter (31). Remove adapter (28) from tube (30) or flowmeter (31). I. Disconnect tube (33) from fuel flow divider and tube (38). Remove tube (33). m. Remove bolt (37) and nut (35) securing clamp (36) to bracket (45) and remove clamp. n. Disconnect tube (38) from surge dampener (39) and remove tube. 4-114. INSTALLATION. (Figure 4-27.) a. Install clamp (36) on fuel transfer tube (38). b. Connect tube (38) to surge dampener (39). Install clamp (36) on tube (38) and attach to bracket (45) with bolt (37) and nut (35). Do not torque at this stage.

c. Align center connection tube (38) and install tube (33) to fuel flow divider and center connection of tube (38). Torque connection 90 to 100 inch-pounds and lockwire. (QA) d. Secure previously installed clamp (36) to bracket with bolt (37) and nut (35). Torque nut 25 to 35 inch-pounds. (QA) e. Install adapter (34) on tube (38). Torque connection 90 to 100 inch-pounds and lockwire. (QA)

Calibration Fluid 3

Aviation Turbine Fuel 2 f. Install new packing (32) on adapter (34). Lightly lubricate packing with calibration fluid, MIL-PRF-7024, Type II, or clean JP 4/5 fuel. g. Connect tube (30) or flowmeter (31) to adapter (34). Torque connection 90 to 100 inch-pounds and lockwire. (QA) h. Lightly lubricate new packing (29) with calibration fluid, MIL-PRF-7024, Type Il, or clean JP 4/5 fuel. Install new packing (29) on adapter (28) and install adapter on tube (30) or flowmeter (31). Torque connection 90 to 100 inch-pounds and lockwire. (QA) i. Insert end of tube (11) through flange G fireseal and install seal (20), plate (18) and two insulations (19) on tube inserted through fireseal. j. Connect tube (11) to MFCU connection (1). Torque connection 90 to 100 inch-pounds and Iockwire. (QA)


Change 5 4-87

k. Secure tube (11, figure 4-27) to center fireseal with nut (15). Torque nut 90 to 100 inch-pounds. (QA) l. Connect tube (23) to end of tube (11) and adapter (28). Torque connections 90 to 100 inch- pounds and Iockwire. (QA) m. Install clamp (25) on tube (23) and secure to bracket (27) with bolt (26) and nut (24). Torque nut 25 to 30 inch-pounds. (QA) n. Secure bracket (12), plate (18), insulations (19) and seal (20) to flange G fireseal with two bolts (14), washers and nuts (21). Install nuts to firm contact plus 1/2 turn. (QA) o. Install double clamp (4) on tube (11) and P3 pressure tube, and secure to bracket (10) with bolt (7) and nut (6). Torque nut 25 to 30 inch-pounds. (QA) p. Install double clamp (8) on tube (11) and P3 pressure tube, and secure to bracket with bolt and nut. Torque nut 25 to 30 inch-pounds. (QA) 4-115. FUEL SURGE DAMPENER. The fuel surge dampeners are situated in the fuel supply line on each power section at approximately the 7 o'clock position. 4-116. REMOVAL. (Figure 4-27.)

Aviation Turbine Fuel 2 a. Disconnect fuel surge dampener (39) connection from fuel line (38). b. Remove nut (41) and bolt (43) securing clamp (42) to bracket (44).

4-117. DISASSEMBLY. (Figure 4-28.) a. Remove Iockwire and four bolts (1) and adapter (2) from housing (9). b. Withdraw dampener (6), spring (7) and spacers (8) from housing (9). 4-118. INSPECTION AND CLEANING.

Dry Cleaning Solvent 7

Compressed Air 19 a. Clean components of surge dampener with cleaner, MIL-PRF-680, Type II, and using a soft bristle brush if necessary. Dry parts with clean dry air. b. Inspect components for nicks, scoring and corrosion, blend out any nicks or scoring defects using a stone Grade AF-3-J-B or equivalent. c. Assure dampener (6) slides freely in bore of housing (9). 4-119. ASSEMBLY. (Figure 4-28.) a. Insert spacers (8) and spring (7) into housing (9).


4-88

Figure 4-27. Fuel Transfer Tubes (Sheet 1 of 2)


4-89

Figure 4-27. Fuel Transfer Tubes (Sheet 2)


4-90 Change 4

Figure 4-28. Fuel Surge Dampener

Calibration Fluid 3

Aviation Turbine Fuel 2 b. Lubricate two preformed packings (5, figure 4-28) and vee packing (4) with calibration fluid, MIL-C-7024, Type II, or clean JP 4/5 fuel, and install on dampener (6). c. Install dampener in housing (9), assure it moves freely against spring (7). d. Install preformed packing (3) on adapter (2) and secure to housing (9) with four bolts (1). Torque bolts 32 to 36 inch-pounds and lockwire. (QA)

4-120. INSTALLATION. (Figure 4-28.) a. Install clamp (42) on surge dampener (39) and secure to bracket (44) with nut (41) and bolt (43). Torque nut 36 to 40 inch-pounds. (QA) b. Connect fuel line (38) to fuel surge dampener (39). Torque connection 90 to 100 inch-pounds and lockwire. (QA) 4-121. FUEL SURGE ACCUMULATOR. The fuel surge accumulators are installed on T400-CP-400 power sections Serial No. 64576 and subsequent. The accumulators are situated in the fuel supply line on each power section at approximately the 7 o'clock position. 4-122. REMOVAL. (Figure 4-27.) a. Disconnect accumulator (40) from transfer tube (38). b. Remove nut and bolt securing clamp (42) to bracket (44) and remove accumulator (40). c. Remove clamp (41) from accumulator.


Change 5 4-91

4-123. INSPECTION AND CLEANING.

Dry Cleaning Solvent 7

Compressed Air 19 a. Clean components of surge dampener with cleaner, MIL-PRF-680, Type II, and using a soft bristle brush if necessary. Dry parts with clean dry air. b. Inspect components for nicks, scoring and corrosion, blend out any nicks or scoring defects using a stone Grade AF-3-J-B or equivalent. 4-124. INSTALLATION. (Figure 4-27.) a. Install clamp (42) on accumulator (40). b. Install accumulator (40) on power section. Secure clamp (42) to bracket (44) with bolt (43) and nut (41). Torque nut to 36 to 40 inch-pounds. (QA) c. Connect accumulator to transfer tube (38). Torque connection 90 to 100 inch-pounds and lockwire. (QA) 4-125. ITT LIMITER SYSTEM. The ITT trim bias unit provides ITT trim bias and contains circuitry to function in conjunction with the solenoid valve as a ITT limiter although the limiting function has been deactivated.

4-126. ITT TRIM BIAS UNIT. The ITT trim bias units are mounted on outboard side of the engine reduction gearbox. 4-127. REMOVAL. (Figure 4-29.) a. Disconnect harness (8) and power supply cable from connectors on lower side of ITT trim bias unit (15). b. Remove four bolts (16) and nuts (14) securing ITT trim bias unit (15) to bracket on reduction gearbox. Remove ITT trim bias unit. 4-128. INSTALLATION. (Figure 4-29.) a. Position ITT trim bias unit (15) with single connector up, on reduction gearbox bracket and install four bolts (16) and secure with nuts (14). Torque nuts 32 to 36 inch-pounds. (QA) b. Connect harness (8) to lower aft connector, and power input cable to lower forward connector. Install connectors fingertight and Iockwire. (QA) c. Perform trim check and adjustment. 4-129. SENSING AND TRIM CABLES TO ITT LIMITER UNIT. 4-130. REMOVAL. (Pre-PPC No. 76.)

NOTE

This procedure applies to power sections incorporating PPC No. 51 or Serial No. 64695 and subsequent.

a. Remove nuts (2 and 3, figure 4-29) securing thermocouple leads to terminal block. b. Remove three nuts (7), bolts (5) and bracket (6).


4-92

Figure 4-29. ITT Thermocouple Harness (Pre-PPC 76)


Change 3 4-93

CAUTION

Do not attempt to disassemble connection from plate (12, figure 4-29).

c. Remove four nuts (13) and screws (11) securing plate (12) to rear bulkhead. d. Withdraw ITT harness (8) through rear bulkhead. e. Unscrew ITT harness connection from ITT limiter and remove harness. 4-131. REMOVAL. (Post PPC No. 76 and ECP T400-8.) a. Remove two bolts (8, figure 4-30) and shield (10). b. Remove nuts (2 and 7), disconnect jumper leads (3 and 4) from terminal block. c. Remove nuts (12 and 19), disconnect and remove jumper leads (3 and 4), wiring harness (1), and airframe wiring harness (not shown) from off mount terminal block.

NOTE

Further disassembly of nuts, bolts and insulations from stud support bracket is unnecessary unless damage is evident.

d. Remove two nuts securing bracket (5) to C flange. Remove bracket as an assembly. Replace defective parts as required. e. Remove three nuts (7, figure 4-29), bolts (5), and bracket (6).

CAUTION

Do not attempt to disassemble connection from plate (12).

f. Remove four nuts (13) and screws (11) securing plate (12) to rear bulkhead. g. Unscrew ITT harness connection from ITT limiter and remove harness. 4-132. INSTALLATION. (Pre-PPC No. 76.) a. Insert thermocouple harness (8, figure 4-29) through flange A fireseal from reduction gearbox side.

b. Connect sensing harness (8) connector to ITT trim bias unit (15). Install connection fingertight and Iockwire. (QA) c. Secure harness adapter to flange A fireseal with four screws (11) and nuts (13). Torque nuts 6 to 8 inch-pounds. (QA) d. Install clamp (4) on harness (8) and secure to clamp (10) with nut (7) and bolt (5). Torque nut 25 to 35 inch-pounds. (QA) e. Install clamp (4) on harness (8) and secure to clamp (9) with bolt (5) and nut (7). Torque nut to 25 to 35 inch-pounds. (QA) f. Install clamp (4) on harness (8) and secure to bracket (6) with bolt (5) and nut (7). Torque nut 25 to 35 inch-pounds. (QA)

CAUTION

Assure helicopter wiring harness terminals do not contact any portion of power section ITT lug shield or gas generator case after retaining nuts are torque.

g. Secure thermocouple leads to terminal block (1) with nuts (2 and 3). Torque nut (2) 8 to 12 inch-pounds and nut (3) 10 to 15 inch-pounds. (QA) 4-133. INSTALLATION. (Post PPC No. 76 and ECP T400-8.) a. Install harness as detailed in paragraph 4-132, subparagraphs a. through f. b. If terminal stud support bracket has been disassembled, proceed as follows: 1. Install bushings (15 and 17, figure 4-30) up through appropriate holes in bracket (5). 2. Install insulating pad (14) on top face of bracket (5), locating holes on bushings (15 and 17). 3. Install studs (13 and 20) through from top of bracket, locating flats against butt of pad (14). Secure to underside of bracket with nuts (16 and 18). Torque nut (16) 8 to 12 inch-pounds and nut (18) 10 to 15 inch-pounds. (QA)


4-94 Change 3

Figure 4-30. ITT Thermocouple Harness (Post PPC 76 and ECP T400-8)


Change 5 4-94A/(4-94B blank)

c. Install assembled bracket (5, figure 4-30) on C-flange, and secure with two nuts (21). Torque nuts 32 to 36 inch-pounds. (QA) d. Install airframe wiring harness (not shown), jumper leads (3 and 4), and wiring harness (1) to correct studs (13 and 20). Secure with nuts (12 and 19). Torque nut (12) 8 to 12 inch-pounds and nut (19) 10 to 15 inch-pounds. (QA) e. Install terminals of jumper leads (3 and 4) on appropriate posts of terminal block and secure with nuts (2 and 7). Torque nut (2) 8 to 12 inch-pounds and nut (7) 10 to 15 inch-pounds. f. Secure shield to gas generator case with 2 bolts (8). Tighten bolts torque 25 to 35 inch-pounds and lockwire. (QA)

4-134. REPAIR OF CRACKED CERAMIC ITT TERMINAL BLOCK.

Synthetic Ceramic Binder and Filler 21 a. Secure loose terminals or replace missing ceramic insulation using ceramic binder Sauereisen No. 29 (CAGE 80703) or equivalent. b. Prepare a mixture of ceramic filler and ceramic binder Sauereisen No. 29 in accordance with manufacturer's instructions.


Change 5 4-95

Synthetic Ceramic Binder and Filler 21 c. Assure that all surfaces coming into contact with the filler are free from grease and dirt. Contamination by these impurities will adversely affect the physical and electrical insulating properties of the cement. d. Secure loose terminals by applying sealant of ceramic binder as needed around the terminals in the block.

WARNING

Gases that are confined, or flammable liquids that vaporize in a heated oven, are hazardous. The design and construction of the heat-soak facilities shall comply with all applicable statutory codes and regulations.

e. The terminal block is to be heat dried at 150°F (66°C) for 3 hours to assure complete setting and drying. As an alternate, dry at room temperature for 2 hours and afterwards run the engine for 10 minutes to generate heat to speed up the drying process. f. When replacing missing ceramic insulation, apply the cement as required. Cure the assembly in the manner prescribed in step e. above. This includes the alternate method. g. Perform insulation resistance and loop resistance check. 4-135. POWER LEVER (Ng) CONTROLS. 4-136. REMOVAL. a. Remove cabin center deck panels, trans-mission pylon side panels, air inlet fairings and inspection panel as required for access to

components to be removed. Refer to NAVAIR 01-110HCE-2-2 and paragraph 4-158. b. Remove control tubes (1, 2, 3 and 4, figure 4-31) by removing cotter pins (5), nuts (6), washers (7) and bolts (8). Loosen clamps (9) on boots around control tubes (2). Remove required control tubes from structure. c. Remove bellcranks (10 and 11) from bulkhead by removing cotter pins (12), nuts (13), washers (14) and bolts (15). d. Remove jackshaft (16) by removing three screws (17), washers (18) and one mount (19) on left side and four nuts (20), washers (21), screws (22) and one bearing (23) on right side. Remove cotter pins (24), nut (25), washers (26) and mount (19) from end of jackshaft. e. Remove clamps (1, figure 4-32) around boots (2 and 3) and slide boots clear of bulkhead collar. Slide retainer (4) clear of boot and remove snap-ring (5) from retainer. Slide bushing (6) clear and remove. Leave boot and retainer on tube until tube is removed. f. Remove control tubes (7 and 8) and link (40) by removing cotter pins (9), nuts (10), washers (11) and bolts (12) at each end. Lift required control tube from structure. g. Remove middle left jackshaft (13) by removing cotter pin (14), nut (15) and washer (16) from left end, also screws (17) and washers (18) securing mounts (19) to structure. h. Remove middle right bellcrank (20) by removing cotter pins (21), nut (22), washer (23) and bolt (24), also screws (25) and washers (26) securing mount (27) to structure. i. Remove upper left jackshaft (28) by removing cotter pins (29), nut (30) and washer (31) from left end, also screws (32), washers (33) and nuts (34) securing mounts (35) to structure. Note locations of screws for installation. j. Remove torque tubes (36) by removing screws (37) and washers (38) securing pillow blocks (39) and lift units from structure.


4-96

Figure 4-31. Power Level Controls – Lower Section


4-97

Figure 4-32. Power Lever Controls - Upper Section


4-98 Change 3

4-137. INSPECTION. a. Inspect rod ends, bearings and clevis ends within limits in figure 4-33. b. Inspect for bent control tubes, loose nuts and bolts, missing cotter pins and other possible causes of rubbing and wear. Torque nuts and bolts if necessary. Replace any missing cotter pins. c. Inspect for proper length adjustment of control tubes (10, 11, 15 and 30, figure 4-34). Adjust if necessary. d. Refer to NAVAIR 01-110HCE-2-5 for control tube wear limits. e. Replace faulty items. 4-138. INSTALLATION. a. Install torque tubes (36, figure 4-32) on left and right engine decks with screws (37) and washers (38) holding pillow blocks (39) to deck. b. Install upper left jackshaft (28) on mounts (35) with washer (31), nut (30) and cotter pin (29) on left end. Install mounts with screws (32), washers (33) and nuts (34). c. Install middle right bellcrank (20) on mount (27) with bolt (24), washer (23), nut (22) and cotter pin (21). Install mount on structure with washers (26) and screws (25). d. Install middle left jackshaft (13) on mounts (19) with washer (16), nut (15) and cotter pin (14) on left end. Install mounts on structure with washers (18) and screws (17). e. Install boots (2 and 3) retainers (4) on control tubes (7 and 8). Install control tubes (7 and 8) and link (40) with bolts (12), washers (11), nuts (10) and cotter pins (9) on each end. f. Slide bushing (6) into retainers and secure in place with snap-rings (5). Slide retainer into boots and install boots onto bulkhead collars. Install

clamps (1) over ends of boots. Ensure retainers and clamps are flush with the edge of the boots. g. Install mount (19, figure 4-31) on left end of jackshaft (16) with washers (26), nut (25) and cotter pin (24). Slide bearing (23) on right end. Position unit in structure and install three washers (18) and screws (17) on left end and four screws (22), washers (21) and nuts (20) on right end. h. Install bellcranks (10 and 11) in bulkhead mounts with bolts (15), washers (14), nuts (13) and cotter pins (12). i. Install control tubes (1, 2, 3 and 4) in system with bolts (8), washers (7), nut (6) and cotter pins (5). Secure boots around control tubes (2) with clamps (9). j. Install access panels, doors and cowling removed for access. Refer to NAVAIR 01-110HCE-2-2 and paragraph 4-159. 4-139. IDLE STOP SOLENOIDS. Two solenoids (24 and 34, figure 4-34) are located on the engine deck at left and right sides near the cabin aft bulkhead. Each solenoid is mounted in a bracket with slotted screw holes, for adjustment on a serrated base to maintain proper clearance with a stop arm on the control linkage torque tube. 4-140. REMOVAL. a. Open engine lower cowl door for access. Refer to paragraph 4-152. b. Disconnect electrical wires from terminals of solenoid (5, figure 4-35). Remove diode (9) from terminals and retain for reinstallation. c. Remove four screws (1) and washers to detach solenoid (5), and bracket (2), base (3) and spacers (4) from engine deck. d. Remove four screws (7) to separate solenoid and shims (6) from bracket (2).


4-99

Figure 4-33. Power Lever Control Wear Limits (Sheet 1 of 2)


4-100 Change 4

Figure 4-33. Power Level Control Wear Limits (Sheet 2)


4-101

Figure 4-34. Power Level (Ng) Controls


4-102 Change 6

Figure 4-35. Idle Stop Solenoid Installation

4-141. INSTALLATION.

CAUTION

During alignment/adjustment it is possible to bind plunger/shear stop at mounting pad.

a. Assemble solenoid (5, figure 4-35) to bracket (2) with screws (7) using laminated shims (6) under solenoid as required to align plunger for free movement through bushing of bracket. b. Assemble solenoid and bracket on base (3) and spacers (4). Ensure washers (10) are installed between spacer and engine deck. Secure with screws (1) and washers (1A) to mounting holes in engine deck. c. Connect electrical wires to terminals of solenoid. Install diode (9) across terminals of

solenoid placing positive lead on terminal wired to ground (REF NAVAIR 01-110HCE-2-13) and tighten Iocknuts. d. Electrically retract solenoid plunger by use of IDLE STOP REL switch, and check for 0.003 to 0.015 inch clearance between plunger and face of stop (8). Adjust position of solenoid bracket on base to obtain correct clearance, and torque screws evenly. (QA) e. Close engine cowling. Refer to paragraph 4-152. 4-142. IDLE STOP ASSEMBLY. 4-143. REMOVAL. a. Locate left power lever control torque tube, 212-060-737-5, on left side of engine service deck.


4-103

b. Center punch and drill monel rivet. Use No. 40 drill for approximately 1/8 inch, then use No. 11 drill and remove head of rivet. Use small drift punch, and, with the inboard side of torque tube lever supported with bucking bar or equivalent, tap rivet out of stop and lever. c. Remove outer jamnut from adjusting screw and remove stop. Do not disturb inner nut. 4-144. INSTALLATION. a. Position idle stop on adjusting screw (with tang of idle stop outboard). b. Align hole in stop with hole in lever on torque tube and install rivet, MS20427M6C12. Check frequently during rivet installation to assure that idle stop moves freely after rivet is installed. 4-145. DROOP COMPENSATOR (Nf) CONTROLS. 4-146. REMOVAL. (Figure 4-36.) a. Open engine lower left cowl door, remove left and right twin gearbox side cowlings, panels under fuselage and cabin center deck panels to gain access to components to be removed. b. Remove clamps (26) and slide boot (25) on tube away from bulkhead. Slide retainer (23) clear of boot and remove snap-ring (22) from retainer. Slide bushing (24) clear and remove. Leave boot and retainer on component until component is removed. c. Remove control tubes (1, 3, 5, 12 and 15) and actuator (9) from system by removing cotter pins (21), nuts (20), washers (19) and bolts (18) at each end and remove desired component from structure. Disconnect electrical actuator wires. d. Remove bolts (18) and washers (19) and mounts (27) under engine reduction gearbox. Remove jackshaft (11) and remove nut (20) and

washer (19) from left end. Slip mounts (27) from each end of jackshaft. e. Remove bolts and washers from idler (2) or bellcrank (4) mount as required for removal. Remove cotter pin, nut and washer retaining idler or bellcrank to mount. 4-147. CAMBOX ASSEMBLY. The droop com-pensator cambox assembly (8, figure 4-36) is mounted on the engine deck outboard of the left engine power section at Station 188. 4-148. REMOVAL. a. Open engine lower cowl door at left side. Refer to paragraph 4-152. b. Disconnect actuator (9, figure 4-36) and control tube (5) from slider and bellcrank of cambox (8) by removing attaching bolts. Tag wires to identify. c. Remove bolt (3, figure 4-37) nut and washers to detach aft end of housing (4) from mount (5). d. Remove cotter pin (6), nut (7) and washer (9) from inboard end of bolt (8), and remove cambox and slider housing assembly from mount. e. Withdraw bolt (8) and washer from housing and bellcrank (12). Keep shims (10) for assembly. f. Pull cam and slider assembly free of housing. g. Remove pin (19) to separate slider (13) and bearing (20) from cam. h. When necessary, remove nut (14), serrated lockwasher (15), bolt (17) and washer (16) from arm of bellcrank (11) and adjustment slot of cam (12). Bellcrank and cam will remain together, attached by rivet (18). i. Remove four screws (2) and washers to detach mount (5) from engine deck.


4-104

Figure 4-36. Droop Compensator Components


4-105

Figure 4-37. Droop Compensator Cambox Assembly

4-149. INSPECTION - DROOP COMPENSATOR CONTROL. a. Inspect critical rodends, bearings and clevis ends within limits in figure 4-38. b. Inspect control tubes within limits in NAVAIR 01-110HCE-2-5. c. Replace faulty items in accordance with applicable paragraph in NAVAIR 01-110HCE-2-5. d. Bellcrank Shear Section. Bellcrank (5, figure 4-39) is made up of two arms (1 and 2,

figure 4-40) riveted together to form a 90 degree angle. The MS20470B3 rivet (3, figure 4-40) is designed to shear if jamming occurs in the droop compensator controls, thus permitting emergency use of the collective controls. If rivet is shorn, bellcrank must be removed and replaced. 1. Removal - Bellcrank. (a) Bellcrank is located under engine deck. (b) Disconnect control tubes (4 and 6, figure 4-39).


4-106 Change 2

(c) Remove cotter pin, nut and washer and remove bellcrank (5, figure 4-39). 2. Repair or Replacement - Bellcrank. (a) Remove old rivet. (b) Check arms (1 and 2, figure 4-40) for freedom of movement on bearing. (c) Install MS2047OB3 rivet in arms (1) and (2). 3. Installation - Bellcrank. (a) Install bellcrank (5, figure 4-39) on mount and install nut, washer and cotter pin. (b) Connect control tubes (4) and (6). 4-150. INSTALLATION - CAMBOX ASSEMBLY. a. Align arm of bellcrank (11, figure 4-37) to adjustment slot of cam (12). Insert bolt (17), with washer (16) under head, from bellcrank side. Place serrated Iockwasher (15) on bolt next to cam. Install nut, torque 20 to 25 inch-pounds. (QA) b. Place bearing (20) in cam slot, align end of slider (13) over bearing, and insert pin (19) through slider and bearing. c. Insert free end of slider into front end of housing. Slide cam and slider aft until pin (19) is covered. Align bellcrank bearing in fork of housing and insert bolt (8) with washer (9) under head. Check gap between bearing inner race and housing, and install laminated shims to maximum of four to obtain 0.001 to 0.003 inch clearance with no torque on bolt. d. Position mount (5), flat side outboard, to engine deck mounting holes and install four screws (2) with washers. e. Position cambox housing with bolt (8) inserted through forward leg of mount, and secure with washer (9) and nut (7). Align housing to rear leg of mount and install bolt (3), with

washers under head and nut, torque 20 to 24 inch-pounds. Torque nut (7) 12 to 15 inch-pounds and install cotter pin (6). (QA) f. Connect actuator (10, figure 4-39) to aft end of slider with bolt, washer and nut secured by cotter pin. Follow rigging procedure to adjust and connect control tube (6) to cambox bellcrank (reference NAVAlR 01-110HCE-2-3.1, Power Plant Ground Operation and Conditioning Manual). (QA) 4-151. INSTALLATION - DROOP COMPENSA-TOR CONTROL. (Figure 4-36.) a. Slide jackshaft mounts (27) on ends of jackshaft (11). Install washer (19) and nut (20) on left end. Position assembly under reduction gearbox and install jackshaft mounts (27) with washers (19) and bolts (18). Torque bolts 190 inch-pounds and Iockwire. (QA) b. Install idler (2) and bellcrank (4) on mount with washer (19), nut (20) and cotter pin (21). Install idler (2) and bellcrank (4) on structure with washer (19) and bolt (18). c. Position boots (25) and retainers (23) on proper component. Install control tubes (1, 3, 5, 12 and 15) and actuator (9) in structure with bolts (18), washers (19), nuts (20) and cotter pins (21). Connect actuator (reference NAVAlR 01-110HCE-2-11, Engine Controls and Wiring Schematic). d. Slide bushing (24) into retainer (23) and install snap-ring (22) to hold bushing in place. Slide boot (25) on bulkhead adapter and install clamp (26) on each end. 4-152. COWLING. Cowling sections are con-structed of aluminum alloy and cover the transmission, air management system, engine and oil coolers. 4-153. REMOVAL. a. Release latches (2, figure 4-41) at each aft corner and raise transmission fairing (1) on the forward hinge (3).


