1646605-1800srm1300-(06-2006)-uk-en

BRAKE SYSTEMYARDMASTER®

HR45-27, HR45-31, HR45-40S, HR45-36L,HR45-40LS, HR45-45LSX [C227]

PART NO. 1646605 1800 SRM 1300

SAFETY PRECAUTIONSMAINTENANCE AND REPAIR

• When lifting parts or assemblies, make sure all slings, chains, or cables are correctlyfastened, and that the load being lifted is balanced. Make sure the crane, cables, andchains have the capacity to support the weight of the load.

• Do not lift heavy parts by hand, use a lifting mechanism.

• Wear safety glasses.

• DISCONNECT THE BATTERY CONNECTOR before doing any maintenance or repairon electric lift trucks. Disconnect the battery ground cable on internal combustion lifttrucks.

• Always use correct blocks to prevent the unit from rolling or falling. See HOW TO PUTTHE LIFT TRUCK ON BLOCKS in the Operating Manual or the Periodic Mainte-nance section.

• Keep the unit clean and the working area clean and orderly.

• Use the correct tools for the job.

• Keep the tools clean and in good condition.

• Always use HYSTER APPROVED parts when making repairs. Replacement partsmust meet or exceed the specifications of the original equipment manufacturer.

• Make sure all nuts, bolts, snap rings, and other fastening devices are removed beforeusing force to remove parts.

• Always fasten a DO NOT OPERATE tag to the controls of the unit when making repairs,or if the unit needs repairs.

• Be sure to follow the WARNING and CAUTION notes in the instructions.

• Gasoline, Liquid Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Diesel fuelare flammable. Be sure to follow the necessary safety precautions when handling thesefuels and when working on these fuel systems.

• Batteries generate flammable gas when they are being charged. Keep fire and sparksaway from the area. Make sure the area is well ventilated.

NOTE: The following symbols and words indicate safety information in thismanual:

WARNINGIndicates a condition that can cause immediate death or injury!

CAUTIONIndicates a condition that can cause property damage!

Brake System YardMaster® Table of Contents

TABLE OF CONTENTS

General ............................................................................................................................................................... 1Service Brakes ............................................................................................................................................... 2Parking Brake................................................................................................................................................ 4Brake Cooling System ................................................................................................................................... 4

Accumulator Replacement................................................................................................................................. 7Parking Brake Caliper Repair .......................................................................................................................... 7

Remove ........................................................................................................................................................... 7Disassemble ................................................................................................................................................... 7Clean .............................................................................................................................................................. 8Inspect ............................................................................................................................................................ 9Assemble ........................................................................................................................................................ 10Install and Adjust .......................................................................................................................................... 10

Service Brake Assembly Repair ........................................................................................................................ 10Remove ........................................................................................................................................................... 10Disassemble ................................................................................................................................................... 10Clean .............................................................................................................................................................. 11Inspect ............................................................................................................................................................ 11Assemble ........................................................................................................................................................ 12Install ............................................................................................................................................................. 12

Brake System Air Removal ............................................................................................................................... 12Service Brakes Wear Check............................................................................................................................... 12Relief Valve Adjustment for Fan Drive............................................................................................................. 13Troubleshooting.................................................................................................................................................. 13

This section is for the following models:

HR45-27, HR45-31, HR45-40S, HR45-36L, HR45-40LS, HR45-45LSX [C227]

©2007 HYSTER COMPANY i

"THEQUALITYKEEPERS"

HYSTERAPPROVEDPARTS

1800 SRM 1300 General

GeneralThis section describes the operation and replacementprocedures for some components of the park brakeand service brake system. See Figure 1.

Repair of the oil cooled service brakes are describedseparately in Service Brake 1800 SRM 1038.

1. AXLE HOUSING2. COOLING OIL RETURN LINE3. BRAKING PRESSURE LINE4. PISTON5. BRAKE HOUSING6. RETURN SPRING7. STATIONARY DISCS

8. FRICTION (ROTATING) DISCS9. AXLE SHAFT10. SPINDLE11. HUB12. COOLING OIL13. COOLING OIL SUPPLY

Figure 1. Service Brake

1

General 1800 SRM 1300

SERVICE BRAKES

At each drive wheel is an oil cooled brake assem-bly. The brake assembly has friction discs that rotatewith the wheel, and stationary discs that are con-nected with the axle housing. A piston, moved by oilpressure from the brake system, pushes the discs to-gether for braking. A separate oil system circulatesoil through the sealed case to cool the discs, whichare heated during braking. See Figure 1.

Oil pressure for the service brake system is suppliedby port ACC2 of the L90LS valve, which directly con-nects with an accumulator. See Figure 2. Maxi-mum brake oil pressure is 200 bar (2901 psi). Afully charged accumulator allows applying the ser-vice brakes a few times, in case oil pressure sup-ply is interrupted, for instance when the engine is

stalled. The accumulator is fully charged at 175 bar(2538 psi) or higher. The accumulator is empty at145 bar (2103 psi) or lower.

Oil pressure is admitted to the service brakes bythe brake relay valve. Another accumulator is fittedclose to the relay valve for immediate response. Thebrake relay valve receives pilot oil from the brakepedal valve, when the brake is depressed.

When the brake pedal is moved, micro-switch S139sends a signal to the APC200 transmission controlsystem to declutch the transmission. When the re-lay valve has admitted more than 5 bar (72.5 psi) oilpressure to the service brakes, pressure switch S17will switch on the brake lights.

Figure 2. Brake System (Sheet 1 of 2)

2


1. BRAKE PEDAL VALVE2. BRAKE RELAY VALVE3. PARK BRAKE CALIPER

4. SERVICE BRAKE5. SERVICE BRAKE ACCUMULATOR6. L90LS ACCUMULATOR

Figure 2. Brake System (Sheet 2 of 2)

3


PARKING BRAKE

The parking brake system uses a disc brake that isinstalled on the rear of the differential. See Figure 2.The spring applied caliper is installed on the differ-ential housing and the brake disc is fitted on the pin-ion shaft. When the brake caliper is pressurized, oilwill move the piston against spring pressure, caus-ing the parking brake to release.

The operation of the parking brake is controlled bysolenoid valve E227, which is fitted on the L90LSvalve. When solenoid E227 is not activated, parkingbrake pressure is drained to the tank, causing theparking brake to apply. When solenoid E227 is acti-vated, oil pressure will release the parking brake.

Solenoid E227 is primarily controlled by the park-ing brake switch on the instrument panel. E227 willalways deactivate when the key switch is turned toOFF.

E227 will NOT deactivate when a gear is selectedwhile the engine is still running. E227 can alwaysbe activated by applying the parking brake switch.

Port ACC2M in the L90LS valve has pressure switchS77 that sends a signal to the APC200 transmissioncontroller when a pressure of 105 bar (1523 psi) hasbeen reached.

BRAKE COOLING SYSTEM

The brake cooling system is a separate system witha separate oil tank. The 12 cc brake cooling pump

provides a continuous flow of oil through the brakeradiator, brake filter, and service brakes. The radia-tor for the brakes is included in an assembly togetherwith the radiator for the hydraulic system. The ra-diator assembly has a fan motor, driven by the 12 ccbrake cooling pump. See Figure 3.

When the radiator assembly is cold, oil in the brakecooling system mainly flows through the radiator.Due to the low resistance of the cooler, only some ofthe oil follows