4-107

Figure 4-38. Droop Compensator Controls – Wear Limits


4-108

Figure 4-39. Droop Compensator (Nf) Controls


4-109

Figure 4-40. Droop Compensator –

Bellcrank Shear Section

NOTE

Some inlet fairings will be secured with bolts or screws instead of alignment pins.

b. Release latches (5, figure 4-41) on air inlet fairings (4). Lift up and forward to remove air inlet fairings from alignment dowels (6). c. Release latches (2, figure 4-42) and swing engine lower cowl (1) out and aft. Remove pins (8) on hinge arm at firewall and lift off engine lower cowl. Release latches (4) and open engine upper cowl. d. Disconnect starter-generator air tube under air screen (7) and loosen engine top cowl (5) fasteners (6). Remove engine top cowl (5) and engine upper cowl (3) as a unit. e. Press to release latches (1, figure 4-43) and raise oil cooler air scoop (2). Remove nuts (3), washers (4) and bolts (5) at hinges (6) and remove oil cooler air scoops. f. Remove screws (7) and lift off reduction gearbox side cowling (8). Remove screws (9) and remove reduction gearbox top cowlings (10).

g. Disconnect rotating beacon (11) electrical plug and remove four screws attaching reduction gearbox oil filler (15). Remove screws (12) and remove reduction gearbox top panel (13). Remove screws and oil cooler fairing (14). 4-154. INSTALLATION. a. Install oil cooler fairing (14, figure 4-43) with screws. Install reduction gearbox top panel (13) with screws (12). Connect rotating beacon (11) electrical plug and install screws on reduction gearbox oil filter (15). b. Install reduction gearbox top cowlings (10) with screws (9). Install reduction gearbox side cowlings (8) with screws (7). c. Install oil cooler air scoops (2) with bolts (5), washers (4) (three on each side of bearing) and nuts (3) through hinges (6); fasten latches.

CAUTION

Assure breather vents protrude through cowl to assure oil vapors are vented overboard.

d. Install top cowl (5, figure 4-42) and upper engine cowl (3) as a unit and secure in place with fasteners (6). Connect starter-generator air cooling tube under air screen (7). Leave upper engine cowl (3) open at this time. e. Close upper engine cowl (3) and fasten latches (4). Position hinge arm of lower engine cowl (1) in hinge area and install pins (8). Swing cowl in place and close latches (2).

NOTE


f. Align dowels on air inlet fairings (4, figure 4-41) as they are positioned on roof. Fasten latches (5). Lower transmission fairing (1) and close latches (2).


4-110

Figure 4-41. Cowling – Transmission and Air Inlet


4-111

Figure 4-42. Cowling – Power Plant


4-112

Figure 4-43. Cowling – Reduction Gearbox


4-113

4-155. ADJUSTMENT. a. Adjust the latches (2 and 5, figure 4-41) by adding or removing washers between the latch fitting and the cabin roof. With the fairings installed and latches closed, the latches are considered properly adjusted when the following conditions are met: 1. The fairings appear to be in the proper position relative to mating pieces. 2. The latch is observed through the hole in fairings (latch handle) to engage the latch fitting when the lower end of the latch handle is 2-1/4 to 1-3/4 inches from the fairing race. 3. The fairing is not loose when pushed by hand in the vertical and horizontal directions. b. Adjust the tongue latches (2 and 4, figure 4-42) on engine upper cowl (3) and engine lower cowl (1) by loosening the latch fitting screws, moving the latch fittings inboard or outboard, and torquing the screws. With the cowlings installed and latches closed, the latches are considered properly adjusted when the following conditions are met: 1. The cowls appear to be in the proper position relative to mating pieces. 2. With the latches closed, the latch tongue is observed to engage the latch fitting. Check the lower cowl closed with upper cowl open and upper cowl closed with lower cowl open. 3. The fairing is not loose when pushed by hand both inboard and outboard. c. Adjust the oil cooler air scoop (2, figure 4-43) and reduction gearbox side cowling (8) push button latches by replacing worn latches which engage the sheet metal frame with less than 3/16 inch tongue of latch.

4-156. AIR MANAGEMENT SYSTEM. 4-157. MAINTENANCE. Components of the air management system may be removed in any practical sequence for access, repair or replacement. Electrical circuits and components shall be maintained in accordance with NAVAIR 01-110HCE-2-10. Inspection doors are provided in the left and right induction baffles for the detection of foreign objects. 4-158. REMOVAL. (Figure 4-44.) a. Ejector. Remove top and side cowling. Disconnect drain line (7) from fitting on lower side of ejector (6). Remove bolts to detach ejector flange from firewall. Remove bolts to detach links (8) from oil cooler support at lower and outboard sides of ejector. Pull ejector assembly aft out of duct and firewall. Cover exhaust duct (5).

NOTE

Links (8) may be different lengths for bottom and side locations on ejector. If required when replacing links, use 1.26 inch center-to-center link.

b. Transition duct. Remove cowling for access. Disconnect hose (1, figure 4-45) from water wash ring. Remove bolts to detach duct (4, figure 4-44) from valve (3). Remove duct. c. Exhaust duct. Remove bolts around flange of duct (5). Remove duct. Cover engine opening. d. Valve. Disconnect electrical cable from connector on front of middle firewall. Remove screws to detach valve (3) from firewall. Remove valve assembly. e. Forward duct. Remove cowling over forward engine area. Remove screws attaching duct (1) to structure. Loosen or remove upper section of firewall as necessary to pull duct aft out of inlet fairing. f. Induction baffle. Release fasteners and remove screws to detach and remove panels of baffle (2).


4-114

Figure 4-44. Air Management System Installation (Sheet 1 of 2)


Change 6 4-115

Figure 4-44. Air Management System Installation (Sheet 2)

g. Protective cover plate (12, figure 4-44). Cut lockwire (15) so that plate drops from blanket. Remove remaining Iockwire. h. Ejector blanket (14). Cut Iockwire (13) lacing at top of blanket. Slide blanket off of ejector, being careful to not tear blanket corrugations on ejector link brackets (8). 4-159. INSTALLATION. (Figure 4-44.)

NOTE

The air management system is installed using an assortment of part number MS27039-1 cadmium plated and stainless steel screws. Part number MS27039-1 screws may be substituted with stainless steel AN3C bolts or equivalent.

a. Induction baffle. Assemble and attach panels of baffle (2) with fasteners and screws to each other and to firewalls.

b. Forward duct. Insert duct (1) into inlet fairing. Align aft end of firewall and install attaching screws. c. Valve. Connect electrical cable to actuator connector and with electrical power on move PART SET switch ON and OFF. Adjust actuator door to dimensions in figure 4-44. Position valve (3) against firewall and install attaching screws. d. Exhaust duct. Uncover mounting port on engine. Position duct (5) on engine exhaust flange. Install bolts with washers and nuts. e. Transition duct. Position duct (4) over exhaust duct. Align forward flanges on valve (3) and install attaching screws with washers. Connect hose (1, figure 4-45) to water wash ring.


4-116 Change 4

Figure 4-45. Engine Water Wash Provision

NOTE

Ejectors, 212-061-201-11/-12, have a titanium shell and therefore do not require the blanket (14) or the coverplate (12).

f. Ejector. Insert ejector (6, figure 4-44) through firewall, over exhaust duct (5) and into end of transition duct (4). Align each of links (8) to mounting bracket on oil cooler support, and install bolt with washers and nut. Attach ejector flange to firewall with screws and washers. Connect drain line (7) to fitting under ejector. g. Ejector blanket (14). Slide blanket around ejector, lining up holes in blanket with ejector

link brackets. Use care to not tear blanket on any sharp edges. Lace top posts together with Iockwire (13). h. Protective coverplate (12). Install with posts facing up against bottom of blanket (14) to prevent edge of cover plate from tearing blanket corrugations. Center plate so that one of 8.5 edges is against and centered on bottom exhaust ejector link (8). Plate should be laced with Iockwire (15) through holes of studs on plate and around blanket (14), and laced in with blanket lacing (13) on top. Assure that lacing (15) through stud holes is such that wire does not rub against plate edge. i. Install cowling.


Change 3 4-117

4-160. FIREWALLS. Three firewall assemblies are provided to isolate the engine intake section, the combustion section, the combining gearbox area and the main driveshaft tunnel. The firewalls, aft, middle and forward, are attached to the engine deck. 4-161. REMOVAL. a. Remove the engine air inlets. Refer to paragraph 4-152. b. Remove the engine cowling. Refer to paragraph 4-152. c. Remove the reduction gearbox cowling. Refer to paragraph 4-152. d. Remove the air management system. Refer to paragraph 4-158. e. Disconnect the fire extinguisher bottle; disconnect the fire extinguisher tubing and fire detector sensors as necessary for removal of firewalls. f. Remove lower section of center firewall. (See figure 4-46.) 1. Remove screws (1), washers (2), screws (3) and washers (4) securing right half of lower section of mid-firewall (5) to tunnel (6). 2. Remove screws (7) and washers (11) securing right half of lower section of mid-firewall (5) to deck (9). Remove section of firewall from helicopter. 3. Removes screws (10), washers (11), screws (12) and washers (13) securing left half of lower section of mid-firewall (14) to tunnel (6). 4. Remove screws (15) and washers (16) securing left half of lower section of mid-firewall (14) to deck (9). Remove section of firewall from helicopter. g. Remove tunnel. (See figure 4-46.)

1. Remove screws (17) and washers (18) securing end of tunnel (6) to lower section of aft firewall (19). 2. Remove screws (20) end washers (21) securing end of tunnel to lower section of forward firewall (22). 3. Remove screws (23) and washers (24) securing tunnel (6) to deck (9). 4. Remove tunnel from helicopter. h. Remove lower section of aft firewall. (See figure 4-46.) 1. Remove engine mounts (25). 2. Detach actuator (26). 3. Remove screws (27) and washers (28) securing lower section of aft firewall (19) to deck (9) and remove section from helicopter. i. Remove lower section of forward firewall. (See figure 4-46.) 1. Remove screws (29) and washers (30) securing lower section of forward firewall (22) to structure. 2. Remove screws (31) and washer (32) securing section of forward firewall to deck (9). 4-162. INSPECTION - LOWER AFT, LOWER MID AND LOWER FORWARD FIREWALL SECTIONS AND TUNNEL. (See figure 4-46.) a. Inspect firewall sections for damage, cracks, dents and scratches. b. Inspect tunnel for damage, dents, cracks and scratches. c. Inspect for missing nutplates.


4-118

Figure 4-46. Firewall Removal and Installation


Change 6 4-119

4-163. REPAIR – LOWER AFT, LOWER MID AND LOWER FORWARD FIREWALLS AND TUNNEL. Replace any damaged or missing nutplates. 4-164. INSTALLATION.

NOTE

The firewalls are installed using an assortment of part number MS27039-1 cadmium plated and stainless steel screws. Part number MS27039-1 screws may be substituted with stainless steel AN3C bolts or equivalent.

a. Install lower section of forward firewall (See figure 4-46.) 1. Position lower section of forward firewall (22) and secure to deck (9) with screws (31) and washers (32). 2. Secure firewall section to structure with screws (29) and washers (30). b. Install lower section of aft firewall. (See figure 4-46.) 1. Position lower section of aft firewall (19) and secure to deck (9) with screws (27) and washers (28). 2. Attach actuator (26). Refer to paragraph 4-145. 3. Install engine mounts (25). Refer to paragraph 4-176. c. Install tunnel. (See figure 4-46.) 1. Position tunnel (6) between forward and aft firewall sections (19 and 22). 2. Secure tunnel (6) to deck (9) with screws (23) and washers (24). 3. Secure forward end of tunnel (6) to lower section of forward firewall (22) with screws (20) and washers (24). 4. Secure aft end of tunnel (6) to lower section of firewall (19) with screws (17) and washers (18). d. Install lower section of mid-firewall. (See figure 4-46.)

1. Position left half lower section of mid-firewall (14) and secure to deck (9) with screws (15) and (16). 2. Install screws (10) and washers (11) to secure left half of lower section of mid-firewall to tunnel (6). 3. Position right half of lower section of mid-firewall (5) and secure to deck (9) with screws (7) and washers (8). 4. Install screws (3), washers (4), screws (1) and washers (2) to secure right half of lower section of mid-firewall (5) to tunnel (6). e. Connect the fire extinguisher bottle, fire extinguisher tubing and fire detector sensors. Refer to paragraph 4-180. f. Install the air management system. Refer to paragraph 4-159. g. Install the reduction gearbox cowling. Refer to paragraph 4-152. h. Install the engine cowling. Refer to paragraph 4-152. i. Install the engine air inlets. Refer to para-graph 4-152. 4-165. OIL COOLER SYSTEM. 4-166. MAINTENANCE. Oil lines, valves and fittings are standard aircraft parts, and can be replaced by normal practices. Drain oil before removing parts and perform servicing and check for leaks during ground run after replacement of parts. 4-167. REMOVAL - ENGINE OIL COOLERS. a. Open oil cooler air scoops. Refer to para-graph 4-152. b. Open aft gearbox cowl doors. Refer to paragraph 4-152. c. Remove oil cooler fairing from around aft side of oil coolers. Refer to paragraph 4-152.


4-120 Change 4

Lubricating Oil 1 d. Drain oil coolers, using drain valves (7 and 10, figure 4-47) in service deck under gearbox. e. Working under oil cooler air duct, disconnect tubes (5 and 15) and hoses (12 and 16) from bottom ports of oil coolers. Cap hoses and tubes and ports of oil coolers to prevent contamination. f. Remove four bolts and washers securing both oil coolers (3 and 18) to structure. Remove both oil coolers as a unit. g. Remove three bolts, nuts and washers securing oil coolers together. h. If an oil cooler is to be replaced, note position of connectors, and remove connectors and fittings along with attaching nuts and washers, for use on replacement oil cooler. 4-168. CLEANING EXTERIOR OF OIL COOLERS. a. Machine spray cleaner, type MA-1, or other suitable spray type cleaners, including portable or barrel pump type, may be used for cleaning exterior of oil coolers. Use of a nonmetallic brush to scrub extremely soiled areas may be necessary.

Cleaning Compound 11

Drycleaning Solvent 7 b. Alkaline cleaning compound, MIL-PRF-87937, is used for aerospace cleaning. Mix one

part cleaning compound with 10 to 15 parts water for moderate to lightly soiled areas. Stubborn or exceptionally oily areas may be cleaned with drycleaning solvent, MIL-PRF-680, Type II, in small quantities before application of cleaning compound solution, MIL-PRF-87937. c. Cleaning procedures: 1. Cleaning shall be accomplished in an approved area where drain-off and/or solvent will not enter a public sewer or otherwise be allowed to contaminate streams or lakes. 2. Apply cleaning compound solution, MIL-PRF-87937, by spraying into rear of cooler, then front of cooler. Adjust washer to provide sufficient pressure to force mixture through cooler fins. Agitate the compound as required by scrubbing with a nonmetallic brush. Allow mixture to soak approximately 5 to 10 minutes before rinsing. 3. Thoroughly rinse exterior of oil coolers using large amounts of water. 4. Inspect for cleanliness; some particles may require removal by hand or by use of drycleaning solvent, MIL-PRF-680, Type II. 4-169. INSTALLATION - ENGINE OIL COOLERS. a. Position left and right engine oil coolers together and align mating lugs. Install three bolts, washers and nuts. (Use a washer under bolthead and under nut.) b. If an oil cooler is being replaced, install connectors on cooler parts. Use new gaskets, and align connector to same position as it was installed on removed oil cooler. c. Install assembled coolers (3 and 18, figure 4-47) to structure, using four bolts and washers. Torque 50 to 70 inch-pounds. (QA) d. Torque lines (5 and 15) 200 to 350 inch-pounds; torque lines (12 and 16) 300 to 480 inch-pounds. (QA) e. Close drain valves (7 and 10). f. Perform operational check. Inspect oil coolers and connections for leaks.


Change 4 4-121

g. Install fairing around oil cooler using screws and washers. Refer to paragraph 4-152. 4-170. REMOVAL – REDUCTION GEARBOX OIL COOLER.

NOTE

The gearbox oil cooler is a two section cooler built as a single unit. One section is the cooler for gearbox oil, and the other section is for transmission oil.

a. Remove oil cooler fairing from around oil coolers. Refer to paragraph 4-152.

Lubricating Oil 1 b. Drain oil coolers, using drain valves (7 and 10, figure 4-47) in service deck under gearbox. c. Remove four bolts and washers securing oil cooler (1) to structure. d. Pull cooler away from structure and disconnect hoses (13, 14 and 19). Remove cooler. e. If cooler is to be replaced, note position of connectors and remove connectors and fittings, along with attaching nuts and washers for use on replacement oil cooler. 4-171. INSTALLATION – REDUCTION GEARBOX OIL COOLER. a. If oil cooler is being replaced, install connectors on oil cooler ports. Use new gaskets, and align connector to same position as it was installed on removed oil cooler. b. Position cooler (1, figure 4-47) and connect hoses (13, 14 and 19). Torque (13 and 14) 500 to 850 inch-pounds and (19) 300 to 480 inch-pounds. (QA)

CAUTION

Assure that inlet hoses are connected to inlet ports of cooler, as determined by directional arrows, or by color coding.

c. Secure cooler (1) to structure with four bolts and washers. Torque 50 to 70 inch-pounds. (QA) d. Clean drain valves (7 and 10). e. Perform operational check. Inspect oil coolers and connectors for leaks. f. Install fairing around oil coolers, using screws and washers. Refer to paragraph 4-152. 4-172. OIL COOLER BLOWERS. Two shaft driven blowers are mounted on upper aft pads of the reduction gearbox. The blowers provide air, through connecting ducts, to assure an adequate air flow through the oil coolers. 4-173. REMOVAL.

NOTE

Either of the blowers may be replaced individuality.

a. Open engine top and upper side cowl. Refer to paragraph 4-152. b. Open oil cooler air scoop. Refer to paragraph 4-152. c. Remove gearbox top cowl. Refer to paragraph 4-152. d. Remove ejector. Refer to paragraph 4-158. e. Loosen clamps securing boot (2, figure 4-48) to blower (1). f. Remove nuts (4) and washers (5) and remove blower. Remove and discard gasket (7) and packing (6). Remove boot from blower. g. Cover gearbox mounting pad if replace-ment is not to be accomplished immediately.


4-122

Figure 4-47. Oil Coolers and Lines (Sheet 1 of 2)


4-123

Figure 4-47. Oil Coolers and Lines (Sheet 2)


4-124 Change 4

Figure 4-48. Oil Cooler – Blowers


Change 5 4-125

4-174. INSPECTION. a. Inspect oil cooler blower for damage and wear limits per figure 4-49. b. Use aluminum oxide abrasive cloth, ANSI-B74.18, to smooth all minor nicks, scoring and scratches on non-critical surfaces. c. Replace damaged oil cooler blower. 4-175. INSTALLATION. a. Position boot (2, figure 4-48) on blower (1) with large diameter clamp aft. b. Install packing (6) on shaft of blower. Install new gasket (7) on blower. Position blower (1) to gearbox mounting pad, and secure blower with washers (5) and nut (4). Torque 160 to 190 inch-pounds. (QA) c. Slide boot (2) aft, and secure clamps on oil cooler duct (3) and blower (1). d. Install ejector. Refer to paragraph 4-159. e. Install gearbox top cowl. Refer to para-graph 4-152. f. Close oil cooler air scoop. Refer to para-graph 4-152. g. Close engine top and upper side cowl. Refer to paragraph 4-152. 4-176. ENGINE MOUNTS. 4-177. MAINTENANCE. Mounts are structural members; inspection and repair shall be in accordance with figure 4-50 and NAVAIR 01-110HCE-3. Replacement of unserviceable components can be accomplished while engine is removed. Replacement of engine tripod and bipod mount assembly rod end bearings, clevis fittings, and associated bolts and Hi-lok fasteners (3 and 4, figure 4-51) is authorized for Depot Level repair only, and is cause for replacement of entire assembly if wear or damage limits are exceeded. Fittings (1 and 2) are installed on the engine in build-up of the power package quick-change assembly. Deck

fittings (5 and 9) are shimmed for proper align-ment and will normally be left in place. 4-178. REMOVAL. a. With engine supported on lifting sling, remove bolts with nuts and washers to detach forward mount vertical tubes (6, figure 4-51) from fittings (7), and aft bearings (2) from bipod (3) and tripod (4). b. After lifting engine, remove forward mount tubes from fittings (1) on accessory gearboxes. Detach bipod and tripod from deck fittings (5) by removing nuts, washers and bolts. 4-179. INSTALLATION.

CAUTION

If removal of any deck fitting becomes necessary, keep shims in original locations and maintain identical thickness. If shims are lost or altered, alignment procedure will be required in accordance with NAVAIR 01-110HCE-3.

a. Position bipod (3, figure 4-51) and tripod (4) in deck fittings (5). Install bolts from outboard and higher sides of fittings, and secure with washers and nuts. Torque nuts 120 to 150 inch-pounds. (QA)

CAUTION

If pivot fitting is to be assembled with the tube assembly, ensure bushing is installed in pivot fitting. Failure to do so could cause excessive play and stress on attaching bolt.

b. Assemble tube (10) and two fittings (7) attached together by bolts with thin washers next to heads and nuts. Torque nuts 30 to 40 inch-pounds and secure with cotter pins. (QA) c. Position forward mount tubes assembly in deck fitting (9). Align each bellcrank fitting pivot with mounting holes and install bolt with thin washers next to head and nut. Torque nut 30 to 40 inch-pounds and secure with cotter pin. (QA)


4-126

Figure 4-49. Blower – Wear Limits


Change 4 4-127

d. If fittings (1, figure 4-51) and bearings (2) were removed from engine, install as follows: 1. Position each forward fitting on mounting pad at underside of accessory gearbox and secure with three bolts and washer. Torque bolts 275 to 300 inch-pounds and Iockwire boltheads together. (QA)

NOTE

Right and left front mount fittings for the accessory gearbox are different. Assure that the correct fitting is used in the proper position.

2. Position each aft bearing assembly on mounting pad at underside of reduction gearbox. Install two outboard bolts and washers on starboard side and two inboard bolts and washers on port side. Position jackshaft mount on outboard flanges of port bearing and inboard flanges of starboard bearing. Install bolts and washers. Torque bolts 275 to 300 inch-pounds and Iockwire boltheads in pairs. (QA) e. Before installing engine, attach forward tubes (6) in fittings (1) with bolts installed using thin washers under boltheads and nuts. Torque nuts 30 to 40 inch-pounds and secure with cotter pins. (QA) f. While lowering engine, align aft bearings (2) in forks of bipod and tripod. Install bolts (longest bolt through tripod) and secure with washers and nuts, torque 450 to 550 inch-pounds. Align forward tubes (6) in fittings (7) and install bolts from forward side, with thin washers under boltheads and nuts. Torque nuts 30 to 40 inch-pounds and secure with cotter pins. (QA) 4-180. ENGINE COMPARTMENT FIRE EXTIN-GUISHER INSTALLATION. 4-181. MAINTENANCE. a. Containers will be replaced when depleted, as shown by pressure gage indication

not within limits for ambient temperature. Removed containers shall be recharged and serviced by qualified personnel in accordance with applicable directives. b. Fire detectors and electrical components shall be maintained according to instructions in NAVAIR 01-110HCE-2-11.

NOTE

Recharge kits and cartridges (squibs) supplied by two manufacturers, Walter Kidde (CAGE 33525) and HTL Advanced Technology Industries (CAGE 33252), are not interchangeable.

c. To prevent gage corrosion, seal gage glass as follows:

Drycleaning Solvent 7 1. Lightly wipe and clean gage where gage body is crimped around sight glass. Use a soft cloth slightly wet with drycleaning solvent, MIL-PRF-680, Type II. Allow 15 minutes for drycleaning solvent to completely evaporate from gage surface.

Silicone Rubber Adhesive 10 2. Apply a thin bead of adhesive, MIL-A-46106, around entire circumference of gage where glass cover and metal case join. Allow 72 hours for adhesive-sealant to cure.


4-128 Change 2

Figure 4-50. Engine Mounts – Wear Limits (Sheet 1 of 2)


4-129

Figure 4-50. Engine Mounts – Wear Limits (Sheet 2)


4-130 Change 4

Figure 4-51. Engine Mounts


Change 6 4-131

4-182. INSPECTION AND REPAIR. (Figure 4-52.)

WARNING

No personnel are permitted in the fire extinguisher discharge area during main-tenance on fire extinguisher system, including replacement of squibs/ cartridges. All personnel replacing squibs/ cartridges shall wear safety glasses.

If lines are removed from fire extinguisher container, the personnel performing any work on the squib/cartridge shall not be in line with container discharge port.

a. Visually check both extinguisher containers for indication on gages (10) of pressure within limits for temperature range, and for presence of red indicator disc (9). Replace container if depleted. Replace indictor if disc is missing. Proceed as follows: 1. Open cowling. Disconnect tubes from outlet fittings and hose from thermal relief fitting. Disconnect electrical wiring from cartridge terminals. Remove bolts at container mounting lugs. Remove container assembly. (a) Inspect fire extinguisher container for nicks, cracks, corrosion, crossed threads, chafing, scoring and other defects. Dents deeper than 1/16 inch per inch of average dent diameter, or scratches deeper than 0.004 inch will be cause for rejection. 2. If disc is missing, disconnect hose from indicator. Remove six screws around flange and remove indicator. Transfer nipple to replacement indicator. 3. Insert indicator in mounting hole. Connect hose to nipple. Install six mounting screws with nuts and washers.

WARNING

Assure electrical wiring connection is correct. Refer to NAVAIR 01-110HCE-2-11 for information and to NAVAIR 01-110HCE-2-13 for wiring diagram. Incorrect wiring can cause wrong fire extinguisher to be discharged.

4. Position replacement container (6) on supports (5 and 7). Install bolts, washers and nuts. Connect hose from indicator to fill and thermal relief fitting on container. Connect tubes to discharge outlet fittings. Connect electrical wiring to cartridge ground and actuator terminals.

b. Visually inspect all tubes for cracks, dents, corrosion and security of installation. Inspect discharge holes in manifolds (2) and forward tubes (1) for obstructions or restrictions. Replace unserviceable parts. 1. Weighing engine fire extinguisher containers (6).

NOTE

Use a weighing scale with a maximum range of 0 – 50 pounds, with 0.01 pound increments and an accuracy of plus/minus 0.1 percent. The fire extinguisher configuration for all weighings shall not include the cartridges (3).

(a) Place fire extinguisher on scale and read weight. If weight does not match the weight etched on the data plate (within plus or minus 1.0 percent or 0.25 pounds, whichever is less), the fire extinguisher must be replaced. c. Replacement of Squibs/Cartridges. 1. Replace squibs/cartridges in container, (HTL Industries) as follows: (a) Turn off electrical power and dis-connect battery. (b) Disconnect electrical leads from container squibs/cartridges (two terminals). (c) Connect the two terminals on each squib/cartridge with a (shunt) electrical connec-tion. The shunt shall remain connected at all times when the squib/cartridge is disconnected from the aircraft wiring.

WARNING

To prevent accidental discharge of con-tainer during squib/cartridge replacement, hold the large (1-1/4 inch) hex housing assembly to prevent turning.

(d) Remove squib/cartridge from housing.

Grease 6 (e) Apply grease, SAE AMS-G-4343, to threads of replacement squib/cartridge assembly.


4-132

Figure 4-52. Fire Extinguisher Installation


Change 6 4-133

WARNING

To prevent accidental discharge of con-tainer during squib/cartridge installation, hold the 1-1/4 inch hex housing assembly to prevent turning.

CAUTION

Install squib/cartridge having 8-32 actuate terminals.

(f) Place packing on squib/cartridge assembly and install in housing. Torque squib/ cartridge assembly 70 to 80 inch-pounds while holding 1-1/4 hex housing to prevent housing from turning in container and lockwire. (QA)

WARNING

Assure electrical wiring connection is correct. Refer to NAVAIR 01-110HCE-2-11 for information and to NAVAIR 01-110HCE-2-13 for wiring diagram. Incorrect wiring can cause wrong fire extinguisher to be discharged.

(g) Remove shield or shorting device (shunt) from cartridge and connect aircraft wiring. 2. Replace squib/cartridges in container, (Walter Kidde Co.,) as follows: (a) Turn off electrical power and dis-connect battery. (b) Disconnect electrical leads from container squib/cartridges (two terminals). (c) Connect the two terminals on each squib/cartridge with an electrical connection (shunt). The shunt shall remain connected at all times when squib/cartridge is disconnected from the aircraft wiring.

NOTE

Observe location of ground washer terminal in order to permit installation in same position.

(d) Loosen squib/cartridge while holding valve to keep from turning.

(e) Hold ground washer and remove squib/cartridge.

Grease 6 (f) Apply grease, SAE AMS-G-4343, to threads of the replacement squib/cartridge.

CAUTION

Insert squib/cartridge having 10-32 actuate terminals.

(g) Insert cartridge through ground washer and screw into valve. Direct ground washer to same position as when removed. Torque cartridge 150 to 200 inch-pounds and lockwire. (QA)

WARNING

Assure electrical wiring connection is correct. Refer to NAVAIR 01-110HCE-2-11 for information and to NAVAIR 01-110HCE-2-13 for wiring diagram. Incorrect wiring can cause wrong fire extinguisher to be discharge.

(h) Remove shield or shorting device (shunt) from cartridge and connect aircraft wiring. 4-183. STARTER-GENERATOR. 4-184. DESCRIPTION. Two starter-generators are mounted on upper front of each power section accessory gearbox, extending above the cabin roof under the engine air inlet fairings. 4-185. MAINTENANCE. Replace either starter-generator according to instructions below if malfunction occurs. Refer to NAVAIR 01-110HCE-2-11, Electrical Systems, and to NAVAIR 01-10HCE-2-13, Wiring Diagrams, for further information. 4-186. REMOVAL. a. Open transmission forward fairing. Refer to paragraph 4-152.


4-134 Change 6

b. Remove engine air inlet fairing for access to starter-generator. Refer to paragraph 4-152. c. Disconnect starter-generator cable at con-nector on cabin roof. Disconnect two electrical wires from terminals at each end of terminal block on starter-generator. d. Disconnect air duct and clamp from forward end of generator. e. Support starter-generator while removing clamp which secures unit to accessory gearbox. Remove starter-generator. 4-187. BUILDUP. a. Install air duct cap with openings at 12 o'clock position. Torque clamp nut 20 to 25 inch-pounds and Iockwire. (QA) b. Install electrical cables on terminals B, C and E as per NAVAIR 01-110HCE-2-13 wiring schematic. Torque nuts 160 to 190 inch-pounds. (QA) 4-188. INSTALLATION.

Grease 6 a. Coat male and female splines with Plasti-lube No. 3 (CAGE 02307) or equivalent. b. Insert shaft of starter-generator into accessory gearbox drive pad, assuring proper spline engagement. c. Position starter-generator with terminal block at 12 o'clock, and install clamp to secure starter-generator to base adapter. Torque clamp 50 to 70 inch-pounds and Iockwire. (QA) d. Connect air duct to forward end of unit with clamp.

e. Connect starter-generator cable to connector on cabin root. Connect two small electrical wires to end terminals A and D on block. Torque 20 to 25 inch-pounds. (QA)

CAUTION

Assure the angle of the No. 1 generator exhaust housing does not cause binding or interfere with the Ng power lever controls by rotating the No. 1 throttle to the full open position.

f. Install engine air inlet fairing and close forward fairing. Refer to paragraph 4-152. 4-189. POWER PLANT CHANGE PROCEDURES.

NOTE

Prior to a complete power plant package change, ascertain that the trim bias value on records is the same as that on the respective power section data plate.

4-190. The following paragraphs outline pro-cedures for replacement of a complete power plant package. a. The power plant shall not be preserved or depreserved until it is installed in the helicopter or installed in a test stand. b. For proper sling use during power plant handling see figure 4-53 for correct cables, lifting points and balancing position of lifting eye to prevent damage. c. For further details of removal and installation of accessories and components, refer to applicable preceding instructions in this section for those systems. Where bolt or nut torques are not specified, use standard torque values. (Refer to NAVAIR 01-110HCE-2-1.)


Change 4 4-135

Figure 4-53. Use of Lifting Sling and Stand (Sheet 1 of 2)


4-136 Change 2

Figure 4-53. Use of Lifting Sling and Stand (Sheet 2)


Change 7 4-137

4-191. The following engine accessories, installation hardware, and system components shall be inspected after power plant package removal or prior to power plant package installation. a. Remove oil cooler blower. (Refer to paragraph 4-172.) Inspect blower for damage, drains and drain lines for obstructions and drain line assembly for damage. b. Remove exhaust ducts (paragraph 4-158.) and thoroughly inspect for damage. c. Remove main driveshaft engine adapter (NAVAIR 01-110HCE-2-4) and send to intermediate maintenance facility for inspection.

Fluorescent Penetrant 12 d. Inspect engine mount fittings for obvious damage. Apply fluorescent penetrant, ASTM E1417, to detect any cracks per NAVAIR 01-1A-16. e. Inspect engine mount fitting bearings for excessive play. Maximum allowed is 0.015 inch axial and 0.005 inch radial. f. Inspect attaching bolts, nuts, studs and washers for damage, condition of plating and condition of threads. g. Inspect clamps and chafing strips for damage and security of attachment. h. Inspect hose assemblies for damage, cover deterioration, proper routing, broken braid wires (no more than two adjacent broken wires or six per linear foot), and proper identification and color coding bands. i. Inspect metal tubing and end fittings for damage and proper identification and color coding bands. j. Inspect fireshield for damage, fastener problems and deteriorated fire seal chafing strips.

k. Inspect pressure transmitter and brackets for damage and security for attachment. I. Inspect the gas producer tachometer-generator and power turbine tachometer-generator for damage and security of attachment. m. Inspect complete firewall installation for damage and fasteners for security and wear. n. Inspect electrical system wiring and wiring components for damage, continuity, proper routing, security of attachment, sealant, proper Iockwiring and legibility of control and maintenance markings. o. Inspect pressure switches for damage and security of attachment. 4-192. POWER PLANT PACKAGE. The power plant package consists of two power sections and a reduction gearbox built up as a quick-change assembly. 4-193. REMOVAL.

CAUTION

Care must be exercised to prevent entrance of dirt and foreign materials into the engine during power section removal and installation. Whenever practicable, temporary covers should be used to seal all the openings of a dismantled engine. To protect the exhaust case outlet from foreign objects, an exhaust flange cover shall be used. Cover is to be replaced as soon as possible if removed. If the reduction gearbox is not adequately protected from contamination in the input shaft area, premature bearing failure may occur. To protect the reduction gearbox from contamination, ensure the reduction gearbox mating flanges are covered following removal of power sections. If cover is removed, replace it as soon as possible. During power section removal, examine exposed engine parts for scoring, burning or any other visible signs of damage. If internal damage to the reduction gearbox is discovered, the


4-138 Change 7

entire twin-pac may need to be replaced. Take note of the physical condition and location of signs of damage on the power section which would not be evident after cleaning. Remove and discard all preformed packings exposed by removal of the power section. Ensure new preformed packings are installed prior to new power section installation.

NOTE

On-wing single power section changes are authorized with intermediate level assistance. Utilize instructions in this manual and the intermediate maintenance manual NA 02B-20AA-6-1, as applicable, to accomplish single power section changes.

a. Turn off all electrical switches and disconnect any electrical power source. Disconnect battery. b. Open and remove cowling: 1. Open transmission fairing (1, figure 4-54). 2. Open both engine side cowlings. Remove lower cowl doors (12). 3. Remove left and right air inlet fairings (2 and 3).

NOTE



4-139

4. Disconnect starter-generator cooling ducts at starters. Remove right and left engine top cowls with attached side cowls (4 and 5, figure 4-54). 5. Remove twin gearbox side cowling (11) at each side. 6. Open oil cooler air scoops (9). Remove left twin gearbox top cowl (8) with attached air scoop. 7. Disconnect anticollision light electrical connector. Disconnect each reduction gearbox oil filler adapter from top panel (7) by removing screws. 8. Disconnect gearbox vent hose (2, figure 4-55) from fitting (1) on left exhaust ejector detach hose support clamp and spacer from cowling by removing screw (3). 9. Remove top panel and right twin gearbox top cowl (6, figure 4-54) with attached air scoop as an assembly. 10. Remove top frame (14) of oil cooler support (10) above horizontal centerline of exhaust ejectors. c. Remove exhaust ejector, with upper aft firewall section as an assembly, from left and right sides. 1. Disconnect drain tube (5, figure 4-56) from fitting (1). Detach oil filler hose, clamp and vent hose bracket (7, figure 4-55) from bracket (6) on inboard side of left ejector. 2. Remove bolts, to detach outer ends of two ejector links (2, figure 4-56) from brackets on oil cooler support, at lower and outboard sides of ejector. 3. Remove screws and stiffeners (7) which secure engine fireshield to front of aft firewall, screws which secure upper section (3) to lower section (4) of firewall, and screws which secure upper section to centerline firewall (8) and center section of aft firewall (6).

4. Remove ejector with attached firewall section. d. Remove screws to detach center section (6) of aft firewall from lower section, above tail rotor drive shaft tunnel, and from flange of centerline firewall. This center section of aft firewall will be removed with engine assembly. e. Remove main driveshaft. Remove drive-shaft adapter, using T101588 wrench. f. Remove remaining screws to detach centerline firewall upper web (trough) from lower section and from mid-firewall and induction baffle. (See figure 4-57.) Lift out centerline firewall trough. g. Remove side panels (7, figure 4-58) with attaching screws, from left and right sides of induction baffle, below air ducts. Disconnect compressor wash hose (13) at wash ring. h. Remove screws inside engine inlet baffles. i. Remove upper sections of induction baffle (1) and middle firewall (2) with attached inlet duct (3), air valve (4), and transmit duct (6), as an assembly from each aide. 1. Disconnect air management valve electrical connector (5) on front of middle firewall above inlet duct. 2. Remove screws to detach upper sections of induction baffle (1) and middle firewall (2) from lower sections along break lines illustrated. 3. Detach cowl hold-open strut (8) from stowage bracket on lower section of firewall. 4. Lift off firewall-baffle-duct assembly. 5. Remove screws from induction baffle (11) panels in lower section of middle firewall (10) to allow better access to bolts at lower ends of forward mount vertical tubes.


4-140

Figure 4-54. Cowl Installation


Change 4 4-141

6. Remove screws to detach left and right inboard ears of lower sections of induction baffle (9, figure 4-58) from lower centerline firewall. 7. Flex left and right inboard ears of lower middle firewall (10) and induction baffle section (9) forward to allow engine removal clearance, and secure with lockwire. j. Remove access doors from bulged areas on cabin aft bulkhead, at each side of pylon support.

Lubricating Oil 1 k. Open oil drain valves on front of each accessory gearbox and on deck aft of reduction gearbox. Drain oil into suitable container. I. Disconnect power lever controls links (1, figure 4-59) from lever on manual fuel control.

Aviation Turbine Fuel 2 m. Disconnect fuel lines from each power section as follows: 1. Fuel inlet hose at top of tube (3) at level of cabin roof. 2. Combustion chamber drain hose (14) and fuel manifold drain hose (15) at tee fitting on engine deck. 3. Governor bleed line hose (7) at lower end. n. Disconnect flexible boots from oil cooler blowers (1 and 12, figure 4-60).

NOTE

If engine is to be reinstalled, disconnect forward boot clamp and remove blower from pad. Slide blower back into oil cooler housing and leave on airframe.

o. Disconnect oil lines as follows: 1. Accessory gearbox drain hoses (8, figure 4-59). 2. Oil filler flexible tubes (5) from airframe filler receptacle. 3. Engine and gearbox cooler line hoses (2, 7 and 11, figure 4-60) at rear side of reduction gearbox. 4. Blower seal drain hoses (3 and 10) at deck aft of reduction gearbox. 5. Output shaft seal drain hose (14) from union on drain tube (3) at left side. p. Disconnect and tag electrical connectors as follows: 1. Starter-generator cables (2, figure 4-59). 2. Accessory gearbox harness at firewall receptacles (4). 3. Fuel filters (6). 4. Idle stop solenoids (9). 5. Engine harness and ignition leads from three places on ignition exciter (11). 6. Governor RPM actuator (13). 7. Bleed air valves (16). 8. Electrical harnesses (4 and 9, figure 4-60) at receptacles on deck aft of reduction gearbox. 9. Fire detector connectors (6 and 8) at aft firewall.


4-142

Figure 4-55. Reduction Gearbox Vent Hose and Oil Filter

q. Disconnect bleed air tubes at valves (16, figure 4-59). r. Disconnect governor RPM actuator (13) from jackshaft (18). s. Install engine sling, attached to a hoist.

WARNING

Lifting or hoisting shall be done by designated personnel. The load capacity rating shall be clearly marked on hoist. Do not exceed load rating. Inspection and testing for cracks or defects in hoist system shall be performed on a regular basis. Use only pins, links, and hooks

recommended for lifting specific engine. Before lifting, alert personnel in immediate areas. Before lifting, balance the load. Do not stand under load while it is being moved from one area to another on a hoist. Do not stand under load to do maintenance work.

NOTE

Use suitable maintenance hoist of (905 lb. minimum capacity) with minimum lift clearance of 8 feet.

t. Disconnect forward engine mount tubes (10, figure 4-59) removing bolts at either end as accessible.


4-143

Figure 4-56. Removal of Exhaust Ejectors and Upper Aft Firewall


4-144

Figure 4-57. Removal of Upper Centerline Firewall

u. Disconnect (aft) engine mounts by removing two bolts (19, figure 4-59) at top of tripod and bipod. v. Lift engine assembly from airframe. Assure tubes and cables are free as engine is lifted. w. Remove forward mount tubes from fittings on accessory gearboxes. Install engine assembly in handling stand. x. Remove necessary items from removed engine assembly and install on new QEC.

4-194. INSPECTION. a. Inspect power plant package or power section for visible signs of damage. b. Refer to NAVAIR 01-110HCE-2-1 for conditional inspections applicable to power plant package or power section. However, do not perform post-installation inspection procedures. c. If any irregularities are found, tag power plant or power section and return to IMA for complete inspection.


4-145

Figure 4-58. Removal of Upper Induction Baffle and Middle Firewall with Attached Ducts


4-146

Figure 4-59. Engine Connections (LH Side Shown)


4-147

Figure 4-60. Engine Connections (Aft Side Shown)


4-148 Change 7

4-195. INSTALLATION.

CAUTION Care must be exercised to prevent entrance of dirt and foreign materials into the engine during power section removal and installation. Whenever practicable, temporary covers should be used to seal all the openings of a dismantled engine. To protect the exhaust case outlet from foreign objects, an exhaust flange cover shall be used. Cover is to be replaced as soon as possible if removed. If the reduction gearbox is not adequately protected from contamination in the input shaft area, premature bearing failure may occur. To protect the reduction gearbox from contamination, ensure the reduction gearbox mating flanges are covered following removal of power sections. If cover is removed, replace it as soon as possible. During power section removal, examine exposed engine parts for scoring, burning or any other visible signs of damage. If internal damage to the reduction gearbox is discovered, the entire twin-pac may need to be replaced. Take note of the physical condition and location of signs of damage on the power section which would not be evident after cleaning. Remove and discard all preformed packings exposed by removal of the power section. Ensure new preformed packings are installed prior to new power section installation. Assure helicopter wiring harness terminals do not contact any portion of power section ITT lug shield or gas generator case after retaining nuts are torqued.

NOTE

On-wing single power section changes are authorized with intermediate level assistance. Utilize instructions in this manual and the intermediate maintenance manual NA 02B-20AA-6-1, as applicable, to accomplish single power section changes.

Perform ITT loop resistance check before installing power section(s).

Engine realignment may be required. Refer to NAVAlR 01-110HCE-2-4 Engine to Transmission Driveshaft Alignment for specific requirements.

a. Check that power package is prepared for installation. 1. Assembly shall be built-up in accordance with QEC instructions. 2. Other required parts will be transferred between removed assembly and replacement assembly. 3. Ignition exciters will be removed from shipping location on accessory gearboxes of replacement assembly, and either used to replace units mounted on middle firewall braces or installed on removed power package, according to local directives. 4. Position center section of aft firewall (6, figure 4-56) between power sections, behind aft fireshields.

WARNING

Lifting or hoisting shall be done by designated personnel. The load capacity rating shall be clearly marked on hoist. Do not exceed load rating. Inspection and testing for crack or defects in hoist system shall be performed on a regular basis. Use only pins, links, and hooks recommended for lifting specific engine. Before lifting, alert personnel in immediate areas. Before lifting, balance the load. Do not stand under load while it is being moved from one area to another on a hoist. Do not stand under load to do maintenance work.

b. Use engine sling and suitable maintenance hoist to lift power package from stand. (See figure 4-53.) c. Attach each forward mount vertical tube (6, figure 4-51) to fitting (1) on accessory gearbox. Install bolts, using thin washers under bolthead and nut. Torque nut 30 to 40 inch-pounds and secure with cotter pin. (QA)



d. Lower engine carefully into place, checking position as follows: 1. Forward and middle fireshields will be aft of lower induction baffle (9, figure 4-58) and lower middle firewall (10). 2. Aft fireshield will be on forward side of lower aft firewall (4, figure 4-56). Guide center section (6) of aft firewall to mating position.

WARNING

Use of hands vice mechanical fingers could result in personal injury due to the confined work space.

e. Align forward mount vertical tubes (6, figure 4-51) on fittings (7) using mechanical fingers. Install bolts, using thin washers under bolthead and nut. Torque nuts 30 to 40 inch-pounds and secure with cotter pin. (QA)

CAUTION

Assure long bolt is installed in tripod and short bolt in bipod.

f. Align aft mount bearing in forks of bipod and tripod. Install bolts (19, figure 4-59) from inboard, with thin washers under nuts. Torque 450 to 550 inch-pounds. (QA)


4-149

g. Connect power lever control links (1, figure 4-59) to lever on manual fuel controls. h. Connect electrical connectors. 1. Starter-generator cables (2) at receptacle on cabin roof. 2. Accessory gearbox harnesses at firewall receptacles (4). 3. Fuel filters (6). 4. Idle stop solenoids (9). 5. Ignition leads to two top connections on ignition exciter (11) and engine harness lead to lower connector. 6. Governor RPM actuator (13). 7. Bleed air valves (16). (Customer) 8. Electrical harnesses (4 and 9, figure 4-60) at receptacles on deck aft of combining gearbox. 9. Fire detector connectors (6 and 8) at aft firewall. i. Connect oil lines as follows: 1. Output shaft seal drain hose (14) to union on drain tube (3) at left side. 2. Blower seal drain hoses (3 and 10) at deck aft of reduction gearbox. 3. Engine and gearbox cooler line hoses (2, 7 and 11). 4. Oil filler flexible tubes (5, figure 4-59) to fittings on airframe filler receptacle. 5. Accessory gearbox drain hoses (8). j. Connect fuel lines from each power section as follows: 1. Inlet hose at top of tube (3) at lever of cabin roof.

2. Combustion chamber drain hose (14) and fuel manifold drain hose (15) at tee fitting on engine deck. 3. Governor bleed line hose (7) to tube below accessory gearbox. k. Connect governor RPM actuator (13) to jackshaft (18). I. Install boots on oil cooler blowers (1 and 12, figure 4-60). m. Install screws securing left and right inboard ears of induction baffle (9, figure 4-58) to lower centerline firewall. n. Install screws in induction baffle (11) panels in lower sections (10) of middle firewalls. o. Install upper centerline firewall. (See figure 4-57.) 1. Position upper web (trough) of centerline firewall. 2. Install screws attaching upper web to lower centerline firewall, forward firewall, induction baffle, middle firewall and lower and center portions of aft firewall. p. Install upper sections of induction baffle (1, figure 4-58) and middle firewall (2) with attached inlet duct (3), air valve (4), and transition duct (6) as an assembly on each side. 1. Position firewall-baffle-duct assembly. 2. Install screws to attach upper and lower sections of induction baffle and middle firewall. 3. Connect air management valve electrical connector (5) on front of firewall above inlet duct. 4. Connect hose to water wash ring and install side panel (7) of induction baffle.


4-150 Change 6

NOTE

If alignment is required, do not install driveshaft until alignment has been completed.

q. Install main driveshaft adapter. Install driveshaft. r. Install upper aft firewall and exhaust ejector assembly on each side. (See figure 4-56.) 1. Install screws attaching center section (6) of aft firewall to lower section (4). 2. Install inboard stiffener (7) over fire-shield and attach to front of aft firewall with screws. 3. Position upper firewall (3) and ejector (1) assembly. Install remaining stiffeners and screws. 4. Attach outer ends of two ejector links (2) to brackets on oil cooler support with bolts, using thin aluminum alloy washers under boltheads and nuts. 5. Connect drain tube (5) to fitting on outboard lower side of ejector. Connect gearbox vent hose (2, figure 4-55) to fitting (1) on left ejector. Attach vent hose clamp bracket (7) and clamp of oil filler hose (5) to bracket (6) on inboard side of ejector with screw, washer and nut.

s. Perform complete engine rigging and operational checks. t. Install cowling. 4-196. POST INSTALLATION INSPECTION PROCEDURES. After installation, check fuel and engine oil servicing. Prepare for ground run:

NOTE

Torque transmitters must be adjusted to the installed reduction gearbox using the torquemeter correction factors provided in the reduction gearbox section of the logbook. Therefore adjustment of the torque transmitters is required each time a replacement reduction gearbox is installed on the aircraft.

a. Perform torque transmitter operational check per NAVAIR 01-110HCE-2-10. b. Perform adjustment of the torque transmitters per NAVAIR 01-110HCE-2-10. c. Perform engine inlet temperature indicating system operational check per NAVAIR 01-110HCE-2-10. d. Perform power turbine tachometer indicator system operational check per NAVAIR 01-110HCE-2-10. e. Perform gas producer tachometer indicator system operational check per NAVAIR 01-110HCE-2-10.

All information on pages 4-151 through 4-154, including figure 4-61 and table 4-3, has been deleted.


Change 6 4-155

4-197. ENGINE WATER WASH PROVISIONS. (See figure 4-45.) An engine water wash system provides a means of cleaning the engine internally for anticorrosion purposes or to improve performance when performance has deteriorated due to accumulation of foreign material deposits. 4-198. DESCRIPTION. The engine water wash provisions consists of hoses (1, figure 4-45), cap assemblies (2), spray ring (4) and hardware necessary to mount fittings on baffles (3) and provide for connection between the external corrosion control spraying unit and the water wash ring on the engine. 4-199. REMOVAL. Disconnect hose (1, figure 4-45) at water spray ring (4) and at plug (2) on baffle and remove hose. Repeat on opposite side. Close immediately with closure cap to prevent entry of foreign matter.

4-200. INSPECTION. a. Inspect hoses and tubes for leaks, cracks, damage and serviceability. b. Inspect tees, reducers and bulkhead fittings for damaged threads, cracks, leaks or damage. c. Inspect plugs and caps for damage and security of attachment. 4-201. REPAIR OR REPLACEMENT. Replace hoses, tees or reducers, bulkhead fittings or caps that fail to meet inspection requirements. 4-202. INSTALLATION. Remove closure cap from spray ring (4) and attach hose (1) to tee.

All information on pages 4-156 through 4-161, including figures 4-62 through 4-66, has been deleted.


4-162

Figure 4-67. Accessory Locations (Sheet 1 of 4)


4-163

Figure 4-67. Accessory Locations (Sheet 2)


4-164 Change 5



4-165



4-166

4-203. FUEL SUPPLY SYSTEM. 4-204. OPERATION. (See figure 4-63.) Fuel supply system controls, valves, pumps and caution panel circuits are powered from the 28 VDC essential bus. When FUEL CONT ENG 1 and ENG 2 switches are ON, both boost will operate and both shutoff valves will open and deliver fuel through the filters to both engine power sections. If one switch is placed OFF, the corresponding shutoff valve will close but both boost pumps will continue to run. Circuits to shutoff valves are connected through the emergency switches so that if a FIRE PULL handle is used, the corresponding engine fuel shutoff valve will close. The interconnect valve between fuel pressure lines is opened or closed by the FUEL CONT CROSSFEED switch; when valve is open either pump can serve both power sections. Regardless of shutoff valves, when a boost pump is operating there is output through a flow-actuated switch to prevent a false caution panel indication of boost pump failure. 4-205. When there is fuel in aft cells, the underfloor cells will remain full by gravity feed and crossfeed. Fuel quantity gage indication, powered from the 115 VAC bus, will then be governed by the tank unit in the center aft cell. When the aft cells are empty, tank units in the right underfloor cell will control quantity gage readings. When fuel level drops below the float switch in the left underfloor cell, the FUEL LOW caution panel will illuminate. 4-206. Pressure fueling provisions include tandem sets of pilot and shutoff valves to protect against overfilling tank cells. When the float of either pilot valve element is raised to full-level position, the connected element of the dual shutoff valve is caused to close. 4-207. OPERATIONAL CHECKOUT. (See figure 4-68.) a. Pull out all circuit breakers. Place all switches to OFF or normal position. b. Place BATTERY switch ON. Close CAUTION LIGHTS circuit breaker. c. Place NON ESS BUS switch to MANUAL, and INVERTER switch to MAIN.

d. Close FUEL QTY circuit breaker. Observe reading on quantity indicator. Press FUEL QTY TEST switch and check that indicator pointer reads zero. Release test switch and check that indicator pointer returns to reading of fuel in tank.

NOTE

If amount of fuel is less than approxi-mately 10 percent of tank capacity, FUEL LOW caution panel segment should be illuminated.

e. Open FUEL QTY circuit breaker. Place INVERTER switch to OFF, and NON ESS BUS switch to NORMAL. f. Station an observer to watch two fuel shutoff valves and system interconnect valve, located inside cowling just ahead of engine compartment. Check operation of valves. 1. Close NO. 1 FUEL VALVE circuit breaker. Place ENG 1 FUEL CONT switch to ON. Check that left-hand fuel shutoff valve opens, as shown by position indicator (manual override handle).

CAUTION

Before next step, assure that MAIN and RESERVE FIRE EXT circuit breakers are open to avoid inadvertent discharge of fire extinguisher.

2. Pull FIRE 1 PULL handle to actuate emergency switch. Check that left-hand fuel shutoff valve closes. 3. Return FIRE 1 PULL handle to original position. Check that left-hand fuel shutoff valve opens. 4. Place ENG 1 FUEL CONT switch to OFF. Check that left-hand shutoff valve closes. Pull out NO. 1 FUEL VALVE circuit breaker. 5. Close NO. 2 FUEL VALVE circuit breaker. Place ENG 2 FUEL CONT switch to ON. Check that right-hand fuel shutoff valve opens.


4-167

CAUTION

Before next step, check that MAIN and RESERVE FIRE EXT circuit breakers are open.

6. Pull FIRE 2 PULL handle to actuate emergency switch. Check that right-hand fuel shutoff valve closes. Return handle to original position, and check that valve opens. 7. Place ENG 2 FUEL CONT switch to OFF. Check that right-hand fuel shutoff valve closes. Pull out NO. 2 FUEL VALVE circuit breaker. 8. Close FUEL CROSSFEED circuit breaker. Place FUEL CONT CROSSFEED switch to ON. Check that system interconnect valve opens. 9. Return FUEL CONT CROSSFEED switch to OFF. Check that interconnect valve closes. g. Close ENG 1 FUEL BOOST circuit breaker. Place ENG 1 FUEL CONT switch to ON. Check that left-hand fuel boost pump is operating and that LEFT FUEL BOOST caution panel segment is not illuminated. h. Return ENG 1 FUEL CONT switch to OFF. Check that left-hand boost pump is not operating. i. Place ENG 2 FUEL CONT switch to ON. Check that left-hand boost pump is operating. Return switch to OFF and check that pump stops running. Pull out ENG 1 FUEL BOOST circuit breaker. j. Close ENG 2 FUEL BOOST circuit breaker. Place ENG 2 FUEL CONT switch to ON. Check that right-hand fuel pump is running, and that RIGHT FUEL BOOST caution panel is not illuminated. Return switch to OFF and check that pump stops running. k. Place ENG 1 FUEL CONT switch to ON. Check that right-hand pump is running. Return switch to OFF and check that pump stops running. Open ENG 2 FUEL BOOST circuit breaker.

I. Check operation of auxiliary fuel system, if tanks are installed. (Refer to paragraph 4-240.)

NOTE

Check of fuel filters can be accomplished at start of engine run-up by observing for illumination of FUEL FILTER caution panel segments if filters are becoming clogged.

m. Open all circuit breakers and place all switches to OFF or normal positions at completion of checkout. n. Operational checkout of each pair of pilot-shutoff valve elements will be performed at start of each pressure fueling service by use of two test valve buttons in the fueling valve rim. As each button in turn is pressed and held in, the test valve will open and flood a float chamber in the pilot valve to simulate full-level condition and cause one element of shutoff valve to stop fuel flow into the system. When buttons are released, flow should resume until cells are full and both elements of shutoff valve close. 4-208. TROUBLESHOOTING. (Refer to table 4-1.)

CAUTION

Before troubleshooting malfunctions of pressure fueling subsystem, remove gravity fueling filler cap from right aft fuel cell to avoid hazard of pressure in event of overfilling and consequent damage to fuel cells and surrounding structure.

4-209. FUEL FILTERS. Two filters (3, figure 4-68), connected in the fuel pressure lines to engine power sections, are located on aft side of FS 166 bulkhead just above the engine deck at each side. Filter elements are replaceable type, and the filter heads incorporate electrical impending by-pass indicators connected to FUEL FILTER caution panel segments. Connections are provided for fuel inlet and outlet lines and for a drain line with a manual valve.


4-168

Figure 4-68. Fuel Supply System – Crashworthy Fuel System (Sheet 1 of 5)


4-169

Figure 4-68. Fuel Supply System – Crashworthy Fuel System (Sheet 2)


4-170



4-171



4-172



Change 6 4-173

4-210. REPLACING FILTER ELEMENTS. a. Open engine cowling. Refer to paragraph 4-152.

Aviation Turbine Fuel 2 b. Place container under the overboard fuel drain line. Open valve to drain fuel from filter. c. Open V-band clamp and remove filter body and element from filter head. d. Inspect element for contamination, observing for any unusual condition.

Drycleaning Solvent 7 e. Clean filter body mating surfaces of filter head with drycleaning solvent, MIL-PRF-680, Type II. Protect electrical connections during cleaning. f. Place new packing on boss in bottom of filter body, and insert new filter element to seal firmly on boss. g. Install new packings on upper end of filter body, and on center boss in filter head.

NOTE

When re-installing a used V-band clamp, check it for twist or distortion. Avoid twisting, spreading, or bending of the coupling when positioning the coupling on the joint. Couplings in poor condition should be replaced.

h. Close drain valve and install body and element assembly into filter head, pressing firmly into seat. Secure V-band clamp around mating flanges IAW NAVAIR 01-1A-8. While tapping outer circumference of V-band clamp, torque nut 50 inch-pounds. Lockwire clamp. (QA) i. At next operational checkout, checks for leaks at filter and that FUEL FILTER caution panel segment does not illuminate.

4-211. FUEL SHUTOFF VALVES. Two motor operated shutoff valves (6, figure 4-68), connected in fuel pressure lines to engine power sections, are located on the engine deck just aft of the pylon support. The valves are electrically controlled by the ENG 1 and ENG 2 FUEL CONT switches, and have manual override handles which also serve as position indicators. Thermal relief valves are incorporated in shutoff valves to allow internal by-pass of fuel trapped in outlet lines when system is inoperative. 4-212. REMOVAL. a. Remove door assembly for access to area behind pylon support. (Refer to NAVAIR 01-110HCE-2-1.) b. Disconnect electrical connector from valve.

Aviation Turbine Fuel 2 c. Disconnect fuel lines from tee fitting on forward side and from fitting on aft side of valve. Cap open lines. d. Remove four screws to detach valve from mounting bracket. e. If replacing valve, remove tee fitting and flange fitting. Cover openings. 4-213. INSTALLATION. a. If replacing valve, transfer tee fitting and outlet flange fitting to replacement valve. b. Position valve assembly on mounting bracket with outlet flange fitting forward. Install four screws with nuts and washers. Torque nuts 25 to 30 inch-pounds. (QA) c. Connect line from filter to valve outlet fitting, line from lower cell to inboard end of tee fitting, and line from interconnect valve to outboard end of tee fitting. d. Connect electrical connector to valve. e. At next operational checkout, check for proper operation and for leaks.


4-174 Change 6

4-214. SYSTEM INTERCONNECT VALVE. A motor operated ball valve (7, figure 4-68), connected to a crossfeed line between the fuel pressure lines to engine power sections, is located above the shutoff valves, aft of the pylon support. The valve has a position indicator and is controlled by a switch on the engine control panel. 4-215. REMOVAL. a. Remove door assembly for access to area behind pylon support. (Refer to NAVAIR 01-110HCE-2-1.) b. Disconnect electrical connector from valve.

Aviation Turbine Fuel 2 c. Disconnect fuel lines from valve connections. d. Remove four screws, with nuts and washers, to detach valve assembly from mounting bracket. e. If replacing valve, remove two connectors. 4-216. INSTALLATION. a. If replacing valve, transfer two connectors to replacement unit, using new packings. b. Position valve in mounting bracket and install four screws, with nuts and thin aluminum alloy washers. Torque nuts 25 to 30 inch-pounds. (QA) c. Connect fuel lines from outboard ends of shutoff valve tee fittings. d. Connect electrical connector to valve. e. At next operational checkout, check for proper operation and for leaks. 4-217. PRESSURE FUELING VALVE ASSEMBLY. The fueling valve for use with a pressure nozzle is

on the right side of the fuselage at Station 182.5 W.L. 29. The valve assembly has a standard cap, two test valves with external plungers for manual actuation, and elbow fittings for lines to the pilot valve, an outlet, and an adapter for hose connection, and a lower outlet closed by a capped adapter. 4-218. REMOVAL. a. Open fuselage door for access to pressure fueling valve (8, figure 4-69). b. Disconnect two test valve lines (21) from elbows (7) and tube (25) from adapter (14). c. Remove 16 screws (2) and washers to detach pressure fueling valve (8) from fuselage panel. Remove pressure fueling valve (8) and gasket (4). d. If replacing pressure fueling valve, remove cap (3) and fittings for use on replacement assembly. 4-219. INSTALLATION. a. When replacing pressure fueling valve, install elbow and adapter fittings as follows: 1. Assemble gasket (11, figure 4-69), and adapter (14) on inboard port of pressure fueling valve (8) with four bolts (13) and thin aluminum washers (12). Install bolts evenly. 2. Assemble gasket (19) and adapter (18) on lower port of valve with four bolts (16) and thin aluminum washers (17). Install cap (15) on adapter. 3. Install an elbow fitting (7) with nut (6) and packing (5) in each of two test valve ports on aft side of pressure fueling valve (8). Position open ends of elbow inboard before installing nuts. b. Place gasket (4) on mounting flange of pressure fueling valve. c. Position pressure fueling valve (8, figure 4-69) on inboard side of fuselage panel, with test valves aft and test valve plungers (20) inserted through holes provided. Align holes and install


Change 4 4-175

16 screws (2) from outboard side, with thin aluminum washers (1) under heads. Install screws evenly. d. Connect tube (25) (from shutoff valve on adapter (14)) on inboard end of pressure fueling valve. e. Connect test valve tubes (21) from center cell door to elbow fittings (7) on pressure fueling valve (8). f. Install cap (3) on pressure fueling valve (8). 4-220. PRESSURE FUELING PILOT VALVE. The dual float-actuated pilot valve of the pressure fueling subsystem is in the center aft fuel cell, on a support bracket attached to the cell door. The valve assembly contains two float chambers, and has connections for two lines from the test valves and two lines from the fuel shutoff valve. 4-221. REMOVAL. a. Remove access door from underside of fuselage. (Refer to NAVAIR 01-110HCE-2-1.) b. Defuel helicopter and remove access door assembly from center of aft fuel cell. (Refer to paragraph 4-226.)

Aviation Turbine Fuel 2 c. Disconnect four hoses (32, 45, 46 and 47, figure 4-69) from fittings on bottom of pilot valve (26). d. Detach valve from support by removing three screws (49) and washers (50). e. If replacing valve assembly, remove four fittings with packings. Install protective plugs or covers at valve ports. 4-222. INSTALLATION. a. If installing a replacement valve assembly, remove protective plugs and install four fittings with packings in ports on bottom of valve.

b. Align valve on support and install three screws (49, figure 4-69) with thin aluminum alloy washers (50). c. Connect four hoses (32, 45, 46 and 47) from inner side of door to fittings on valve. d. Install center cell door and attached parts. (Refer to paragraph 4-226.) e. During fueling, check for leaks and proper operation of system. f. Install access door on underside of fuselage. (Refer to NAVAIR 01-110HCE-2-1.) 4-223. PRESSURE FUELING SHUTOFF VALVE. The dual shutoff valve on the pressure fueling subsystem is mounted on brackets on aft side of Station 155.06 bulkhead, below WL 22 and slightly left of center. The valve assembly has an inlet elbow connected to the fueling valve, an outlet tee fitting connected in the fuel system aft interconnect line, and two elbows on right side for sensing lines to the pilot valve. 4-224. REMOVAL. a. Defuel helicopter until fuel level is below aft interconnect line. b. Remove access doors. c. Remove elevator control bellcrank (NAVAIR 01-110HCE-2-5) located to the right of shutoff valve (67, figure 4-69) on same level, for access through bulkhead.

Aviation Turbine Fuel 2 d. Disconnect two sensing lines (22, figure 4-69) from elbows on right side of valve, fuel line (23) from valve inlet flange elbow (63), and aft interconnect line hoses from couplings (24) at each side of valve outlet tee, using container to catch any spilled fuel.


4-176 Change 6

Figure 4-69. Pressure Fueling Provisions (Sheet 1 of 2)


Change 6 4-177

Figure 4-69. Pressure Fueling Provisions (Sheet 2)


4-178

e. Detach valve brackets from bulkhead by removing four bolts (70) and washers from forward side of bulkhead. f. Remove valve assembly through bulkhead opening where bellcrank was removed. g. If replacing valve, remove fittings and brackets for reuse. Install protective plugs or covers on valve openings. 4-225. INSTALLATION. a. When replacing valve (67, figure 4-69), install fittings and bracket as follows: 1. Assemble gasket (66), retainer (65), with groove up, packing (64), elbow (62) and flange (63) on valve inlet port. Align holes and install four bolts (60) with thin aluminum alloy washers (61). Align elbow approximately 45 degrees right and aft. 2. Install reducers (72) with packings (73) in two ports on side of valve assembly. Install a hose (22) on each reducer. Align elbows pointing approximately 45 degrees up and aft. 3. Install a coupling (24) with packing in each end of tee fitting. Assemble fitting (68) with packing on valve outlet, with index pin engaged. Position shortest bracket (71) on forward holes (as valve will be installed, with sensing line elbows at right) and install two bolts with thin aluminum alloy washers. Position longer bracket (69) on aft holes and install bolts and washers. b. Through access hole where bellcrank was removed, position valve assembly on aft side of bulkhead with brackets aligned to mounting holes. Install four bolts (70) with thin aluminum alloy washers from forward aide of bulkhead into nutplates of brackets. Torque bolts 20 to 25 inch-pounds. (QA) c. Connect hoses of aft interconnect line to couplings (24) on each side of valve outlet fitting. d. Connect line (23) from fueling valve to elbow on valve inlet.

e. Connect sensing lines (22) from center cell door to two elbows on right side of valve. f. During fueling, check for leaks and for proper operation of system. g. Reinstall elevator control bellcrank. (Refer to NAVAIR 01-110HCE-2-5.) h. Install access door. (Refer to NAVAIR 01-110HCE-2-1.) 4-226. AFT FUEL CELLS. Three aft fuel tank cells are located in fuselage compartment aft of the pylon support between the engine deck and cabin floor level. The center cell is inside the two BL 14 main structural beams, between bulkheads at Station 155 and 178. The left and right cells are outboard of the main beams, between Stations 166 and 178. Cells are self-sealing type, and cell openings for use with doors and fittings have crashworthy features. Foam baffles fill the cells in patterns of shaped blocks without significant reduction of tank capacity or fuel flow. Side cells have interconnection ports on bottom and lower inboard sides, and a vent port on the top. The upper side also has an access slit, sealed by a bolted doubler, for removal and installation of foam baffles. The right cell has a filler port. The center cell has interconnection ports on bottom and lower outboard sides, and a large access door opening on the aft side. The center cell access door provides mounting and electrical connections for the fuel quantity gage probe and for a pair of float switches used with auxiliary fuel tanks, inlet fittings and check valves for the engine governor bleed lines. The center cell access door also has a support for the pilot valve of the pressure fueling subsystem, and connections for its test and sensing lines. 4-227. REMOVAL. a. Disconnect battery and all external electrical power. Refer to NAVAIR 01-110HCE-2-11. b. Defuel and purge system, adhering strictly to instructions contained in NAVAIR 01-1A-35.


Change 4 4-179

NOTE

Depuddling procedures in NAVAIR 01-1A-35 cannot be accomplished until foam baffles have been removed from cells.

c. Remove power plant. Refer to paragraph 4-189. d. Remove access doors. (Refer to NAVAIR 01-110HCE-2-1.)

WARNING

Before starting removal of foam baffles from tank cells, personnel shall ground themselves to the aircraft to remove static electricity.

Aviation Turbine Fuel 2 e. Disconnect four hoses of pressure fueling test and sensing lines from check valves on center cell door. Disconnect and remove two AFCU bleed line tubes from check valves on cell door and from fittings under deck. (See figure 4-70.) Cap open fittings. Disconnect fuel quantity circuit leads from two connectors on door. Disconnect transfer pump circuit leads from terminal block, leaving float switch leads in place. f. Remove 24 bolts with washers around edge of door. Pull door aft and reach in through opening. Disconnect leads of fuel quantity probe (17, figure 4-68) from connectors on inside of door. Detach cable straps securing probe to upper and lower brackets. Push probe free of clips. Remove access door aft and downward. Remove bolts and washers to detach and remove compartment access door from bulkhead.

NOTE

Maintain a continuous air purge, once cell is opened, until all foam baffles are removed. Take special care to prevent contamination of foam baffles and cell.

Figure 4-70. Center Cell Access Door Connections

g. Using leather or rubber gloves, compress and remove foam baffles. (See figure 4-71.) Remove fuel quantity probe when clearance allows. If markings on baffles are not legible, identify for remarking after drying. h. Inspect, clean, dry, repair and restore markings, using felt tip pen, and store removed baffles in accordance with NAVAIR 01-1A-35. i. Inside center cells, remove bolts and washers from connector fittings at left and right sides. j. Disconnect and detach two outlet fittings on underside of center aft cell. 1. For additional access to forward right valve, remove elevator control bellcrank. (Refer to NAVAIR 01-110HCE-2-5.) 2. Disconnect crossover hoses (21, figure 4-68) from two valves (56) and cap hoses. 3. Remove each of two valves by loosening nut (57) and screwing valve from cell outlet fitting. 4. Detach each outlet fitting (55) from structure by removing two screws (49), leaving fittings attached to cell.


4-180

Figure 4-71. Foam Baffles in Center Aft Fuel Cell


4-181

k. Disconnect and detach vent fittings at top of center aft cell. 1. Remove screws from access plate on engine deck at left of driveshaft tunnel at approximately Station 173. Remove safety clip (45, figure 4-68) and detach cell support cable (46) from bracket on access plate. Remove plate. 2. Disconnect four vent hoses from elbows and tee on cover (10). 3. Remove 16 bolts (44) and washers to detach cover from cell. Remove cover assembly and packing.

CAUTION

Do not allow a fuel cell to remain folded more than 30 minutes before restoring to normal shape. Prolonged folding may damage cell.

l. Compress and fold center cell as shown in figure 4-72, tying with clean nylon straps. Remove cell from compartment. m. When replacing cell, remove each of two outlet fittings (55, figure 4-68) and packings from bottom of cell by removing four countersunk screws (48).

NOTE

Removal of left or right aft cells, by the following steps, are alike except for filler assembly and single crossover hose connection on right cell.

n. Disconnect and detach outlet fitting on underside of left or right aft cell: 1. Disconnect crossover hose (21) from interconnect fitting. Cap hose. 2. Loosen nut and screw interconnect valve (50) from cell outlet fitting.

3. Detach outlet fitting (47) from structure by removing two screws (49), leaving fitting attached to cell. o. Remove main fuel filter, throttle control torque tube and idle stop solenoid for clearance in removing cell. p. Remove attaching screws and deck panel above cell. q. Disconnect and remove vent hose from elbow on cell cover (5). r. Remove 16 bolts (43) and washers, cover and packing from top cell. s. Using leather or rubber gloves, remove foam baffles. (See figures 4-73 and 4-74.) If markings on baffle are not legible, identify for remarking after drying. t. Inspect, clean, dry, repair and restore markings, and store removed baffles in accordance with NAVAIR 01-1A-35. u. On right cell only, remove 14 screws (38, figure 4-68) and washers, retainer (39), filler cap and adapter (40), and packing, leaving spacer (41) attached to cell until after removal.

CAUTION

Do not allow a fuel cell to remain folded more than 30 minutes before restoring to normal shape. Prolonged folding may damage cell.

v. Collapse cell as shown in figure 4-72, tying with clean nylon straps. Remove cell from compartment. w. When replacing cell, remove outlet fitting by removing four countersunk screws (48, figure 4-68). On right fuel cell, also remove 13 countersunk screws (42) to remove spacer and packing from filler opening.


4-182

Figure 4-72. Folding Fuel Cells For Removal or Installation (Sheet 1 of 3)


4-183

Figure 4-72. Folding Fuel Cells For Removal or Installation (Sheet 2)


4-184

Figure 4-72. Folding Fuel Cells For Removal or Installation (Sheet 3)


4-185

Figure 4-73. Foam Baffles in Left Aft Fuel Cell


4-186

Figure 4-74. Foam Baffles in Right Aft Fuel Cell


Change 4 4-187

4-228. INSTALLATION a. Inspect fuel cell compartments, for cleanli-ness and smooth condition of interior surfaces.

NOTE

Installation of right or left cells, by the following steps, are alike except for filler assembly and single crossover hose connection on right cell.

b. Place new packing in groove around outlet port on bottom of right or left cell. Install outlet fitting (47, figure 4-68) with four countersunk screws (48). Torque screws 50 to 70 inch-pounds. (QA) c. On right cell, place new packing in groove around filler port. Install spacer with 13 countersunk screws (42). Torque screws 50 to 70 inch-pounds. (QA)

Adhesive 13 d. Collapse right or left cell as shown in figure 4-72, tying with clean nylon straps. Install a packing in groove around cell crossfeed port on inboard side, using a suitable adhesive (CAGE 91427) or equal to hold packing in place. Place cell into fuselage compartment. Remove straps and restore cell to normal shape. e. On right cell, place packing in groove around spacer (41, figure 4-68) at port. Assemble filler cap and adapter (40) and retainer (39) to spacer (41) from outer side of skin panel, with straight edge at top and with riveted ground strip aligned with an upper bolt hole. Install 14 screws (38) with thin aluminum washers. Torque screws 50 to 70 inch-pounds. (QA) f. Align outlet fitting (47) on bottom of right or left cell with hole in structural panel, and install two screws (49). Torque screws 50 to 70 inch-pounds. (QA)

g. Assemble nut and packing on inter-connect fitting and install into outlet fitting on left or right cell. Connect crossover hose (21) from forward cell to nipple on interconnect (50). On right cell interconnect, install plate and packing with four screws and thin aluminum alloy washers on port at right side. On left cell interconnect, install packing and flange of crossover hose (21) from center cell in like manner. h. Install an outlet fitting (55) with packing and four countersunk screws (48) on each of two outlet ports on bottom of center aft cell. i. Collapse and fold center cell as shown in figure 4-72, tying with nylon straps. Install a packing with suitable adhesive No. 4 (CAGE 91427) or equal in groove around each cell crossfeed port on left and right sides of cell. Carefully insert cell into compartment, remove straps and unfold to normal shape. j. Check that packings are in place on crossfeed ports of center cell and mating ports of right and left cells. Align each pair of ports to mounting holes of BL 14 beams, and install four bolts with thin aluminum alloy washers, from inside center cell at each side. Torque bolts 120 to 130 inch-pounds. (QA) k. Assemble nut (57, figure 4-68) and washer on each of two crashworthy interconnect valves, and install into two outlet fittings (55) on bottom of center cell. Connect hose from aft interconnect line (37) to right forward valve. Connect crossover hose (21) from left cell interconnect fitting to left aft valve.

CAUTION

Correct positioning of baffles is extremely important. Designed voids in foam baffles shall maintain required clearances around all fuel system components, vents and fuel inter-connects.


4-188 Change 6

I. Prior to fuel cell foam installation, visually inspect fuel cell interior for evidence of contamination. Pay particular attention to the interface between the fuel cell fittings and the fuel cell. If necessary, wipe interior fuel cell surfaces with clean, lint free rags. m. Visually inspect fuel cell foam for surface deterioration prior to installation. Surface deterioration is detected by a loss of tensile properties, cracking, breaking, or crumbling of fuel foam material. Discoloration due to exposure to ultraviolet light is normal and is not necessarily cause for rejection. n. Install foam baffles into left and right aft cells through top opening. (See figures 4-73 and 4-74.) o. Install each left and right cell cover (5, figure 4-68) with packing and 16 bolts (43) with thin aluminum alloy washers, aligning vent elbow to point inboard. Torque bolts 50 to 70 inch-pounds. (QA) p. Install cover (10) on center aft cell with packing and 16 bolts (44) with thin aluminum alloy washers, aligning vent tee at forward side with ends pointing outboard. Torque bolts 50 to 70 inch-pounds. (QA) q. Connect vent hose from left cell elbow to left end of center cell tee, and hose from right cell elbow to elbow on right side of center cell cover, using rubber grommets where hoses pass through BL 14 beam. r. Connect forward cells vent line hose from elbow under deck to right end of center cell vent tee. s. Prior to fuel cell foam installation, visually inspect fuel cell interior for evidence of contamination. Pay particular attention to the interface between the fuel cell fittings and the fuel cell. If necessary, wipe interior fuel cell surfaces with clean, lint free rags. t. Visually inspect fuel cell foam for surface deterioration prior to installation. Surface

deterioration is detected by a loss of tensile properties, cracking, breaking, or crumbling of fuel foam material. Discoloration due to expo-sure to ultraviolet light is normal and is not necessarily cause for rejection. u. Connect overboard vent line hose from union on Station 178 bulkhead to elbow at left aft on center cell cover. v. Position access door above deck opening. Engage ball terminal of center cell support cable (46) in slot of bracket on underside of door, and secure with safety clip (45) through bracket. Install door with screws. w. Install foam baffles into center cell through access ports. (See figure 4-71.) Place quantity gage probe (17, figure 4-68) vertically in recess provided in baffles. Position shaped baffle between brackets on door (16). x. Install access panel on aft side of Station 178 bulkhead. y. Place packing in groove around center cell access port. Hold door assembly near opening, with brackets, extending into cell. Position quantity gage probe in support clips and secure with cable straps. Connect probe electrical leads to connectors on inside of door. Align door to mounting holes and install 24 bolts with thin aluminum alloy washers and four retainers. (See figure 4-70.) Torque bolts 50 to 70 inch-pounds. (QA)

CAUTION

In the following step, ensure that all check valves on center cell access door are installed with flow arrows forward, towards the front of the fuel cell (away from the cell access door).

z. Connect two AFCU bleed line tubes from fittings under deck to check valves on center cell access door. (See figure 4-70.) Also connect hoses of two pressure fueling sensing and two test valve lines as shown. Connect quantity gage circuit leads to connectors, and auxiliary fuel transfer circuit leads to terminal block on door.



Corrosion Inhibitive Sealing and Coating Compound 22

Sealing Compound 8 aa. When fire resistant hose assemblies are replaced, apply a bead of sealing compound, MIL-PRF-81733, Type II-1/2 or AMS-S-8802, Type B, Class 2, at juncture of fittings and firesleeve.

ab. Install deck panels above left and right aft cells. ac. If facilities are available, pressure test fuel cell installation at 2.5 to 2.75 psig with main fuel line and vent connections capped. Cells should hold initial pressure for 15 minutes. Locate and correct any leaks before proceeding. (QA) ad. Flush fuel system as required by NAVAIR 01-1A-35. Service system and check for leaks. ae. Install throttle control torque tube, idle stop solenoid, fuel filter and elevator control bellcrank if removed for access. Install access doors. af. After installation of power plant, perform operational check of fuel system. (Refer to paragraph 4-207.)


Change 4 4-189

4-229. FORWARD FUEL CELLS. Two fuel tank cells are located under the cabin floor outboard of BL 14 main longitudinal beams, between fuselage stations 102 and 155. Cells are laminated fabric and rubber self-sealing type, with molded-type metal fittings at openings, and are filled with foam baffles in patterns of shaped blocks with recesses and passages for internal components and hoses. Each cell has a vent port on the upper inboard side, interconnection ports on forward and aft ends, a drain port and a large opening for the sump assembly on the lower side. A baffle divides each cell into forward and aft compartments has a directional flow flapper valve. The sump opening provides access to the aft compartment. A cover provides access to the forward compartment. The right-hand cell has threaded inserts on its inboard wall for attachment of two fuel quantity gage probes. Each sump assembly (figure 4-75) is equipped with an electrically operated boost pump, an outlet cross-fitting, a check valve, a flow-actuated switch and each sump assembly has a defueling valve (35, figure 4-68) which can be used by removing a plug and installing a standard fitting (MS33656E12). The left cell sump also has a low-level float switch. The right cell sump has connectors for the fuel quantity gage probes. A vent line is attached to each cell through a breakaway self-closing valve assembly (33, figure 4-68). Sump and aft outlet fitting are secured to compartment structure only by retainers (36) which are designed to breakaway in a crash impact. Flapper (swing check) valve (28) in baffle between cell compartments is removable without requiring access to forward compartment. A wire cover is installed on bottom of each sump. 4-230. REMOVAL – FORWARD FUEL CELL SUMP ASSEMBLY. a. Disconnect all electrical power. Defuel system. b. Remove sump access panel from lower skin of fuselage.


c. Drain sump through valve (27, figure 4-68). d. Detach wire cover from sump by removing three bolts with washers. Disconnect electrical leads of pump and other units at terminal block. On right cell, disconnect quantity gage circuit leads from connectors on sump (25). e. Remove 21 screws with washers and four retainers (36). Lower sump assembly a few inches, reach through opening, and disconnect hoses from fittings on flow switch (26) and on pump outlet cross fitting. On right cell, disconnect quantity gage probe (34) leads from connectors on sump plate. f. Remove sump assembly and packing. Cover cell opening. 4-231. REPLACING FUEL BOOST PUMP. (See figure 4-75.)

WARNING

If installing the cartridge type fuel boost pump assy, ensure spring end of shutoff valve lever arm is fully depressed prior to installation of negative terminal and shoulder screw. (See para 4-232.)

a. Remove 12 bolts (16) and washers (15) to detach pump (24) and gasket (14) from sump plate. b. Transfer plug (18) to replacement pump, using new packings (17). c. Remove bolt (20) to detach cross fitting (29) and plug (22) from pump outlet port. Check that cross fitting is clean and unobstructed. Install fitting (29), plug (22), bolt (20) and washer (19) with new packings in replacement pump. Install bolt, but omit Iockwire until hoses are reconnected. (QA) d. Assemble pump assembly (24) with gasket (14) to sump plate with mounting bolts (16) and thin aluminum alloy washers (15). Torque bolts 50 to 70 inch-pounds. (QA)


4-190

Figure 4-75. Forward Fuel Cell Sump Assemblies (Sheet 1 of 3)


4-191

Figure 4-75. Forward Fuel Cell Sump Assemblies (Sheet 2)


4-192

Figure 4-75. Forward Fuel Cell Sump Assemblies (Sheet 3)


Change 4 4-193

4-232. REPLACING CARTRIDGE (2C27-3). (See figure 4-75.)

WARNING

Personnel shall observe all safety precautions while engaged in fuel system maintenance.

NOTE

Removal and installation procedures for both fuel boost pump cartridges are identical.

a. Disconnect positive electrical lead (59) from boost pump (24). b. Cut Iockwire on screw (60), drain plug receiver (61) and drain plug (18). c. Remove screw (60) and shutoff lever (62). Turn shutoff lever (62) 90 degrees counter-clockwise and move negative electrical lead (63) away from boost pump (24). d. Remove retaining ring (64). e. Remove drain plug (18).

Aviation Turbine Fuel 2 f. Install slide hammer in drain hole and remove cartridge (58) from canister. Discard packings. g. Clean cartridge cavity with wiping rag.

CAUTION

Do not force cartridge into canister. Eccentric cartridge design requires alignment arrows to be within ±3 degrees for proper alignment.

h. Lubricate three packings with aviation fuel JP-4 and install on cartridge (58). Insert cartridge (58) into canister with arrows aligned.

i. Install retaining ring (64). j. Install drain plug (18).

WARNING

Do not apply pressure to the free end of the fuel boost pump shutoff lever arm (62). This may cause binding of the shutoff valve and bending of the lever arm, resulting in the restriction of fuel flow and possible flameout. Ensure the spring end of the shutoff lever arm is fully depressed prior to the installation of the grounding terminal (63) and screw (60).

k. Position the slotted end of fuel shutoff lever (62) over the negative terminal hole on the fuel boost pump cartridge face. Keeping the spring end of the shutoff valve lever arm (62) fully depressed, connect the negative lead terminal (63) using the shoulder screw (60). Fuel shutoff valve lever arm should be approximately horizontal across the cartridge face and boost pump shutoff valve boss. Lockwire screw (60), and drain plug (18) to drain plug receiver (61). (QA) I. Connect positive electrical lead (59). m. Perform operational check. 4-233. REPLACING FLOW SWITCH. (See figure 4-75.) a. Remove nut (25) and washer (26) from underside of sump plate to detach flow switch (3). b. Transfer check valve (46) and union (45) to replacement switch using new packings. c. Assemble switch to sump plate with a new packing installed on electrical outlet of switch. Secure with nut (25) and washer (26). Torque 40 to 50 inch-pounds and Iockwire. (QA) 4-234. REPLACING FLOAT SWITCH. (See figure 4-75.) a. To replace switch (5) only: Loosen and remove switch and packing (7) from support (8).


4-194 Change 6

Place packing on replacement switch; thread wires through support; start and install switch. b. To replace support: Remove nut (30), washer (31) and packing (43) from underside of sump plate. Remove support (8) and switch assembly (5). Transfer switch to replacement support. Assemble support to sump plate with nut (30), washer (31) and new packing (43). Torque nut not more than 25 inch-pounds. (QA) 4-235. REPLACING SUMP DRAIN VALVE. (See figure 4-75.) a. Remove two screws (33), nuts (41), washers (40) and seal washers (39) to detach drain valve (38) and retainer (42) from sump plate. b. Assemble replacement valve (38) with new packing (37) to lower side of sump plate, and retainer (42) to upperside. Align holes and install two screws (33) with washers (40) and seal washers (39) and nuts (41). Torque nuts 25 to 30 inch-pounds. (QA) 4-236. INSTALLATION – FORWARD FUEL CELL SUMP ASSEMBLY. a. Place new packing in groove around cell port. b. Position sump assembly (25, figure 4-68) slightly below cell port. Reach through opening to connect hose between outboard nipple of pump outlet cross fitting and check valve on inlet of flow switch (26). Connect hoses to inboard nipples of flow switch and cross fitting. On right cell, connect quantity gage probe (34) leads to connectors on sump plate. c. Lift sump assembly (25) to position. Install 21 screws with thin aluminum alloy washers and four retainers (36) in forward outboard quadrant and two in aft quadrant. Attach grounding jumper from structure to a screw on sump. Torque screws 50 to 70 inch-pounds. (QA) d. Connect electrical leads to terminal block. On right cell, connect quantity gage circuit leads to sump plate connectors. Install wire cover with three bolts and thin aluminum alloy washers.

e. Check for leaks during operational check. 4-237. REMOVAL – FORWARD FUEL CELLS. a. Disconnect battery and all external elec-trical power. Refer to NAVAIR 01-110HCE-2-11. b. Defuel and purge system, adhering strictly to instructions contained in NAVAIR 01-1A-35.

NOTE

Depuddling procedures in NAVAIR 01-1A-35 cannot be accomplished until foam baffles have been removed from cells.

c. Remove forward cell sump assembly. (Refer to paragraph 4-230.)

WARNING

Before starting removal of foam baffles from tank cells, personnel shall ground themselves to the aircraft to removed static electricity.


NOTE

Maintain a continuous air purge, once cell is opened, until all foam baffles are removed. Take special care to prevent contamination of foam baffles and cell.

d. Using leather or rubber gloves, compress and remove foam baffles from aft compartment of cell. (See figure 4-76.) If markings on baffles are not legible, identify for remarking after drying. e. Remove floor panels over cell com-partment. (Refer to NAVAIR 01-110HCE-2-1.)



f. Remove cover (29, figure 4-68) from forward compartment of cell with 16 screws and packing. Remove foam baffles. (See figure 4-76.) g. Inspect, clean, dry, repair and restore markings, and store removed baffles according to NAVAIR 01-1A-35.

h. Disconnect vent line hose from vent valve (33, figure 4-68). Cap hose end. Detach valve from structure by removing nut and washer. Detach valve and packing from cell by removing two bolts and washers.


4-195

i. Disconnect main fuel hose, aft interconnect line hose (37, figure 4-68) and crossover hose from fittings on cell outlet fitting on aft side of FS 155 bulkhead. Remove six bolts (54) and washers to detach outlet fitting (52) and retainer (53) from cell. Pull outlet fitting aft to disconnect hose from check valve (22) on inside face. Remove fitting assembly and packing. j. Disconnect hoses from ejector pump (32) and from union (63) at flapper valve plate on baffle. Detach hose from inboard wall of cell by removing bolts at clamps, on right cell, detach and remove two quantity gage probes (34). k. Remove ejector pump (32) and support by removing two bolts (71) to detach support from bottom of cell. l. Detach forward interconnect fitting from front end of cell by removing nut (72) and packing inside cell. Pull fitting out of cell port. m. Remove retainer with two attached clips from drain valve (30) by removing two screws (65) which attach clips to cell. Remove nut (67) from inner end of valve, and remove valve with packing. Remove two bolts (68) and washers adjacent to cell port. n. Lift cell from compartment. o. If cell is to be replaced, remove flapper valve and plate assembly from lateral baffle in cell. 4-238. INSTALLATION. a. If flapper valve (28, figure 4-68) was removed, install as follows: 1. Assemble drilled plate (61) on aft side of lateral baffle, and plate (62) with two nutplates on forward side. Align holes and install three bolts (64) from forward side, with aluminum alloy washers under nuts. 2. Position swing check valve (59) on aft plate. Install two screws (58) with thin aluminum alloy washers. 3. Install union (63) from aft side, secured by nut (60). Connect hoses to union.

b. Inspect cell compartment for cleanliness and smoothness of inner surfaces. Place cell in compartment. c. Align forward drain port with mounting hose in structure. Install two bolts with special washers from lower side into cell inserts. Torque bolts so 50 to 70 inch-pounds. (QA) d. Insert forward drain valve (30) from below, and secure with nut (67) inside cell. Place retainer (66) with two attached clips over nut. Install two screws, with thin aluminum alloy washers, through ends of clips into inserts in cell. Safety valve closed with 0.032 lockwire. (QA) e. Check that vapor seal (73), large washer (74), and clamp (76) are in place on hose of forward interconnect line (31). Place packing on end fitting and insert through port at front of cell. Install nut (72), on fitting inside cell. Adjust clamp (76) to hold vapor seal against bulkhead. f. Position ejector pump (32) with attached support in forward end of cell, with support under interconnect fitting. Install two bolts, with thin aluminum alloy washers under heads, through support into cell inserts. Torque bolts 20 to 25 inch-pounds. Connect hoses to pump inlet and outlet. (QA) g. Insert vent valve (33) with packing into vent port of cell, and install two bolts with thin aluminum alloy washers. Torque bolts 50 to 70 inch-pounds. Insert valve fitting through hole in BL 14 beam and secure with washer and nut. Connect vent line hose. (QA) h. In right cell only, install quantity gage probes (34): 1. In forward compartment, align clamps on probes with spacers to inserts on inboard cell wall and install bolts. Pick up clamp on ejector pump outlet hose on upper probe clamp bolt. 2. In aft compartment, attach a clip with screw, washer and nut on lower clamp of probe. Align clip and upper clamp to spacers and cell inserts, and install bolts.


4-196

Figure 4-76. Foam Baffles in Forward Fuel Cells (Sheet 1 of 2)


4-197

Figure 4-76. Foam Baffles in Forward Fuel Cells (Sheet 2)


4-198 Change 5

i. Route free end of ejector outlet hose over inboard end of fabric baffle. Attach clamp on hose with screw and thin aluminum alloy washer to insert at top of cell near vent port.

CAUTION

Assure check valve (22, figure 4-68) is installed in direction of arrow stamped on valve.

j. Connect booster pump outlet hose to check valve (22) on inner side of aft outlet fitting. Place packing in groove around outlet port. Align outlet fitting (52) with straight edge down, and retainer (53) to port and install six bolts (54) with thin aluminum alloy washers. Torque bolts 120 to 130 inch-pounds. Connect crossover hose, main fuel line hose, and aft interconnect line hose to fittings on cell outlet fitting. (QA)

Corrosion Inhibitive Sealing and Coating Compound 22

Sealing Compound 8 k. When fire resistant hose assemblies are replaced, apply a bead of sealing compound, MIL-PRF-81733, Type II 1/2 or AMS-S-8802, Type B, Class 2, at juncture of fittings and firesleeve. I. Prior to fuel cell foam installation, visually inspect fuel cell interior for evidence of contamination. Pay particular attention to the interface between the fuel cell fittings and the fuel cell. If necessary, wipe interior fuel cell surfaces with clean, lint free rags. m. Visually inspect fuel cell foam for surface deterioration prior to installation. Surface deterioration is detected by a loss of tensile properties, cracking, breaking, or crumbling of fuel foam material. Discoloration due to exposure to ultraviolet light is normal and is not necessarily cause for rejection. n. Install foam baffles in forward compart-ment. (See figure 4-76.) Install cover (29, figure

4-68) with packing and 16 screws. Torque screws 50 to 70 inch-pounds. (QA) o. Install foam baffles in aft compartment. (See figure 4-76.) Install sump assembly. (Refer to paragraph 4-236.) p. Install floor panels over cell. q. If facilities are available, pressure test fuel cell installation at 2.5 to 2.75 psig with main fuel line and vent connections capped. Cells should hold initial pressure for 15 minutes. Locate and correct any leaks before proceeding. (QA) r. Install floor panel over fuel cell. s. Flush fuel system as required by NAVAIR 01-1A-35. t. Perform operational check of fuel system. 4-239. AUXILIARY FUEL SYSTEM. 4-240. OPERATIONAL CHECKOUT. a. Open AUX FUEL TRANS and MASTER CAUTION LTS circuit breakers. Place BATTERY switch and both INT AUX FUEL TRANS PUMP switches OFF. b. Before servicing auxiliary fuel tanks, check operation of float switch and caution panel circuit: 1. Place BATTERY switch ON. Close MASTER CAUTION LTS circuit breaker. AUX FUEL LOW caution panel should be unlighted. 2. Place RH INT AUX FUEL TRAINS PUMP switch to ON. AUX FUEL LOW caution panel should be illuminated. Return switch to OFF and check that caution panel extinguishes. 3. Repeat step 2. using LH INT AUX FUEL TRANS PUMP switch. 4. Place BATTERY switch to OFF. c. After servicing auxiliary fuel tanks, check operation of fuel transfer to main fuel system:

NOTE

Main fuel system must be 1100 pounds, or below, to allow operation of fuel transfer pumps.

1. Place BATTERY switch ON. Check that MASTER CAUTION LTS circuit breaker is closed and that AUX FUEL LOW caution panel is


Change 2 4-199

unlighted. Place RH AUX FUEL TRANS PUMP switch to ON, then OFF; then operate LH switch in same manner. Observe that caution panel segment remains unlighted. 2. Place NON ESS BUS switch to MANUAL. Close AUX FUEL circuit breaker. 3. Place RH AUX FUEL TRANS PUMP switch ON. Check that pump is running in right-hand auxiliary tank. Return switch to OFF. 4. Place LH AUX FUEL TRANS PUMP switch ON. Check that pump is running in left-hand auxiliary tank. 5. Place RH AUX FUEL TRANS PUMP switch ON, and allow both pumps to run. 6. Place INVERTER switch to MAIN. Close FUEL QTY circuit breaker. Monitor fuel quantity gage. When main system is filled, fuel transfer relay should be actuated by upper float switch in aft center fuel cell and both pumps in auxiliary tanks should stop operating.

NOTE

The fuel level in main tank should not be lowered, without any interruption of electrical power or change of switch settings in auxiliary fuel system circuits, both pumps should automatically resume operations when dropping fuel level opens lower float switch, deenergizing fuel transfer relay to restore power to pump circuits. This portion of the operating cycle will normally be checked during ground run-up or test flight.

7. Position all switches to OFF or NORMAL. Open all circuit breakers. 8. Fill auxiliary tanks as required. 4-241. TROUBLESHOOTING. (Refer to table 4-1.) 4-242. INSTALLATION. a. Auxiliary fuel cells hose assemblies are not life limited, and require on-condition inspec-tion for leakage, wear, chafing, broken wire braiding, or corrosion lAW NA 01-1A-20 prior to installation of auxiliary fuel cells.

b. Remove troop seat and litter attachment fittings from cabin aft bulkhead and sides of pylon support structure.

CAUTION

If fuel line floor attachment fitting is allowed to turn during installation, twisting and cracking of fuel line may occur below floor level.

c. Install attachment fittings for each auxiliary fuel tank in mounting hole provided at locations indicated. (See figure 4-77.) Use thin aluminum alloy washers on each stud or bolt, and torque 50 to 70 inch-pounds. (QA) 1. Studs for tank straps in nine holes near outboard edge of aft bulkhead, and in nine holes near forward edge of pylon support wall (BL 14 beam). Use long stud in third hole above floor in pylon support and replace door guide screws with long studs. 2. Eyebolt in hole near top of aft bulkhead, at BL 29.65. 3. Eyebolt replacing attachment screw in upper aft corner of upper pylon access door. 4. Hook with spacer, washer and bolt in hole in cabin ceiling at FS 142.68 and BL 30-54 (above tank filler cap). d. Install filler cap and adapter assembly. (See figure 4-77.) 1. Install preformed packings on filler cap and adapter assembly (1). 2. Position filler cap and adapter in opening in fuel cell (2). 3. Secure cap and adapter assembly and support (3) to fuel tank with five bolts (4) and two eyebolts (5) with a thin washer under each bolthead. 4. Put 10 gallons of fuel in auxiliary fuel cell and perform operational check. Check for leaks around boost pump and fittings. (QA)


4-200

Figure 4-77. Auxiliary Fuel Tank Installation


Change 2 4-200A/(4-200B Blank)

KEY TO FIGURE 4-77

1 FILLER CAP AND ADAPTER 20 NUT 2 FUEL CELL 21 PACKING 3 GROUND JACK AND SUPPORT 22 NUT 4 BOLT 23 ELBOW 5 EYE BOLTS 24 PACKING 6 PUMP ASSEMBLY 25 HOSE 7 NUT 26 COUPLING HALF 8 VALVE VENT 27 PACKING 9 PACKING 28 CHECK VALVE 10 UNION 29 PACKING 11 PREFORMED PACKING 30 ELBOW 12 HOSE 31 ELBOW 13 COUPLING HALF 32 PACKING 14 NUT 33 COUPLING 15 ELBOW 34 HOSE 16 PACKING 35 COUPLING HALF 17 HOSE ASSEMBLY 36 CABLE 18 DRAIN VALVE 37 CLAMPS 19 ELBOW


Change 2 4-201

4-243. PRELIMINARY AUTOMATIC (AFCU) TO MANUAL FUEL CONTROL (MFCU) RIGGING.

CAUTION

Assure interconnect linkage is not bent and collective pitch control system rigging has been accomplished prior to performing this procedure.

NOTE

Due to many variables encountered in airframe and engine control rigging, the airframe linkage should be disconnected from the engine fuel controls during the following rigging procedures.

a. Rotate MFCU arm (2, figure 4-78) until MFCU min stop screw (16) contacts MFCU stop (1). MFCU pointer should indicate 0 degrees +/-1/16 inch. If pointer does not indicate within 1/16 inch of 0 degrees, adjust quadrant plate (17) by loosening mounting screws and rotating plate. If adjustment of quadrant plate (17) does not bring pointer within 1/16 inch of 0 degrees, check for a bent pointer.

CAUTION

Under no circumstances should MFCU min stop screw (16) be adjusted.

NOTE

Assure position of AFCU Ng stop screw is approximately neutral (equal number of screw threads visible above AFCU arm as below).

b. Rotate AFCU arm (8) until AFCU Ng stop screw (9) contacts AFCU stop (14) (trim stop stowed). Adjust interconnect linkage nut (12) until MFCU pointer indicates 90 degrees to 1/16 inch past 90 degrees. To adjust nut (12) depress interconnect spring (18) to release spacer (11) from nut (12). Check that a clearance of 0.030 to

0.040 inch exists between MFCU max stop screw (10) and MFCU stop (1). Adjust the MFCU max stop screw (10) as necessary to obtain this clearance. Tighten and secure stop screw (10) with Iockwire MS9226-01. 4-244. DELETED. 4-245. RIGGING POWER LEVER CONTROLS.

NOTE

Before rigging power lever control system, throttle control grips on collective control sticks shall be properly interconnected. (Refer to NA 01-110HCE-2-5.)

Prior to performing the following procedure, ensure Preliminary Automatic to Manual Fuel Control rigging has been accomplished (paragraph 4-243).

a. Check that levers (19 and 32, figure 4-34) are correctly located on control shafts of manual fuel control units (20 and 33). On left-hand engine, lever will be forward and approximately 15 degrees clockwise from center-line of stop arm. On right-hand engine, lever will be aft and approximately 15 degrees clockwise from center-line of stop arm. (See figure 4-79.) One serration equates to 15 degrees. b. Check that lower ends of control tubes (13 and 25, figure 4-34) are attached in center holes of levers on jackshaft (12).

CAUTION

Assure that bolt in upper end of control tube (25) is installed with bolthead outboard. (See view A.) Bolt installed in wrong direction can interfere with elevator control linkage.

c. Disconnect aft ends of tubes (10 and 11) from lower arms of jackshaft (12).


4-202 Change 2

Figure 4-78. Part Power Trim Stop (Sheet 1 of 2)


Change 2 4-203

Figure 4-78. Part Power Trim Stop (Sheet 2)


4-204 Change 4

d. Actuate IDLE STOP REL switch (1) to ENG 1 to retract solenoid (24). Rotate lever (19) on left-hand fuel control unit full travel both directions, visually checking that stop screws contact stop at max. power (90 degrees plus) and full off (0 degree) positions. If necessary to obtain stop contact, adjust control tube (15). Check for ease of rotation and interference's. e. Actuate IDLE STOP REL switch to ENG 2 to retract solenoid (34). Perform step d. with lever (32) on righthand fuel control unit. if necessary, adjust tube (30). f. Rotate ENGINE 1 and 2 throttles through full range; if binding exists, disconnect tubes (5 and 6) from bellcranks (7) at Station 94 to 95. Move tubes (10 and 11) back and forth to check for ease of movement and full travel. If binding exists, replace defective bellcrank or control tube; if not, reconnect tube (5 and 6) to bellcranks (7) and secure with attaching hardware. Check twist grip for freedom of operation.

NOTE

If binding or malfunction occurs in control stick and jackshaft assembly, check gear sectors for proper engagement and backlash. (Refer to NAVAIR 01-110HCE-2-5.)

g. Reconnect tubes (10 and 11) to lower arms of jackshaft (12) and secure with attaching hardware. h. Rotate ENG 1 throttle grip to full INCREASE. Twist grip should rotate 4 to 6 degrees additional after stop on automatic fuel control makes contact. Actuate IDLE STOP REL switch (1) to ENG 1, rotate and twist grip to full off. Check for 4 to 6 degrees overtravel of grip after fuel control stop makes contact. Adjust control tube (10) as necessary to balance grip overtravel between full INCREASE and off positions and secure with attaching hardware. Check full travel with collective full down and full up. If fuel control arm does not have enough travel, move lower end of tube (13) to next hole nearer end of arm on jackshaft (12). If condition of too much travel exists, move end of tube to next hole nearer jackshaft. Secure control tube (13) with attaching hardware.

NOTE

To increase amount of cushion, move tubes (13) or (25) outboard (FWD) from jackshaft. To decrease amount of cushion, move tubes (13) or (25) inboard (AFT) from jackshaft.

i. Repeat step h. for ENGINE 2 throttle grip (3, figure 4-34) making adjustment to balance overtravel with tube (11). Corrections of total travel can be made by moving lower end of tube (25) to appropriate hole in arm of jackshaft (12). Secure control tube (11) and (25) with attaching hardware. j. Rotate ENGINE 1 and 2 throttles open until Ng stop screw (9, figure 4-78) contacts AFCU stop (14). Check that MFCU pointer indicates a minimum of 90 degrees to 1/16 inch past 90 degrees. Also verify clearance between MFCU max stop screw (10) and MFCU stop (1) is 0.030 to 0.040 inch. Rotate ENGINE 1 and 2 throttles full closed until MFCU min stop screw (16) contacts MFCU stop (1). Check that MFCU pointer indicates 0 degrees +/- 1/16 inch. If these limits are not confirmed, recheck Power Lever Control Rigging (paragraph 4-245). k. Check each rodend and joint of linkage for security. (QA)

Figure 4-79. Location of Levers on Manual

Fuel Control


Change 4 4-205

l. Accomplishment of maximum gas generator speed (Ng) and manual-automatic interconnect linkage adjustment, paragraph 4-247, is required after complying with the preceding steps. 4-246. RIGGING – DROOP COMPENSATOR CONTROLS. (Figure 4-39.) a. Assure that collective pitch control system rigging has been accomplished. Nominal lengths are shown on illustration.

NOTE

Rig on pilot side only. b. Check that each lever (14 and 17) is properly installed on control shaft of power turbine governor (15 and 18). Center-line of lever should be 15 degrees clockwise from center-line of governor stop arm, viewed from left (detail A). One serration equates to 15 degrees. c. Check that adjustable tube (13) is approximately same length as nonadjustable tube (16). Begin with tube (13) attached at middle hole of arm on jackshaft (12). d. Disconnect actuator (10) from lower arm of torque tube (12). e. Disconnect control tube (6) from bellcrank of cambox (9). f. Check that long arm of cambox bellcrank is attached approximately in middle of adjust-ment slot of cam. (See detail B.) g. Use RPM INCR-DECR switch on collective stick to operate actuator. Check that actuator is adjusted for total stroke of approximately 5/8 inch from full extend (DECR) to full retract (INCR) positions. Center actuator at middle travel. Adjust stroke as required by means of screw and Iocknut below actuator rod, turning screw clockwise to lengthen or counterclockwise to shorten stroke. Torque Iocknut after adjustment. h. Adjust rodend on actuator to approximately 1.88 inch dimension from center of bearing bolthole to face of jamnut i. Manually rotate jackshaft (12) to check that no interference exists. Recheck actuator (10) to lower arm of jackshaft (12) and secure with attaching hardware.

j. Disconnect control tube (2) and rotate idle (3) to assure that no interference exists. Reconnect tube (2) to idler (3) and secure with attaching hardware. k. Place and hold collective stick full down. I. Rotate cambox bellcrank to assure no interference exists. Connect tube (6), adjusted to hold cam, so that lower end of slot is 0.050 inch below slider housing (detail B) and secure with attaching hardware. m. With collective stick full down, hold RPM (beep) switch to DECR until actuator is fully extended.

CAUTION

Do not attempt to adjust minimum stop. n. Check at each governor (15 and 18) to assure some clearance exists between stop arm and stop screw. o. Place collective stick full up and hold RPM switch to INCR until actuator is fully retracted. Check governors for clearance between stop arm and stop screws.

CAUTION

If any maintenance has been performed in power lever controls and/or AFCU-MFCU area, comply with Maximum Gas Generator Speed (Ng) and Manual-Automatic Interconnect Linkage Adjustment, paragraph 4-247, before proceeding.

p. Have engines started and idled for 5 minutes. Pilot will actuate RPM switch to full INCR. q. With rotor at flat pitch, pilot will turn ENGINE 1 throttle grip to full INCR. Record rotor rpm. r. Have pilot actuate RPM switch to full DECR. Record rotor rpm. Pilot will then return throttle to idle.


4-206 Change 4

s. Perform same procedure for ENGINE 2. t. If rotor rpm range for ENGINE 1 is lower than for ENGINE 2, shorten tube (12, figure 4-39) until ranges coincide. If ENGINE 1 range is higher than ENGINE 2 range, lengthen tube until ranges coincide. Single engine desired beep range is 95 ± 0.5 to 99.5 ± 0.5 percent. It may be necessary to deviate from desired settings or percent to eliminate torque splits, maintaining minimum of 97 percent (Dual Range) at full INCR beep. 1. Adjust spread on ENGINE 2 by adjusting actuator (10) stroke. 2. Adjust spread on ENGINE 1 by moving control tube (13) in adjustable bellcrank (12); forward decreases and aft increases. 3. After obtaining desired spread, range can be increased or decreased by lengthening or shortening actuator (10) rodend. u. Pilot will now actuate RPM switch to full INCR and, with rotor at flat pitch, turn both ENGINE throttles to full INCREASE. Record rotor rpm. v. Have pilot actuate RPM switch to full DECR. Record rotor rpm. Adjust length of actuator rodend as required to obtain 97 + 0.5 to 101.5 ± 0.5 percent rpm range (shorten rod to raise range or lengthen rod to lower range).

NOTE

Tolerance of 0.5 percent applies only to upper limits.

w. With rotor at flat pitch, turn ENGINE 1 and 2 throttle grips to full INCREASE. Use RPM INCR-DECR switch to obtain 100 percent rotor rpm indication. Increase collective pitch slowly in a series of equal steps from flat pitch to full power (either engine temperature limit or transmission torque limit). Rotor rpm should remain at 100 (±1) percent through the power sweep. Also check that engine torque readings are matched within 4 percent. x. If rotor rpm droops (decays below tolerance) or overspeeds (increases above 100 percent) during power applications, a cam rate adjustment shall be made. For increased cam compensation to correct droop, adjust cam counterclockwise relative to bellcrank. (See detail B.) For reduced cam compensation to correct overspeed, adjust cam clockwise relative to bellcrank. After every cam adjustment, repeat

steps k. and I. to maintain required dimension of cam slot below slider housing. y. With collective stick full up and actuator retracted by RPM switch at INCR, adjust maximum power stop screw on governor to 0.010 inch of stop arm. (QA) z. Check system to assure no interference exists, and for security of all parts. (QA) 4-247. MAXIMUM Ng AND MANUAL TO AUTO-MATIC INTERCONNECT LINKAGE ADJUST-MENT. (See figure 4-78.).

CAUTION

Each power section's part power trim stop shall be properly stowed after completion of the maximum Ng check.

Maximum Ng check should be performed with aircraft on ground; if aircraft is not sufficiently weighted a low hover may result.

NOTE

Assure power lever controls are rigged in accordance with paragraph 4-245.

The maximum gas generator speed adjustment (Ng) and the manual to automatic interconnect linkage affect each other. Therefore the entire procedure in this check shall be carried out whenever adjustment is made to either of these.

To ensure the capability of setting the gas generator maximum speed (Ng) stop for power section under a wide variety of ambient conditions, without exceeding power section operating limits, a part power trim stop (7) is provided. This stop decreases maximum Ng speed obtainable by 3.5 percent to 4 percent thereby permitting maximum Ng to be adjusted at lower Ng speeds. The Part Power Trim Stop shall be used to set the maximum Ng speed unless due to extreme cold weather (typically tempera-tures below 25°F/ -4°C) the required Ng can not be obtained. During extreme cold weath-er, Slave Trim Stop, PWC 32821 may be used to further decrease the Ng speed so that the adjustment can be accomplished.


Change 2 4-207

a. Remove cotter pin (6) which secures part power trim stop (7) in stowed position. b. Rotate part power trim stop (7) so that it limits AFCU arm (8) travel. c. Install cotter pin (6) to secure part power trim stop (7) and bend back ends. (QA)

CAUTION

When the part power trim stop (7) is in the rigged or in use position, throttle (twist grip) movement is restricted. Attempting to force throttle to the full open position will bend interconnect linkage (3).

d. Assure that with the throttle (twist grip) full open, AFCU Ng stop screw (9) contacts part power trim stop (7) and MFCU max stop screw (10) does not contact MFCU stop (1). e. Start power section requiring adjustment and proceed as follows: 1. ENGINE GOV switch – AUTO. 2. Gradually increase collective and throttle control until maximum gas generator speed (Ng) is obtained. Run for 5 minutes at this power to achieve stable operating temperatures. Assure helicopter and engine operating limits are not exceeded.

CAUTION

Adjust collective pitch reset setting as necessary to assure maximum output shaft speed (Ns) is not exceeded.

f. Maximum Ng should fall within the range of 96.6 to 97.0 percent with normal trim stop or 91.6 to 92.0 percent with slave trim stop. If Ng does not fall within the appropriate range, proceed as follows: 1. Shut down engine to make adjustment. 2. Adjust AFCU Ng stop screw (9) to achieve an Ng of 96.6 to 97.0 percent with the normal trim stop or 91.6 to 92.0 percent with the slave trim stop. Turn counterclockwise to increase RPM and clockwise to decrease RPM.

CAUTION

The engine will display manual fuel characteristics with Pg line capped. Pilot

shall monitor instruments so that helicopter or engine limits are not exceeded. Assure Nf governor is reconnected at completion of test and that no Pg leak exists.

NOTE

Inability to attain proper Ng could indicate malfunctioning Nf Governor or Pg leaks. To check, first assure all fittings are tight. If this does not rectify problems, cap off Nf governor by installing a plug in Pg line and repeat steps e. and f.

Following adjustment of AFCU Ng stop screw, at least one stop screw thread must be visible on stop side (beneath) of the AFCU arm. Excessive counter-clockwise adjustment of AFCU Ng stop screw to raise Ng within proper range could indicate a discrepancy in automatic fuel control system.

3. Repeat step f.2. until maximum Ng is between 96.6 and 97.0 percent with normal trim stop and 91.6 to 92.0 percent with the slave trim stop.

CAUTION

Do not stow partial power trim stop (7) until max. Ng adjustment has been completed. Ng overspeed could result.

g. Shut down power section. h. Remove cotter pin (6) from part power trim stop (7) and rotate to stowed position. i. Install new cotter pin (6) to secure part power trim stop (7) in stowed position and bend back ends. Lockwire AFCU stop screw jamnut with MS9226-01 (QA). j. Rotate ENGINE throttle open until AFCU Ng stop screw (9) just contacts AFCU stop (14) and proceed as follows: 1. Check that the MFCU pointer indicates 90 degrees to 1/16 inch past 90 degrees. If not, adjust interconnect linkage nut (12) to obtain 90 degrees to 1/16 inch past 90 degrees. To adjust nut (12) depress interconnect spring (18) to release spacer (11) from nut (12).


4-208 Change 4

2. With MFCU pointer indicating 90 degrees to 1/16 inch past 90 degrees, check that the clearance between MFCU max stop screw (10) and MFCU stop (1) is 0.030 to 0.040 inch. Adjust MFCU max stop screw (10) as necessary to obtain this clearance. Lockwire with MS9226-01 after completing adjustment. 3. Rotate ENGINE throttle full closed until MFCU min stop screw (16) contacts MFCU stop (1). MFCU pointer should indicate 0 degrees +/- 1/16 inch. If MFCU pointer does not indicate 0 degrees +/- 1/16 inch, perform preliminary Automatic to Manual Fuel Control rigging (paragraph 4-243). k. Start power section requiring adjustment and proceed as follows: 1. Rotate ENGINE throttle (twist grip) to full INCREASE, then retard without using IDLE STOP RELEASE switch. Adjust stop on torque tube (23, figure 4-34) to obtain 61 +/- 2 percent Ng rpm when stop is in contact with plunger of solenoid (24). 2. Roll throttle to 61 percent Ng and lock throttles. Adjust rotor pitch to flat pitch, and minimum Nf/Nr RPM.

NOTE

Mild surges or pops during automatic to manual mode transfer are considered normal.

I. Position GOVERNOR switch from AUTO to MANUAL and back to AUTO. Verify that successful transfer has taken place in both directions by observing Ng gage for Ng deviation and stabilization within +/-6 percent. 1. If transfer does not occur, replace MFCU solenoid valve (paragraph 4-39).

CAUTION

During adjustment, check that torque required to turn self-locking interconnect linkage nut (12) is greater than 1.5 inch-pounds. If torque is 1.5 inch pounds or less, remove existing nut and replace with a new nut of the same type.

NOTE

If more than 10 threads are exposed past interconnect linkage nut (12, figure 4-78), interconnect linkage (3) may be bent. Interconnect linkage must be disassem-bled to check for a bent link.

2. If automatic to manual mode transfer is in excess of +/- 6 percent Ng, adjust the inter-connect linkage nut (12) clockwise to increase manual mode Ng or counterclockwise to de-crease manual mode Ng until Ng change on transfer is within limits. To adjust nut (12) depress interconnect spring (18) to release spacer (11) from nut (12). 3. If interconnecting linkage adjustment is performed, recheck AFCU to MFCU rigging (paragraph j.). If interconnect linkage adjustment cannot he accomplished to satisfy paragraph j. requirements and automatic to manual mode transfer requirements, replace MFCU.

Retaining Compound 4 4. Secure the nut (12) in its final adjusted position with retaining compound, MIL-S-22473 (ASTM D5363), Grade A. 5. Check that the spacer (11) correctly engages nut (12). (QA) m. Assure that MFCU max stop screw (10) is able to contact MFCU stop (1) by applying sufficient throttle (twist grip) pressure to compress interconnect linkage spring (18). MFCU pointer must indicate in excess of 90 degrees.

NOTE

Should it not be possible to reach 100 percent Ng due to ITT, fuel flow or helicopter limitations, assure that full AFCU arm travel is available with trim stop stowed and that engine meets performance requirements.

n. Following completion of max Ng and interconnect linkage adjustment, helicopter should be flown to sufficient altitude to become Ng limited. Maximum Ng must fall between 100 and 101 percent.


Change 3 4-209

NOTE

Certain engines will become ITT limited prior to becoming Ng limited regardless of the altitude because of internal speed and temperature match. Assure helicopter and engine operating limits are not exceeded.

1. If maximum Ng is below 100 percent, readjust AFCU Ng stop screw (9) counter-clockwise, per steps a. through i. preceding, up to a maximum of 97.5 percent Ng. One half of a turn changes Ng approximately 225 rpm or 0.5 percent. Recheck max Ng in flight. 2. If maximum Ng is above 101 percent, readjust AFCU Ng stop screw (9) clockwise per steps a. through i. preceding. One half of a turn changes Ng approximately 225 rpm or 0.5 percent. Recheck max Ng in flight. 3. If max Ng, max ITT, or max fuel flow cannot be attained, fly helicopter with engine in manual mode to an Ng of 100 to 101 percent. If an Ng of 100 to 101 percent can be obtained in manual mode, replace AFCU. If an Ng of 100 to 101 percent cannot be obtained in manual mode, remove fuel nozzles and clean or replace as necessary. Recheck max Ng in flight. 4. If adjustment is made to the AFCU Ng stop screw, recheck automatic to manual fuel control rigging and automatic to manual mode transfer per steps j. through m. preceding. 4-248. DELETED. 4-249. ACCELERATION CHECK AND ADJUST-MENT.

CAUTION

Do not under any circumstances attempt this check in MANUAL mode.

a. Start affected power section. b. ENG GOV Switches – AUTO. c. Collective – FULL DOWN. d. Set throttle – FLIGHT IDLE (61±2 percent Ng).

e. Throttle - FULL OPEN. Immediately after 90 percent Ng is reached, roll back throttle to FLIGHT IDLE stop. Note and record time required to accelerate from 61 to 90 percent Ng (should be 5 seconds maximum). If acceleration exceeds 5 seconds SHUT DOWN affected engine; then rotate acceleration adjuster (5, figure 4-78) clockwise to decrease time, counterclockwise to increase time, in increments of one click.

NOTE

If acceleration time is not met within a maximum of three clicks from datum line, the AFCU shall be replaced.

f. Restart engine and reperform check as per step e. above until achieving desired performance. 4-250. ITT TRIM CHECK AND ADJUSTMENT. (Figure 4-80.) a. Assure trim value marked on power section run sheet corresponds to trim value marked on power section data plate.

NOTE

Run sheet may contain trim values in Fahrenheit. Trim values represent changes in temperature. To obtain the equivalent change in Celsius, divide the Fahrenheit value by 1.8. Do not subtract 32.

b. Start affected power section and operate power section at stabilized level for 5 minutes to achieve a steady operating temperature. c. With affected engine operating stabilized at 700° C ITT or 93 percent Ng, pull respective ITT circuit breaker and observe and record ITT rise. d. The amount of ITT rise should correspond to the value determined in step a. (within + 5° C.) If not, close circuit breaker, remove cover (6, figure 4-80) of ITT limiter and adjust trim adjustment as follows:

CAUTION

Assure helicopter wiring harness termi-nals do not contact any portion of power section ITT lug shield or gas generator case after retaining nuts are torqued.


4-210 Change 2

Figure 4-80. ITT Limiter and Trim Adjustment

1. Disconnect thermocouple harness from ITT limiter and monitor output voltage of trim bias circuit at ITT limiter thermocouple input connector, pins A and B, using any standard 20,000 ohms/volt voltmeter. 2. Rotate trim bias adjustment repeatedly through its entire range until trim bias output voltage values obtained at extreme CW and CCW positions of adjustments are repeatable and steady (do not fluctuate when limiter is tapped). 3. Reconnect thermocouple harness and set trim bias adjustment to required trim value.

NOTE

By lowering the ITT trim bias, the temperature indicated in the aircraft will rise, or by increasing the ITT trim bias, the temperature indicated in the aircraft will drop.

e. Repeat step c. and note if indicated temperature rise is correct. If not, repeat step d. f. Replace cover (6, figure 4-80). Torque screws (5) 4 to 6 inch-pounds and Iockwire in pairs. (QA)

4-251. ITT THERMOCOUPLE HARNESS INSULA-TION RESISTANCE CHECK. To check harness when troubleshooting, proceed as follows:

CAUTION

When disconnecting, reconnecting and torquing ITT harness leads, support the terminal with a 5/16 inch open end wrench to prevent stress and/or cracking of ceramic in terminal block.

NOTE

Do not use digital multimeter to perform this check.

a. For Pre-PPC 76 power sections, dis-connect all electrical leads from ITT terminal block (see figure 4-81). For Post-PPC 76 power sections, remove chromel and alumel nuts (2, 3 figure 4-81) from studs in terminal stud support bracket (5). Then remove chromel and alumel jumper leads (8, 9) from studs in bracket (5).


Change 3 4-211

NOTE

Moisture in the T5 harness may cause low insulation resistance. If required, run the power section to dry out the harness, wait until the power section cools, then remeasure the insulation resistance.

b. For both Pre-PPC 76 and Post-PPC 76 power sections, using a Barfield tester or equivalent (1, figure 4-82), attach one terminal (2) to ground and the other terminal to the chromel post (3). Repeat test by attaching one terminal to ground and the other terminal to the alumel post (4). c. The minimum acceptable resistance is 10,000 ohms.

NOTE

Failure to meet requirements of step c. indicates that the thermocouple system is no longer serviceable and shall be replaced.

d. For Pre-PPC 76 power sections, re-connect all electrical leads to terminal block. Torque chromel nut (2, figure 4-81) to 8-12 inch pounds and alumel nut (3) to 10-15 inch pounds. For Post-PPC 76 power sections, reconnect chromel jumper lead (8, figure 4-81) to chromel stud in bracket (5) and torque chromel nut (2) to 8-12 inch pounds. Reconnect alumel jumper lead (9) to alumel stud in bracket (5) and torque alumel nut to 10-15 inch-pounds. (QA) 4-252. ITT THERMOCOUPLE HARNESS LOOP RESISTANCE CHECK. To check continuity and loop resistance measured across the chromel and alumel terminals, proceed as follows:

CAUTION

When disconnecting, reconnecting and torquing ITT harness leads, support the terminal with a 5/16 inch open end wrench to prevent stress and/or cracking of ceramic in terminal block.

NOTE

Do not use digital multimeter to perform this check.

a. For Pre-PPC 76 power sections, dis-connect all electrical leads from ITT terminal block (see figure 4-81). For Post-PPC 76 power sections, remove chromel and alumel nuts (2, 3 figure 4-81) from studs in terminal stud support bracket (5). Then remove chromel and alumel jumper leads (8, 9) from studs in bracket (5). b. For both Pre-PPC 76 and Post-PPC 76 power sections, using a Barfield tester or equivalent (1, figure 4-83), attach one terminal (2) to chromel post (3) and the other terminal (4) to the alumel post (5).

NOTE

Failure to meet requirements of step c. indicates that the thermocouple system is no longer serviceable and shall be replaced.

c. The maximum acceptable loop resistance is 1.0 to 2.8 ohms.

CAUTION


d. For Pre-PPC 76 power sections, re-connect all electrical leads to terminal block. Torque chromel nut (2, figure 4-81) to 8-12 inch-pounds and alumel nut (3) to 10-15 inch-pounds. For Post-PPC 76 power sections, reconnect chromel jumper lead (8, figure 4-81) to chromel stud in bracket (5) and torque chromel nut (2) to 8-12 inch pounds. Reconnect alumel jumper lead (9) to alumel stud in bracket (5) and torque alumel nut to 10-15 inch-pounds. (QA)


4-212 Change 2

Figure 4-81. ITT Terminal Block and Bracket Connections



4-252A. MAGNETIC CHIP DETECTOR, SCREW-IN TYPE - PRIOR TO ECP NO. T400-9. a. Disconnect cannon plug from chip detec-tor. b. Remove chip detector from detector valve body and reconnect cannon plug to chip detector. c. Apply a temporary short between the magnetic elements of the chip detector. Verify that the corresponding cockpit chip light illuminates. d. Remove the temporary short from chip detector. Disconnect cannon plug from chip detector. e. Install chip detector in detector valve body. Torque chip detector to 45 to 55 inch-pounds. Lockwire chip detector to valve body. f. Reconnect and Iockwire cannon plug to chip detector. 4-252B. MAGNETIC CHIP DETECTOR, BAYONET STYLE - AFTER ECP NO. T400-9.

NOTE

It is not necessary to disconnect the cannon plug from the chip detector in order to remove the chip detector from the detector valve body.

a. Remove chip detector from detector valve body. b. Apply a temporary short between the magnetic elements of the chip detector. Verify that the corresponding cockpit chip light illuminates.

NOTE

Bayonet style (ECP No. T400-9) chip detectors do not require Iockwire at the cannon plug-to-chip detector or the chip detector-to-detector valve body inter-faces.

c. Remove temporary short from chip detector. d. Install chip detector in detector valve body. Ensure the positive locking feature (chip detector-to-detector valve body) is completely engaged. 4-253. IGNITION SYSTEM CHECK.

WARNING

The voltage at spark igniters is dangerously high. Fuel switch must be OFF and ignition system inoperative for at least 6 minutes before removing any ignition component. Detach spark igniter coupling nut at spark igniter and touch connector contact to spark igniter body shield.

a. Assure throttle is in OFF position and fuel switch to ON. b. With desired starter switch engaged, listen at gas generator case for a snapping sound with a frequency of approximately one snap per second. c. Observe starter limits and switch starter to OFF position. d. If no sound is heard, check correctness of electrical supply circuit at ignition exciter and continuity of output leads to spark igniters. If no discontinuity is found, continue functional check of igniters.


Change 2 4-213

Figure 4-82. ITT Harness Insulation Resistance Check

Figure 4-83. ITT Harness Loop Resistance Check


4-214 Change 4

e. Disconnect spark igniter lead (at ignition exciter) of spark igniter not undergoing check. f. Engine fuel switch – ON and starter engaged. g. Listen at gas generator case for snapping sound with a frequency of approximately one snap per second. h. Position starter switch to OFF and turn engine fuel switch to OFF. i. If no sound was heard, replace spark igniter if steps a. to d., preceding, have verified integrity of ignition exciter and leads, or if replacement ignition exciter or lead has been installed. 4-254. SPARK IGNITER INSPECTION. Visually inspect and check the igniter plug thoroughly as follows: a. Inspect the terminal end for any visible evidence of damage.

NOTE

Minor nicks (0.02 maximum depth), burrs, or slightly damaged threads which can be erased by a few strokes of a fine file (AMS Swiss No. 2, or equivalent) may be repaired.

b. Reject igniter plug whenever any of the following conditions exist: 1. Insulator broken, cracked or loose. 2. Input connector pin noticeably damaged or bent. 3. Center electrode badly burned, broken or pitted. c. Inspect the electrode end of the igniter plug for wear and/or damage as follows: 1. Inspect firing tip insulator for radical cracks or pieces missing from ceramic insulator. Whenever insulator is defective, replace igniter plug.

2. Check outer electrode (shell) as follows: (a) Inspect electrode for erosion. Whenever inside dimension exceeds 0.250 inch, replace igniter plug. (b) Check electrode shell for burned area or melted area in tip of shell. Whenever burned area exceeds limits of 0.031 inch below surface at edge of shell, replace igniter plug. (c) Check OD of outer electrode for chafing wear. Whenever chafing wear equals or exceeds 0.015 inch, replace igniter plug. This measurement can be checked with a screw thread comparator No. 210 series micrometer caliper (CAGE 57163) or equivalent. (d) Check center electrode wear. Whenever electrode is recessed 0.031 inch below edge of shell, replace igniter plug. (e) Tip burn limits. Any burned or melted area in electrode shell is serviceable provided: (1) Ceramic OD is not exposed over total arc greater than 90 degrees. (2) Flange and metal shield of firing end is not bent, grooved, or eroded. Mating surface of flange must be flat and smooth. (3) Ceramic is intact with no cracks or looseness. 4-255. POWER ASSURANCE CHECK. Set alti-meter to 29.92 inches Hg to determine pressure altitude. a. At the bottom portion of figure 4-84, select the intended pressure altitude of functional flight test. Proceed horizontally to the right to intersect the curve, then vertically downwards to determine the percent torque value for power section undergoing check.

NOTE

Head helicopter into the wind before making check.


Change 4 4-215

b. Operate helicopter at pressure altitude and torque determined from figure 4-84.

NOTE

Assure that the heater is off and that the rotor is trimmed to 97 percent using the RPM INCR-DECR switch.

c. Operate at this condition and stabilize for 3 minutes, and note and record OAT, Nf, Ng and ITT, fuel flow, and engine torque of power section undergoing check. d. At the center third of figure 4-84, select the OAT and proceed upwards until pressure altitude line in center third of the graph is intersected. Proceed horizontally to the right to intersect gas generator speed percentage. Actual value of Ng obtained must be less than this value. e. At the center third of figure 4-84, select the OAT and proceed upwards until pressure altitude line of top of graph is intersected. Proceed horizontally to the left to intersect inter-turbine temperature value. Actual value of ITT obtained must be less than this value. 4-256. TOPPING CHECK.

CAUTION

Do not exceed Ng, Nf, ITT or torque limits during topping checks.

NOTE

Engine topping check is a means of determining whether or not the engine will reach one of three limits: Ng, ITT or fuel flow. In hot ambient conditions, ITT will normally he reached first; in cold weather at low altitude, the fuel flow limit may be reached; and Ng limit will be reached in cold weather at high altitude. The topping check is to determine if the engine will produce the torque indicated figure 4-85 at 100 percent Ng or 810°C ITT.

a. Set altimeter to 29.92 to read pressure altitude. b. Operate power section to be topped at 99.5 (±0.5) percent Nf. Slowly retard the other throttle to flight idle. Increase power on test power section until 810°C ITT or 100 percent Ng is reached. If neither of these limits are reached and fuel flow is approximately 580 pounds/hour, engine is fuel-flow limited. Climb to higher altitude where engine is not fuel-flow limited. If 810°C ITT is obtained before 100 percent Ng, the engine is ITT limited. If 100 percent Ng is obtained before 810°C ITT is obtained, the engine is Ng limited. c. If engine is ITT limited: Beep Nf to 97 percent and apply power slowly until 810°C ITT is reached. Stabilize at this power setting. Record OAT, Nf, Ng, ITT, fuel flow, engine torque and pressure altitude. d. If engine is Ng limited: With Nf at maximum, apply power until 100 percent Ng is obtained. If Nf droops prior to obtaining 100 percent Ng, have topping adjusted as required to obtain 100 percent Ng. If 100 percent Ng is reached with no Nf droop, apply power to maximum of 100.5 percent Ng to assure droop. If droop does not occur between 100.0 and 100.5 percent, a decrease in topping adjustment is required. Do not exceed ITT limits. With the engine topped and Nf drooped to 97 percent, record OAT, Nf, Ng, ITT, fuel flow, engine torque and pressure altitude. e. If the engine is topped to ITT and torque is low, the ITT bias shall be rechecked to confirm it is correct. Single-engine torque should indicate the same amount of torque when checking single-engine power required to hover (with the other power section at flight idle) on each power section. This is an excellent check of accuracy of both torque indicating gages and offers a good baseline for checking the other power parameter. This check may be done after initial hover checks or upon return if inflight power checks were not acceptable. f. After completion of topping, check that power available will equal or exceed values shown in figure 4-85.


4-216

Figure 4-84. Power Assurance Check Chart


4-217

Figure 4-85. Topping Check Chart


4-218 Change 5

4-257. AFCU MINIMUM GOVERNING SPEED ADJUSTMENT.

NOTE

Do no make this adjustment if helicopter is not operated below flight idle solenoid stop.

a. Start both power sections. b. Cap Pg port of AFCU to isolate Ng limiter.

NOTE

Cap on Pg port of AFCU will prevent sym-pathetic effects from Pg control system and will permit routine troubleshooting of power section controls.

c. Position ENG GOV switches to AUTO. d. Flight Idle Stop Switch – Actuate for power section undergoing check and slowly roll back throttle until pointer on MFCU (figure 4-78) indicates 30 to 35 degrees on its quadrant. e. Check that Ng is 52.0 to 55.0 percent. If not, adjust minimum governing speed adjust-ment (15, figure 4-78) to achieve requirement. f. Lockwire adjustment upon completion of check. (QA) g. Turn throttle past FLIGHT IDLE then back against flight idle stop. h. Remove cap from Pg port of AFCU. 4-258. TORQUE CONTROL UNIT MAXIMUM TORQUE LIMIT CHECK AND ADJUSTMENT (AFC 363 AIRCRAFT). Check will be accomplished on a functional test flight. a. Test Equipment Installation (Refer to figure 4-85A): 1. Disconnect and plug all four oil lines attached to the T-fittings on top of the Torque Control Unit (TCU) (7). 2. Tester to TCU Oil Hose Assembly (5): Connect straight fitting to the pressure tester (3)

and the 90 degree fitting to the TCU T-fitting as shown in figure. 3. TCU Transfer Oil Hose Assembly (6): Connect each fitting to TCU T-fittings as shown. 4. TCU to Transmitters Oil Hose Assembly (9): Connect single line with 90 degree fitting to TCU T-fitting as shown. Do not connect the other two lines of the assembly to the aircraft torque transmitter lines (10 and 11) at this time. b. Priming of Test Equipment (Refer to figure 4-85A): 1. Remove vented plug (2) from top of oil reservoir on pressure tester (3) and turn selector valve (1) arrow to point towards reservoir. 2. Rotate the pressure tester screw handle (4) fully clockwise (CW).

Lubricating Oil 1 3. Fill reservoir with engine oil, MIL-PRF-23699. 4. Rotate the screw handle (4) counterclockwise (CCW) and continue to fill reservoir with oil until screw handle is fully extended and oil level is within 1/8 inch from top of reservoir. Replace vented plug (2) on top of oil reservoir. 5. Turn selector valve (1) arrow to point towards tester outlet. 6. Rotate screw handle (4) CW until oil is noted flowing from TCU to Transmitters Oil Hose Assembly (9) at exit of both disconnected lines. Block exit of first line from which oil flows to allow oil to fill and exit other line. If screw handle reaches the full CW position prior to oil flow from TCU to Transmitters Oil Hose Assembly, refill pressure tester (3) per step c. 7. Once oil flow is noted from both TCU to Transmitters Oil Hose Assembly (9) lines, cap the exits of both lines.


Change 5 4-218A

c. Refill pressure tester (3, figure 4-85A) as follows if screw handle (4) reaches the full CW position during test: 1. Turn selector valve (1) arrow to point towards tester reservoir. 2. Remove vented plug (2) from top of oil reservoir. 3. Rotate the screw handle (4) CCW and continue to fill reservoir with oil until screw handle is fully extended and oil level is within 1/8 inch from top of reservoir. Replace vented plug (2) on top of oil reservoir. 4. Turn selector valve (1) arrow to point towards tester outlet and continue test. d. Leak Check of Test Equipment (Refer to figure 4-85A): 1. Disconnect both aircraft torque transmitter oil lines (10 and 11) from Reduction Gearbox (RGB). The other end of these oil lines is connected to the top of the torque transmitters. Cap oil fittings on RGB from which the torque transmitter oil lines were disconnected. 2. Connect TCU to Transmitters Oil Hose Assembly (9) to both aircraft torque transmitter lines (10 and 11) as shown.

NOTE

CW rotation of the pressure tester screw handle (4) increase pressure applied by pressure tester (3). CCW rotation of the pressure tester screw handle decreases pressure applied by pressure tester.

3. Rotate the screw handle (4) until a pressure of about 40 psig is indicated on pressure tester gage. If screw handle reaches the full CW position prior to an indication of 40 psig, refill tester per step c. 4. Inspect test line connection and gage on pressure tester (3) for indications of oil leaks. Note that pressure will settle at a lower pressure than originally set but will stabilize if no leaks are present. 5. Correct any leaks noted as required.

6. Rotate screw handle (4) to reduce pressure to about 15 psig as indicated on pressure tester gage. e. Torque Limiting Check and Adjustment (115% Torque) (Refer to figure 4-85A): 1. Start both power sections and stabilize at idle (61% Ng) for 5 minutes. Ensure both power sections are in automatic fuel mode. 2. Increase throttle to full open on both power sections. Set 100% Nr with RPM increase switch with rotor blades at flat pitch. Do not adjust Nr throughout the remainder of the test with the RPM increase switch.

CAUTION

To avoid damage to the torque control unit (7), never exceed 57 psig as indicated on the pressure gage.

NOTE

If screw handle (4) reaches the full CW position prior to Nr droop, refill tester per step c.

Throughout remainder of TCU adjustment procedure, do not increase or reduce Nr with input of the RPM increase switch. Leave beep setting at the original position as set in step e. 2.

3. Rotate pressure tester screw handle (4) to increase pressure until first indication of Nr droop. Note percent torque reading on cockpit torque gage at which Nr first droops. Required torque at Nr droop is 113 – 115% as measured from the pilot's torque indicator.

CAUTION

The torque limiter adjustment screw (8) is the only TCU (7) adjustment permitted.

NOTE

When adjusting TCU (7) with the allen wrench, 1/8 of a turn (one flat) changes the torque at which the TCU limits about 3-4%. CW adjustment of the TCU increases the torque limit and CCW adjustment decreases the torque limit.


4-218B Change 5

4. If Nr droop occurs below 113% torque, adjust TCU max limiting adjustment (8) CW using a 5/64 inch allen wrench to move adjustment above 115% torque. Observe that Nr is the same value as set in step e. 2. to ensure the TCU (7) is not limiting torque at this setting. Rotate pressure tester screw handle (4) until cockpit torque gage indicates 115%. Adjust pressure tester (3) as required throughout procedure to maintain 115% torque indication. Re-adjust TCU max limiting adjustment CCW until first indication of Nr droop. 5. If Nr droop occurs above 115% torque, rotate pressure tester screw handle (4) until cockpit torque gage indicates 115%. Adjust pressure tester (3) as required throughout procedure to maintain 115% torque indication. Using a 5/64 inch allen wrench, adjust TCU max limiting adjustment (8) CCW until first indication of Nr droop. 6. Re-check torque limiting adjustment, by rotating pressure tester screw handle (4) until cockpit torque gage indicates below 113%. Then repeat step e. 3. 7. Shut down both power sections. 8. Relieve pressure in oil lines by adjusting pressure tester (3) until pressure gage indicates 0 psig. Do not adjust pressure tester below 0 psig. Disconnect all oil hose assemblies from engine. 9. Reconnect and lockwire all disconnected TCU and torque transmitter lines. (QA) 4-258A. TORQUE CONTROL UNIT MAXIMUM TORQUE LIMIT CHECK AND ADJUSTMENT (PRE-AFC 363 AIRCRAFT). Check will be accomplished on a functional test flight.

NOTE

Overtorque on transmission up to 104 percent is permissible for 5 seconds or less during test.

a. Torque limiting should occur between 102 to 104 percent.

CAUTION

Screw (8, figure 4-17) is the only adjust-ment permitted.

NOTE

On hot day or high altitude conditions, it may not be possible to reach this torque limit.

b. When torque limiting occurs below 102 percent or does not occur by 104 percent transmission torque, perform following adjustments: 1. When torque limit is below 102 percent, using 5/64 allen wrench, turn torque limiter adjustment screw (8, figure 4-17) in 1/8 turn increments clockwise to raise limit. 2. When torque limit is not reached by 104 percent, using 5/64 allen wrench, turn torque limiter adjustment screw (8) in 1/8 turn increments counterclockwise to lower limit. Inability to adjust torque control may be caused by air in bellows. 4-258B. TORQUE CONTROL UNIT EQUALIZING FUNCTION CHECK. This check to be performed during troubleshooting for torque split. a. Shutdown engine.

Nitrogen 14 b. Connect pressure controlled air or nitrogen source to one of the torque control unit Pg ports. See figure 4-86. c. Establish supply of air or nitrogen at 16.8 psig ±0.2 psig. d. Differential pressure across airflow jet 2525107-67 shall be 1.0 to 3.0 inches of Hg. Reject TCU if differential pressure is out of limits. See figure 4-87. e. Repeat steps a. through d. on the other torque control unit Pg port.


Change 5 4-218C/(4-218D Blank)

Figure 4-85A. Torque Control Unit Maximum Limiting Check and Adjustment


4-219

Figure 4-86. Torque Control Unit Check

4-259. POWER TURBINE GOVERNOR MATCH-ING. For instructions on setting the power turbine governor maximum and minimum stops, refer to Rigging – Droop Compensator. Match the power turbine governors as follows: a. Shutdown both power sections. b. Disconnect both pneumatic sense lines at the torque control unit and seal off each line with fitting capable of withstanding pressure. Suitably blank the openings in the torque control unit. c. Start both power sections. d. ENG GOV switches – AUTO.

CAUTION

Assure that output shaft speed limita-tions are not exceeded.

e. Throttle – Slowly advance both power sections to full open.

CAUTION

This aircraft is susceptible to becoming airborne during following check. Assure precautions, such as increasing gross weight, are taken to prevent this. Assure output shaft speed and torque limitations are not exceeded.

NOTE

Accomplish this check only after operation checks have indicated a requirement for adjustment.

f. Gradually increase collective pitch until 47 percent transmission torque is attained. Observe that torque pressures of the two power sections are matched at 23.5 percent. Adjust control tube (12, figure 4-36) as necessary to match No. 1 power section with No. 2 power section.


4-220

NOTE If Ng speeds differ by more than 1.5 percent, a possible discrepancy with the torque pressure indicating systems may be suspected and should be checked for accuracy. g. Shut down both power sections. h. Remove blanking plugs from torque control unit and lifting from ends of torque control pneumatic sense lines. Install two control tubes on torque control unit fitting. 4-260. REDUCTION GEARBOX (RGB) OIL PRESSURE ADJUSTMENT. For RGBs incorpor-ating PPC 26, adjust the RGB oil pressure to within acceptable limits as follows: a. RGB oil pressure may be altered by changing quantity of spacers in the regulating valve assembly located inside the RGB behind the oil filler adapter (1, figure 4-88). Adding spacers increases oil pressure and removing spacers decreases oil pressure. Each spacer effects a 2 to 3 psi differential. b. To change the quantity of spacers in the RGB oil pressure regulating valve assembly, remove the oil filler adapter (1).

CAUTION

Caution should be exercised when removing the retaining ring. The valve housing is spring loaded and may be discharged from the pump housing when the retaining ring is removed.

c. Remove the retaining ring (5) which secures the valve housing (6) in the oil pressure pump housing. d. Remove the valve housing (6) from the pump housing. e. Add or remove spacers (7) located inside the valve housing (6) behind the spring (8) as necessary.

Figure 4-87. Air Flow Jet Installation


Change 2 4-221

Figure 4-88. Oil Pressure Regulating Valve Reduction Gearbox

f. Assemble and install the pressure regula-ting valve assembly (6 through 11, figure 4-88) into the pump housing and secure with the retaining ring (5). g. Install the oil filler adapter (1) onto the RGB. 4-261. WET MOTORING RUN. This procedure shall be accomplished as functional check of fuel system components.

CAUTION

Observe starter limits. Failure to disconnect ignition leads will result in inadvertent ignition.

a. Disconnect input lead from igniter exciter(s). b. With ENGINE 1 or 2 twist grip to full DECREASE and FUEL CONT switch ON, position GOV switch to AUTO. c. Position START switch ENG 1 or 2, and turn twist grip to IDLE after gas generator speed attains 12 percent rpm. d. Position GOV switch to MANUAL. e. Release START switch. Actuate IDLE STOP REL switch, return twist grip to full DECREASE, and return GOV switch to AUTO.


4-222 Change 5

f. Allow power section to run down and position FUEL CONT switch OFF. g. Reconnect input lead to ignition exciter(s).

CAUTION

Prior to starting engine, allow a 5 minute draining period and then conduct a dry motoring run.

4-262. DRY MOTORING RUN. Accomplish this pro-cedure whenever a dry motoring run of engine is required. a. With FUEL CONT switch OFF, position ENGINE 1 or 2 twist-grip to full DECREASE. b. Position START switch to ENG 1 or 2 for 20 seconds. c. Return START switch to OFF position and listen for unusual noises on coast-down. 4-263. COMPRESSOR WASH. Internal cleaning of engines equipped with compressor water wash spray rings will be accomplished by procedures below, as required for anticorrosion protection and for recovery of engine performance. 4-264. REQUIREMENTS. Desalination rinse pro-cedure will be performed under following conditions: a. Operation in salt water environment. b. Daily on all engines operated shipboard. c. On engines known to have ingested salt water during hover operations below 30 feet, as evidenced by salt deposits on helicopter. d. As a result of performance deterioration noted during or after flight or as scheduled by NAVAIR 01-110HCE-6-3. 4-265. MOTORING WASH FOR PERFORMANCE RECOVERY.

NOTE

To inject the required wash solution into the power section within the starter duty

cycle, assure that the spray ring is fitted with tee 3024090 or MS24402-6.

In reference to gas path cleaner specifi-cation MIL-PRF-85704, Type II and Type IIA are biodegradable wash detergents. Type IIA wash detergents are ready-for-use and require no mixing. Quality Products List number QPL-85704-6 provides a list of the approved detergents.

a. Prepare compressor wash solution for each power section by one of the following methods as applicable.

Gas Path Cleaner 15

Cleaning Compound 16 1. For ambient temperatures above 35°F (2°C), mix four quarts of water with one quart gas path cleaner conforming to MIL-PRF-85704, Type I or Type II, for a washing volume of 1-1/4 gallons for each wash. MIL-PRF-85704, Type IIA, designates ready-for-use aqueous cleaner and should not be diluted prior to use.

Methanol 17 2. For ambient temperatures of 35°F to -20° (2°C to -29°C), mix four quarts of a 40 percent methanol and 60 percent water solution with one quart of gas path cleaner conforming to MIL-PRF-85704, Type I or Type II, for a washing volume of 1-1/4 gallons for each wash. To use MIL-PRF-85704, Type IIA, gas path cleaner, mix 1-1/2 quarts of methanol with 3-1/2 quarts of Type IIA gas path cleaner for a washing volume of 1-1/4 gallons for each wash. b. Adjust water wash cart delivery pressure to flow at 1.3 gallons per minute (50 to 55 psi).


Change 3 4-223

CAUTION

Allow the engine to cool down for at least 40 minutes after shutdown before performing a motoring wash.

NOTE

Due to the ineffectiveness of the P3 air filter to separate B and B washing fluid, all engines with PPC No. 56 installed should have the subject filters removed prior to commencement of the power recovery wash. This will prevent B and B soap from being injected into the fuel controls. At completion of wash, the P3 air line between the filter housing and the gas generator case should be blown out.

c. If PPC 56 is incorporated, remove P3 filter. Remove cap (1, figure 4-21) from tee fitting (2) on P3 line that provides P3 pressure to the reduction gearbox for the clutch gear carbon seals. d. Fuel switch OFF and exciter deactivated before motoring commences. e. Open valve to the spray ring and permit cleaning solution to attain full flow. Immediately begin motoring the power section for maximum of 30 seconds. f. Close valve to spray ring and permit cleaning solution to soak for a minimum of 10 minutes to maximum of 30 minutes. g. Prepare compressor rinse solution for each power section by one of the following methods as applicable. 1. For ambient temperatures above 35° F, use 2-1/2 gallons of clean water for rinsing compressor. 2. For ambient temperatures of 35°F to -20°F (2°C to -29°C), use a 40 percent methyl alcohol, O-M-232, and 60 percent water solution for a volume of 2-1/2 gallons for rinsing compressor.

NOTE

When rinse is accomplished using alco-hol solution, perform a dry motoring

run after wash to purge fumes from engine.

h. Adjust water wash cart delivery pressure to flow at 1.3 gallons per minute. (5 to 55 psi) i. Fuel switch OFF and exciter deactivated before motoring commences. j. Open valve to the spray ring and permit rinse solution to attain full flow. Immediately begin monitoring the power section for a maxi-mum of 30 seconds. k. Continue flow of rinse solution for 5 more seconds after motoring cycle then close valve to the spray ring. l. Repeat instructions in steps h. through k. one more time. m. Allow starter to cool for 10 minutes. Motor power section for 30 seconds maximum ensuring that fluids are not injected. Repeat one time. n. After completion of rinse cycle, if PPC 56 is incorporated, blow residual moisture out of P3 filter housing using compressed air. Replace packings on P3 filter and P3 filter cover. Reinstall P3 filter in accordance with paragraph 4-75. Reinstall cap (1, figure 4-21) on tee fitting (2) on P3 line. Torque cap 90 to 100 inch-pounds and secure with lockwire, MS9226-03. (QA) o. Start engine and run at idle for 3 minutes minimum to completely dry power section. Operate bleed air heater for at least 1 minute during idle run to remove trapped fluid to prevent sticking valves and to ensure proper operation. 4-266. MOTORING RINSE FOR DESALINATION.

NOTE

To inject the required rinse solution into the power section within the starter duty cycle, assure that the spray ring is fitted with tee 3024090 or MS24402-6.

a. Prepare compressor rinse solution for each power section by one of the following methods as applicable.


4-224 Change 5

1. For ambient temperatures above 35°F (2°C), use 3-1/2 gallons of clean water for rinsing compressor.

Methanol 17 2. For ambient temperatures of 35°F to -20°F (2°C to -29°C), use 40 percent methanol, O-M-232, and 60 percent water solution for a, volume of 3-1/2 gallons to rinse compressor.

NOTE

When rinse is accomplished using alcohol solution, perform a dry motoring run after wash to purge fumes from engine.

b. Adjust water wash cart delivery pressure to flow at 1.3 gallons per minute. (50 to 55 psi)

CAUTION

Allow the engine to cool down for at least 40 minutes after shutdown before performing a motoring rinse.

NOTE

Due to the ineffectiveness of the P3 air filter in separating rinse fluid, all engines with PPC 56 installed should have the subject filters removed prior to beginning the desalination wash. This will prevent rinse fluid from being injected into the fuel controls. At completion of wash, the P3 air line between the filter housing and the gas generator case should be blown out.

c. If PPC 56 is incorporated, remove P3 filter. Remove cap (1, figure 4-21) from tee fitting (2) on P3 line that provides P3 pressure to the reduction gearbox for the clutch gear carbon seals. d. Fuel switch OFF and exciter deactivated before motoring commences. e. Open valve to the spray ring and permit rinse solution to attain full flow. Immediately begin motoring the power section for maximum of 30 seconds. f. Continue flow of rinse solution for 5 to 10 seconds after motoring cycle then shut off valve to spray ring.

g. Allow starter to cool for 1 minute and then repeat steps b. through e. one more time. h. Allow starter to cool for 10 minutes. Motor power section for 30 seconds maximum ensuring that fluids are not injected. Repeat one time. i. After completion of rinse cycle, if PPC 56 is incorporated, blow residual moisture out of P3 filter housing using compressed air. Replace packings on P3 filter and P3 filter cover. Reinstall P3 filter in accordance with paragraph 4-75. Reinstall cap (1, figure 4-21) on tee fitting (2) on P3 line. Torque cap 90 to 100 inch-pounds and secure with lockwire, MS9226-03. (QA) j. Start engine and run at idle for 3 minutes to completely dry power section. Operate bleed air heater for at least 1 minute during idle run to remove trapped fluid to prevent sticking valves and to ensure proper operation. 4-267. POWER SECTION OIL PRESSURE CHECK/ ADJUSTMENT. This procedure is normally accomplished after change of power section or change of power section oil system components of airframe oil cooler, lines, etc. or when so directed by troubleshooting. a. Start affected power section and operate at a torquemeter pressure of 40±2 percent for 10 minutes to allow stabilization of oil temperature. b. Power section oil pressure at stabilized temperature should be within the range specified in figure 4-89. Note and record oil temperature and oil pressure.

NOTE

Power section oil pressure fluctuation of ±5 psi is allowable.

c. Shut down power section. d. Oil pressure is altered by changing quantity of spacers in check and relief valve. Adding spacers increases oil pressure and removing spacers decreases pressure. Each spacer corresponds to a pressure alteration of 3 to 4 psig.


Change 5 4-225

Figure 4-89. Oil Temperature vs. Oil Pressure

e. If required, change quantity of spacers as follows (see figure 4-90):

Lubricating Oil 1 1. Place suitable container under valve housing (7) to catch any residual oil.

2. Remove four bolts (1) and washers (2) and retain cover (12) in position by hand pressure. 3. Carefully remove cover (12), spring (10), spacers (9) and regulating valve (8). 4. Install required number of spacers (9) into regulating valve (8) and install valve into housing (7). Maximum permissible quantity of spacers is ten. 5. Install spring (10).


4-226 Change 5

Figure 4-90. Power Section Oil Pressure Regulating Valve Adjustment


Change 5 4-227

Lubricating Oil 1 6. Lubricate preformed packing (11, figure 4-90) with lubricating oil, MIL-PRF-23699, and install on face of housing cover (12). Secure cover to housing (7) with four bolts (1) and washers (2). Torque bolts 32 to 36 inch-pounds and Iockwire in pairs. (QA) f. Repeat steps a., b. and c. 4-268. COMPRESSOR BLEED VALVE. A com-pressor bleed valve is located at 5 o'clock position (looking forward from the reduction gearbox) of each gas generator case. To provide anti-stall characteristics, the valve opens to spill interstage compressor air (P2.5) at low compressor speeds. The valve remains closed at higher speeds. 4-269. TEST PROCEDURE – PPC 86. a. Remove bleed valve from power section per paragraph 4-271. b. If the bleed valve is being replaced, pre-adjust replacement bleed valve as follows (refer to figure 4-91): 1. Loosen the double hex self-locking screw to release the hex adjustment screw. 2. Turn the hex adjustment screw fully clockwise until rotation of adjustment screw stops. Then rotate adjustment screw 10 flats counterclockwise. This should set bleed valve closer to the final setting to reduce the number of adjustments. 3. While holding the hex adjustment screw with a wrench, tighten the double hex self-locking screw 17 – 20 in.-lbs. to lock the hex adjustment screw. (QA) c. Adjust the adjustable bubbler assembly, P/N PWC70513, as follows (refer to figure 4-91): 1. Loosen the two hexagonal cap screws on the adjustable bubbler assembly to let the bubbler tube move freely on the bubbler bracket. 2. Remove lockwire from the bleed valve blanking plug to allow for installation of bubbler assembly. 3. Place the bubbler assembly on the bleed valve as shown, aligning the boltholes of

the bubbler bracket with the bleed valve boltholes.

NOTE

Ensure the adjustable bubbler assembly bracket contact faces are held flat against the bleed valve assembly during the following five steps.

4. Insert a piece of 0.001 inch thick shim stock between the bottom of the bubbler tube and the bleed valve housing flange. 5. Adjust the bubbler tube against the shim stock. The flared end of the bubbler tube should be located just radially outward from the edge of the piston contact surface on the bleed valve seat. This is to ensure the bubbler tube does not interfere with the operation of the bleed valve piston. 6. While holding the bubbler tube in position against the shim stock and the bubbler bracket flat against the bleed valve housing flange, finger tighten the two hexagonal cap screws to fix the bubbler tube adjustment. 7. Tighten the two hexagonal cap screws to 16 – 20 in.-lbs. 8. Remove the shim and ensure the gap of 0.001 inch remains between the bottom of the bubbler tube and the bleed valve housing flange. 9. Remove the bubbler assembly from the bleed valve and lockwire the two hexagonal cap screws. d. Install bleed valve and adjustable bubbler assembly for closing point check as follows (refer to figure 4-92):

Petrolatum 5 1. Lubricate preformed packing (1) with petrolatum, VV-P-236, and install in groove at the base of the bleed valve assembly spring pin (2). 2. Position the adjustable bubbler assembly on the bleed valve.

CAUTION

Ensure the adjustable bubbler assembly tube is not positioned to interfere with travel of the bleed valve assembly piston.


4-228 Change 5

3. Install the bleed valve with the bubbler assembly on the gas generator case aligning the boltholes and the spring pin with its mating hole. Secure with four bolts (3) and two washers (4). The two bolts that secure the bubbler assembly do not require washers. Tighten the four bolts to 16 – 20 in.-lbs. (QA)

NOTE

Tubing (included with the adjustable bubbler assembly) may be shortened by removing an end fitting, cutting tubing to desired length, and replacing the end fitting. Shorter tubing lengths will provide a quicker response time for initiation of bubbling in bottle. A length of 3-1/2 to 4 feet is recommended for bleed valve adjustment on aircraft.

4. Attach the elbow to the bubbler assembly and one end of the flexible tubing to the elbow (all included with the bubbler assembly, P/N PWC70513). Torque finger tight only. 5. Disconnect tubing from bottle (included with the adjustable bubbler assembly) and route to avoid contact with a hot surface. Tubing may be routed through gap below front fireseal at the six o’clock position or through corner of induction baffle assembly door. If tubing is routed through induction baffle assembly door, attach door to induction baffle as secure as possible to reduce air leaks around door but not to crush tubing. 6. Fill the bottle with water to level that will provide a maximum depth of 1.5 inches above the end of the tube. Mount bottle in any appropriate location. Leave tubing disconnected from bottle at this time to prevent loss of water during engine start. e. Perform bleed valve closing point check as follows:

NOTE

Close the associated induction baffle door prior to check. Failure to close induction baffle door will cause an inaccurate closing point determination.

1. Start power section and stabilize at 61% Ng.

2. Attach tubing to bottle and torque finger tight only. Observe that water in bottle is bubbling indicating the bleed valve is open. Bubbling may not be observed until 75 – 77% Ng is reached. 3. Increase throttle until bubbling of water in bottle ceases indicating the bleed valve is closed. 4. Record percent Ng when the bubbling ceases. Also record the Outside Air Temperature (OAT) and altitude during check. 5. Shut down power section. 6. Determine the required Ng at bleed valve closing by plotting the recorded OAT against the recorded altitude on figure 4-93, and then reading across to obtain %Ng. 7. Check that the actual Ng at bleed valve closing is within 0.0% to +2.1% of the required Ng at bleed valve closing. 8. If Ng at bleed valve closing is within limits, perform final bleed valve installation per paragraph 4-269.g. If Ng at bleed valve closing is not within limits, adjust bleed valve per paragraph 4-269.f. f. Adjust bleed valve closing point as follows (refer to figure 4-91): 1. Remove bleed valve assembly from gas generator case as required to access bleed valve adjustment. 2. Loosen the double hex self-locking screw to release the hex adjustment screw. 3. Turn the hex adjustment screw clockwise to increase or counterclockwise to decrease Ng at the closing point. A 60 degree rotation (i.e. one flat of the hex adjustment screw) changes Ng approximately 2%. 4. While holding the hex adjustment screw with a wrench, tighten the double hex self-locking screw 17 – 20 in.-lbs. to lock the hex adjustment screw. (QA) 5. If removed, re-install bleed valve assembly per paragraph 4-269.d.


Change 5 4-229

6. Repeat bleed valve check and adjustment per paragraphs 4-269.e. and 4-269.f. until the Ng closing point is within limits. g. Perform final bleed valve installation following closing point adjustment as follows: 1. Remove two bolts (3, figure 4-92) securing the adjustable bubbler assembly. 2. Remove bubbler assembly from the bleed valve. 3. Re-install the two bolts with two washers (4). Tighten the bolts to 16 – 20 in. lbs. (QA) 4. Lockwire the four bolts using MS9226-03. Single strand lockwire through all four bolts authorized. (QA) 5. Lockwire blanking plug (refer to figure 4-91) to bleed valve using MS9226-03. (QA) h. Bleed valves that cannot be adjusted within the required closing point must be returned to Intermediate Maintenance and replaced by another bleed valve. 4-270. TEST PROCEDURE – PRE-PPC 86. a. Manufacture a test bracket per figure 4-94.

NOTE

Tubing should be able to withstand 100 psi pressure or better.

b. Slip a piece of 3/16 inch ID plastic tubing over the unflared end of the aluminum tubing. Length of plastic tubing should be as short as possible to prevent delay in response time but long enough to allow safe observation of bubbler bottle. c. Mount bracket by removing the inside 2 bleed valve retaining bolts, 3012260; insert bracket flared end down and then reinstall bolts. d. Place a length of 3/16 inch OD tubing into a clear bottle. Secure the tube by any appropriate means. Do not seal bottle. e. Fill the bottle with water until the tube is immersed by approximately 1/2 inch. Use of a coloring agent in the water will aid test.

f. Slip the free end of the plastic tubing over the bottle tubing. g. Start power section in accordance with appropriate manual. Observe that water in bottle is bubbling. h. Increase throttle and note percent Ng rpm when bubbling stops.

NOTE

Valve closing significantly below minimum point can cause compressor stalls. Closing point above max can cause low power. Replace bleed valve if defective.

i. Bleed valve should close per figure 4-95. 4-271. REMOVAL. (Figure 4-92.) a. Remove four bolts (3 or 5) and washers (4 or 6) securing compressor bleed valve (7 or 8) to gas generator case. b. Withdraw compressor bleed valve from gas generator case. 4-272. INSTALLATION. (Figure 4-92.)

Petrolatum 5 a. Install new packing (1), lubricated with petrolatum, VV-P-236, on spring pin (2).

CAUTION

Do not overtorque bolts as damage to diaphragm may result.

b. Install bleed valve (7 or 8) on gas generator case. Secure with four washers (4 or 6) and bolts (3 or 5). Torque bolts to 16 to 20 inch-pounds and secure with single strand lockwire through all four bolts. (QA)


4-230 Change 5

Figure 4-91. PPC 86 Bleed Valve and Bubbler Assembly, P/N PWC70513, Adjustment


Change 5 4-231

Figure 4-92. Compressor Bleed Valve – Installation/Removal


4-232 Change 5

Figure 4-93. PPC 86 Compressor Bleed Air Valve Closing Point Chart


Change 5 4-233

Figure 4-94. Pre-PPC 86 Fabrication of Bleed Air Valve Bracket


4-234 Change 5

Figure 4-95. Pre-PPC 86 Compressor Bleed Air Valve Closing Point Chart


Change 4 Index-1

ALPHABETICAL INDEX Subject Paragraph Number

A Acceleration Check and Adjustment .......................................................................................................... 4-249 Accessory Drive Seal ................................................................................................................................... 4-17 Replacement of Blower Drive – Drive Seal ................................................................................... 4-23 Replacement of Fuel Pump Drive Seal .......................................................................................... 4-18 Replacement of Nf Tachometer-Generator Drive Seal ................................................................. 4-22 Replacement of Ng Tachometer-Generator Drive Seal ................................................................ 4-20 Replacement of Power Turbine Governor Drive Seal .................................................................. 4-21 Replacement of Starter-Generator Drive Seal .............................................................................. 4-19 Accessory Gearbox Pressure Oil Tube ...................................................................................................... 4-98 Installation ........................................................................................................................................ 4-100 Removal ............................................................................................................................................ 4-99 AFCU Minimum Governing Speed Adjustment .......................................................................................... 4-257 Aft Fuel Cells ................................................................................................................................................. 4-226 Installation ........................................................................................................................................ 4-228 Removal ............................................................................................................................................ 4-227 Air Management System .............................................................................................................................. 2-11, 4-156 Description ....................................................................................................................................... 2-12 Installation ........................................................................................................................................ 4-159 Maintenance...................................................................................................................................... 4-157 Operation .......................................................................................................................................... 2-13 Removal ............................................................................................................................................ 4-158 Automatic Fuel Control Units ...................................................................................................................... 4-30 Installation ........................................................................................................................................ 4-32 Removal ............................................................................................................................................ 4-31 Auxiliary Fuel System .................................................................................................................................. 2-27 4-239 Description ....................................................................................................................................... 2-28 Function ............................................................................................................................................ 2-29 Installation ........................................................................................................................................ 4-242 Operational Checkout ..................................................................................................................... 4-240 Troubleshooting .............................................................................................................................. 4-241

B Bearing Scavenge Oil Tube (No. 2) ............................................................................................................. 4-83 Installation ........................................................................................................................................ 4-85 Removal ............................................................................................................................................ 4-84 Blowers – Oil Cooler .................................................................................................................................... 4-172 Inspection ........................................................................................................................................ 4-174 Installation ........................................................................................................................................ 4-175 Removal ............................................................................................................................................ 4-173


Index-2 Change 5

ALPHABETICAL INDEX – (Continued) Subject Paragraph Number

C Cambox Assembly ........................................................................................................................................ 4-147 Installation ........................................................................................................................................ 4-150 Removal ............................................................................................................................................ 4-148 Centrifugal Breather Face - Type Carbon Seal ......................................................................................... 4-10 Installation ........................................................................................................................................ 4-12 Removal ............................................................................................................................................ 4-11 Combustion Chamber Drain Valves ........................................................................................................... 4-60 Cleaning ............................................................................................................................................ 4-62 Installation ........................................................................................................................................ 4-63 Removal ............................................................................................................................................ 4-61 Compressor Bleed Valve ............................................................................................................................ 4-268 Installation ........................................................................................................................................ 4-272 Removal ............................................................................................................................................ 4-271 Test Procedures – PPC 86 ............................................................................................................... 4-269 Test Procedures – Pre-PPC 86........................................................................................................ 4-270 Compressor Inlet Screen – Prior to PPC No. 9A ....................................................................................... 4-48 Installation ........................................................................................................................................ 4-50 Removal ............................................................................................................................................ 4-49 Compressor Inlet Screen and Compressor Spray Ring – Incorporating PPC No. 9A ............................................................................................................... 4-51 Installation ........................................................................................................................................ 4-53 Removal ............................................................................................................................................ 4-52 Compressor Wash ........................................................................................................................................ 4-263 Motoring Rinse for Desalination .................................................................................................... 4-266 Motoring Wash for Performance Recovery .................................................................................. 4-265 Requirements ................................................................................................................................... 4-264 Consumable Materials .................................................................................................................................. 1-9 Controls – Droop Compensator (Nf) ........................................................................................................... 2-8, 4-145 Description ....................................................................................................................................... 2-9 Inspection ......................................................................................................................................... 4-149 Installation ........................................................................................................................................ 4-151 Operation .......................................................................................................................................... 2-10 Removal ............................................................................................................................................ 4-146 Controls – Power Lever (Ng) ........................................................................................................................ 2-5, 4-135 Description ....................................................................................................................................... 2-6 Inspection ......................................................................................................................................... 4-137 Installation ........................................................................................................................................ 4-138 Operation .......................................................................................................................................... 2-7 Removal ............................................................................................................................................ 4-138 Cowling........................................................................................................................................................... 4-152 Adjustment ........................................................................................................................................ 4-155 Installation......................................................................................................................................... 4-154 Removal............................................................................................................................................. 4-153


Change 4 Index-3

ALPHABETICAL INDEX – (Continued) Subject Paragraph Number

D Droop Compensator (Nf) Controls .............................................................................................................. 2-8, 4-145 Description ....................................................................................................................................... 2-9 Inspection ......................................................................................................................................... 4-149 Installation ........................................................................................................................................ 4-151 Operation .......................................................................................................................................... 2-10 Removal ............................................................................................................................................ 4-146

E Engine Compartment Fire Extinguisher Installation ................................................................................. 2-18, 4-180 Description ....................................................................................................................................... 2-19 Inspection and Repair ..................................................................................................................... 4-182 Maintenance ..................................................................................................................................... 4-181 Operation .......................................................................................................................................... 2-20 Engine Mounts .............................................................................................................................................. 2-16, 4-176 Description ....................................................................................................................................... 2-17 Installation ........................................................................................................................................ 4-179 Maintenance ..................................................................................................................................... 4-177 Removal ............................................................................................................................................ 4-178 Engine Water Wash Provisions ................................................................................................................... 4-197 Description ....................................................................................................................................... 4-198 Inspection ......................................................................................................................................... 4-200 Installation ........................................................................................................................................ 4-202 Repair or Replacement ................................................................................................................... 4-201 Removal ............................................................................................................................................ 4-199 Exciters – Ignition ......................................................................................................................................... 4-42 Installation ........................................................................................................................................ 4-44 Removal ............................................................................................................................................ 4-43

F Filters – Fuel .................................................................................................................................................. 4-209 Replacement .................................................................................................................................... 4-210 Filter – Fuel Pump ......................................................................................................................................... 4-27 Installation ........................................................................................................................................ 4-29 Removal ............................................................................................................................................ 4-28 Filter – Reduction Gearbox OiI .................................................................................................................... 4-7 Installation ........................................................................................................................................ 4-9 Removal ............................................................................................................................................ 4-8


Index-4 Change 4

ALPHABETICAL INDEX (Continued) Subject Paragraph Number

F (Continued) Firewalls ........................................................................................................................................................ 4-160 Installation ........................................................................................................................................ 4-164 Inspection ......................................................................................................................................... 4-162 Removal ............................................................................................................................................ 4-161 Repair ................................................................................................................................................ 4-163 Flow Dividers ................................................................................................................................................ 4-54 Installation ........................................................................................................................................ 4-56 Removal ............................................................................................................................................ 4-55 Forward Fuel Cells ........................................................................................................................................ 4-229 Installation – Forward Fuel Cells ................................................................................................... 4-238 Installation – Forward Fuel Cell Sump Assembly ........................................................................ 4-236 Removal – Forward Fuel Cells ....................................................................................................... 4-237 Removal – Forward Fuel Cell Sump Assembly ............................................................................ 4-230 Replacing Cartridge (2C27-3) ......................................................................................................... 4-232 Replacing Float Switch ................................................................................................................... 4-234 Replacing Flow Switch .................................................................................................................... 4-233 Replacing Fuel Boost Pump ........................................................................................................... 4-231 Replacing Sump Drain Valve .......................................................................................................... 4-235 Fuel Cells – Aft .............................................................................................................................................. 4-226 Installation ........................................................................................................................................ 4-228 Removal ............................................................................................................................................ 4-227 Fuel Cells – Forward .................................................................................................................................... 4-229 Installation – Forward Fuel Cells ................................................................................................... 4-238 Installation – Forward Fuel Cell Sump Assembly ........................................................................ 4-236 Removal – Forward Fuel Cells ....................................................................................................... 4-237 Removal – Forward Fuel Cell Sump Assembly ............................................................................ 4-230 Replacing Cartridge (2C27-3) ......................................................................................................... 4-232 Replacing Float Switch ................................................................................................................... 4-234 Replacing Flow Switch .................................................................................................................... 4-233 Replacing Fuel Boost Pump ........................................................................................................... 4-231 Replacing Sump Drain Valve .......................................................................................................... 4-235 Fuel Control Unit Solenoid Valve ................................................................................................................ 4-39 Installation ........................................................................................................................................ 4-41 Removal ............................................................................................................................................ 4-40 Fuel Filters ..................................................................................................................................................... 4-209 Replacing Filter Element ................................................................................................................. 4-210 Fuel Manifold Adapter Assembly ................................................................................................................ 4-57 Installation ........................................................................................................................................ 4-59 Removal ............................................................................................................................................ 4-58 Fuel Pump Filters .......................................................................................................................................... 4-27 Installation ........................................................................................................................................ 4-29 Removal ............................................................................................................................................ 4-28


Change 4 Index-5

ALPHABETICAL INDEX - (Continued) Subject Paragraph Number

F (Continued) Fuel Pumps ................................................................................................................................................... 4-36 Installation ........................................................................................................................................ 4-38 Removal ............................................................................................................................................ 4-37 Fuel Shutoff Valves ...................................................................................................................................... 4-211 Installation – Shutoff Valve ............................................................................................................. 4-213 Removal – Shutoff Valve ................................................................................................................. 4-212 Fuel Supply System ...................................................................................................................................... 2-21 4-203 Description ....................................................................................................................................... 2-22 Operation .......................................................................................................................................... 4-204 Operation Checkout ........................................................................................................................ 4-207 Troubleshooting .............................................................................................................................. 4-208 Fuel Surge Accumulator ............................................................................................................................... 4-121 Inspection and Cleaning .................................................................................................................. 4-123 Installation......................................................................................................................................... 4-121 Removal............................................................................................................................................. 4-122 Fuel Surge Dampener .................................................................................................................................. 4-115 Assembly .......................................................................................................................................... 4-119 Disassembly ..................................................................................................................................... 4-117 Inspection and Cleaning ................................................................................................................. 4-118 Installation ........................................................................................................................................ 4-120 Removal ............................................................................................................................................ 4-116 Fuel System – Auxiliary ............................................................................................................................... 2-27 4-239 Description ....................................................................................................................................... 2-28 Function ............................................................................................................................................ 2-29 Installation ........................................................................................................................................ 4-242 Operational Checkout ..................................................................................................................... 4-240 Troubleshooting .............................................................................................................................. 4-241 Fuel Transfer Tubes ..................................................................................................................................... 4-112 Installation ........................................................................................................................................ 4-114 Removal ............................................................................................................................................ 4-113

G General ........................................................................................................................................................... 1-1 Glossary of Terms, Symbols and Abbreviations ...................................................................................... 1-15

H Heaters – Oil-To-Fuel ................................................................................................................................... 4-24 Installation ........................................................................................................................................ 4-26 Removal ............................................................................................................................................ 4-25

I Idle Stop Assembly ....................................................................................................................................... 4-142 Installation ........................................................................................................................................ 4-144 Removal ............................................................................................................................................ 4-143


Index-6 Change 4


I (Continued) Idle Stop Solenoids ...................................................................................................................................... 4-139 Installation ........................................................................................................................................ 4-141 Removal ............................................................................................................................................ 4-140 Ignition Exciters ............................................................................................................................................ 4-42 Installation ........................................................................................................................................ 4-44 Removal ............................................................................................................................................ 4-43 Ignition System Check ................................................................................................................................. 4-253 Insulated and Heated Tubes ........................................................................................................................ 4-107 Minor Repair - Insulated and Heated Tubes ................................................................................. 4-109 ITT Trim Bias Unit ......................................................................................................................................... 4-126 Installation ........................................................................................................................................ 4-128 Removal ............................................................................................................................................ 4-127 ITT Limiter System ........................................................................................................................................ 4-125 ITT Thermocouple Harness Insulation Resistance Check ....................................................................... 4-251 ITT Thermocouple Harness Loop Resistance Check ............................................................................... 4-252 ITT Trim Check and Adjustment ................................................................................................................. 4-250

L Lubrication and Servicing ........................................................................................................................... 1-5

M Magnetic Chip Detector, Bayonet Style – After ECP No. T400-9 .............................................................. 4-252B Magnetic Chip Detector, Screw-In Type – Prior to ECP No. T400-9 ......................................................... 4-252A Manual Fuel Control Units ........................................................................................................................... 4-33 Installation ........................................................................................................................................ 4-35 Removal ............................................................................................................................................ 4-34 Maximum Ng and Manual To Automatic Interconnect Linkage Adjustment ........................................... 4-247 Motoring Rinse For Desalination ................................................................................................................. 4-266 Motoring Wash for Performance Recovery ................................................................................................ 4-265

N No. 2 Bearing Scavenge Oil Tube ............................................................................................................... 4-83 Installation ........................................................................................................................................ 4-85 Removal ............................................................................................................................................ 4-84

O Oil Cooler Blowers ........................................................................................................................................ 4-172 Inspection ......................................................................................................................................... 4-174 Installation ........................................................................................................................................ 4-175 Removal ............................................................................................................................................ 4-173


Change 4 Index-7


O (Continued) Oil Cooler System ......................................................................................................................................... 2-14, 4-165 Cleaning Exterior of Oil Coolers .................................................................................................... 4-168 Description ....................................................................................................................................... 2-15 Installation – Engine Oil Coolers ................................................................................................... 4-169 Installation – Reduction Gearbox Oil Cooler ................................................................................ 4-171 Maintenance – Oil Cooler System .................................................................................................. 4-166 Removal – Engine Oil Coolers ....................................................................................................... 4-167 Removal – Reduction Gearbox Oil Cooler .................................................................................... 4-170 Oil-To-Fuel Heaters ....................................................................................................................................... 4-24 Installation ........................................................................................................................................ 4-26 Removal ............................................................................................................................................ 4-25 Output Shaft Face-Type Seal and Runner – Prior to PPC No. 8 and RGB No. 3168 ........................................................................................................................... 4-13 Replacement .................................................................................................................................... 4-14 Output Shaft Face-Type Seal and Runner – Incorporating PPC No. 8 and RGB No. 3168 ........................................................................................................................... 4-15 Replacement .................................................................................................................................... 4-16

P Pg Sense Tube from AFCU to Reduction Gearbox .................................................................................... 4-104 Installation ........................................................................................................................................ 4-106 Removal ............................................................................................................................................ 4-105 Power Assurance Check .............................................................................................................................. 4-255 Power Lever (Ng) Controls ........................................................................................................................... 2-5 4-135 Description ....................................................................................................................................... 2-6 Inspection ......................................................................................................................................... 4-137 Installation ........................................................................................................................................ 4-138 Operation .......................................................................................................................................... 2-7 Removal ............................................................................................................................................ 4-136 Power Plant Change Procedures ................................................................................................................ 4-189 Power Plant Package ................................................................................................................................... 4-192 Installation ........................................................................................................................................ 4-195 Inspection ......................................................................................................................................... 4-194 Post Installation Inspection Procedures ....................................................................................... 4-196 Removal ............................................................................................................................................ 4-193 Power Plant Package Component Replacement ....................................................................................... 4-6 Installation......................................................................................................................................... 4-9 Reduction Gearbox Oil Filters and Oil Pressure Transmitter ...................................................... 4-7 Removal............................................................................................................................................. 4-8 Power Section ............................................................................................................................................... 2-3 Description ....................................................................................................................................... 2-4 Power Section Oil Pressure Check Adjustment ........................................................................................ 4-267


Index-8 Change 5


P (Continued) Power Turbine (Nf) Governors ..................................................................................................................... 4-64 Cleaning Nf Governor Orifice ......................................................................................................... 4-66 Installation ........................................................................................................................................ 4-67 Removal ............................................................................................................................................ 4-65 Power Turbine Governor Matching ............................................................................................................. 4-259 Preliminary Automatic (AFCU) to Manual Fuel Control (MFCU) Rigging ............................................... 4-243 Rigging – Power Lever Controls .................................................................................................... 4-245 Rigging – Droop Compensator Controls ...................................................................................... 4-246 Pressure Fueling Pilot Valve ....................................................................................................................... 4-220 Installation ........................................................................................................................................ 4-222 Removal ............................................................................................................................................ 4-221 Pressure Fueling Shutoff Valve .................................................................................................................. 4-223 Installation ........................................................................................................................................ 4-225 Removal ............................................................................................................................................ 4-224 Pressure Fueling Valve Assembly............................................................................................................... 4-217 Installation......................................................................................................................................... 4-219 Removal............................................................................................................................................. 4-218 Pressure Oil Sense Line to Check and Relief Valve ................................................................................. 4-95 Installation ........................................................................................................................................ 4-97 Removal ............................................................................................................................................ 4-96 Pressure Oil Tube From Reduction Gearbox ............................................................................................ 4-86 Installation ........................................................................................................................................ 4-88 Removal ............................................................................................................................................ 4-87 Pressure Oil Tube to Oil-To-Fuel Heater ..................................................................................................... 4-101 Installation ........................................................................................................................................ 4-103 Removal ............................................................................................................................................ 4-102 Pressure Oil Tube to Reduction Gearbox .................................................................................................. 4-92 Installation ........................................................................................................................................ 4-94 Removal ............................................................................................................................................ 4-93 Pumps – Fuel ................................................................................................................................................ 4-36 Installation ........................................................................................................................................ 4-38 Removal ............................................................................................................................................ 4-37 P3 Tube from AFCU to Gas Generator Case ............................................................................................... 4-73 Installation ........................................................................................................................................ 4-75 Pressure Testing Air Supply Systems .......................................................................................... 4-76 Removal ............................................................................................................................................ 4-74 P3 Tube to Reduction Gearbox .................................................................................................................... 4-77 Installation ........................................................................................................................................ 4-79 Removal ............................................................................................................................................ 4-78

Q Quality Assurance ........................................................................................................................................ 1-13


Change 4 Index-9


R Record of Applicable Technical Directives ................................................................................................ 1-11 Reduction Gearbox Oil Filters ..................................................................................................................... 4-7 Installation ........................................................................................................................................ 4-9 Removal ............................................................................................................................................ 4-8 Reduction Gearbox (RGB) Oil Pressure Adjustment ................................................................................ 4-260 Reduction Gearbox Oil Pressure Transmitter ........................................................................................... 4-7 Installation ........................................................................................................................................ 4-9 Removal ............................................................................................................................................ 4-8 Repair of Cracked Ceramic ITT Terminal Block ........................................................................................ 4-134 Rubber Sheath Replacement – Insulated and Heated Tubes ................................................................... 4-110 Testing ............................................................................................................................................... 4-111

S Scavenge Oil Tube ........................................................................................................................................ 4-89 Installation ........................................................................................................................................ 4-91 Removal ............................................................................................................................................ 4-90 Scope and Arrangement of Maintenance Instruction Manual .................................................................. 1-3 Screen - Compressor Inlet – Prior to PPC No. 9A ..................................................................................... 4-48 Installation ........................................................................................................................................ 4-50 Removal ............................................................................................................................................ 4-49 Seal – Accessory Drive ................................................................................................................................ 4-17 Replacement of Fuel Pump Drive Seal .......................................................................................... 4-18 Replacement of Starter-Generator Drive Seal .............................................................................. 4-19 Replacement of Ng Tachometer-Generator Drive Seal ................................................................ 4-20 Replacement of Nf Tachometer-Generator Drive Seal ................................................................. 4-22 Replacement of Blower Drive – Drive Seal ................................................................................... 4-23 Replacement of Power Turbine Governor Drive Seal ................................................................... 4-21 Sensing and Trim Cables to ITT Limiter Unit ............................................................................................. 4-129 Installation (Post PPC No. 76) ........................................................................................................ 4-133 Installation (Pre-PPC No. 76) .......................................................................................................... 4-132 Removal (Post PPC No. 76) ............................................................................................................ 4-131 Removal (Pre-PPC No. 76) .............................................................................................................. 4-130 Solenoids – Idle Stop ................................................................................................................................... 4-139 Installation ........................................................................................................................................ 4-141 Removal ............................................................................................................................................ 4-140 Spark Igniters ................................................................................................................................................ 4-45 Installation ........................................................................................................................................ 4-47 Removal ............................................................................................................................................ 4-46 Starter-Generator .......................................................................................................................................... 4-183 Buildup ............................................................................................................................................. 4-187 Description ....................................................................................................................................... 4-184 Installation ........................................................................................................................................ 4-188 Maintenance ..................................................................................................................................... 4-185 Removal ............................................................................................................................................ 4-186 Support Equipment ...................................................................................................................................... 1-7 System Interconnect Valve .......................................................................................................................... 4-214 Installation ........................................................................................................................................ 4-216 Removal ............................................................................................................................................ 4-215


Index-10 Change 5


T Topping Check .............................................................................................................................................. 4-256 Torque Control .............................................................................................................................................. 4-68 Installation ........................................................................................................................................ 4-72 Removal ............................................................................................................................................ 4-69 Torque Control Unit Priming – Prior to PPC No. 70 ..................................................................... 4-70 Torque Control Unit Priming – Incorporating PPC No. 70 .......................................................... 4-71 Torque Control Unit Maximum Torque Limit Check and Adjustment (AFC 363 aircraft)....................... 4-258 Torque Control Unit Maximum Torque Limit Check and Adjustment (Pre-AFC 363 aircraft)................ 4-258A Torque Control Unit Equalizing Function Check ....................................................................................... 4-258B Torque Pressure Oil Tubes .......................................................................................................................... 4-80 Installation ........................................................................................................................................ 4-82 Removal ............................................................................................................................................ 4-81 Transmitter – Reduction Gearbox Oil Pressure ........................................................................................ 4-7 Installation ........................................................................................................................................ 4-9 Removal ............................................................................................................................................ 4-8 Troubleshooting Power Plant and Related Systems ................................................................................ 4-1 Description ....................................................................................................................................... 4-2 Compressor Stall ............................................................................................................................. 4-3 Low Power/Low Torque .................................................................................................................. 4-4 Trouble Areas ................................................................................................................................... 4-5 Tubes – Fuel Transfer .................................................................................................................................. 4-112 Installation ........................................................................................................................................ 4-114 Removal ............................................................................................................................................ 4-113 Tubes – Insulated and Heated ..................................................................................................................... 4-107 Minor Repair ..................................................................................................................................... 4-109 Tubes – Insulated and Heated – Rubber Sheath Replacement ............................................................... 4-110 Testing .............................................................................................................................................. 4-111 Tube - Oil – Accessory Gearbox Pressure ................................................................................................. 4-98 Installation ........................................................................................................................................ 4-100 Removal ............................................................................................................................................ 4-99 Tube - Oil – From Reduction Gearbox ........................................................................................................ 4-86 Installation ........................................................................................................................................ 4-88 Removal ............................................................................................................................................ 4-87 Tube - Oil – No. 2 Bearing Scavenge .......................................................................................................... 4-83 Installation ........................................................................................................................................ 4-85 Removal ............................................................................................................................................ 4-84 Tube – Oil-To-Fuel Heater Pressure ........................................................................................................... 4-101 Installation ........................................................................................................................................ 4-103 Removal ............................................................................................................................................ 4-102 Tube - Oil – Pressure to Reduction Gearbox ............................................................................................. 4-92 Installation ........................................................................................................................................ 4-94 Removal ............................................................................................................................................ 4-93 Tube – P3 from AFCU to Gas Generator Case ............................................................................................ 4-73 Installation ........................................................................................................................................ 4-75 Pressure Testing Air Supply Systems .......................................................................................... 4-76 Removal ............................................................................................................................................ 4-74


Change 5 Index-11/(Index-12 blank)


T (Continued) Tube - Pg Sense – From AFCU to Reduction Gearbox .............................................................................. 4-104 Installation ........................................................................................................................................ 4-106 Removal ............................................................................................................................................ 4-105 Tube - Oil – Scavenge ................................................................................................................................. 4-89 Installation ........................................................................................................................................ 4-91 Removal ............................................................................................................................................ 4-90 Tube - Oil – Torque Pressure ..................................................................................................................... 4-80 Installation ........................................................................................................................................ 4-82 Removal ............................................................................................................................................ 4-81

V Valve – Combustion Chamber Drain ........................................................................................................... 4-60 Cleaning ............................................................................................................................................ 4-62 Installation ........................................................................................................................................ 4-63 Removal ............................................................................................................................................ 4-61 Valve – Compressor Bleed .......................................................................................................................... 4-268 Installation ........................................................................................................................................ 4-272 Removal ............................................................................................................................................ 4-271 Test Procedures-PPC 86 ................................................................................................................. 4-269 Test Procedures-Pre-PPC 86 .......................................................................................................... 4-270 Valve – Fuel Shutoff ...................................................................................................................................... 4-211 Valve – Pressure Fueling .............................................................................................................................. 4-217 Installation ........................................................................................................................................ 4-219 Removal ............................................................................................................................................ 4-218 Valve – Pressure Fueling Shutoff ................................................................................................................ 4-223 Valve – System Interconnect ........................................................................................................................ 4-214 Installation ........................................................................................................................................ 4-216 Removal ............................................................................................................................................ 4-215

W Warnings, Cautions and Notes ................................................................................................................... 1-17 Wet Motoring Run ......................................................................................................................................... 4-261

01-110hce-2-3 power plants and related systems.pdf

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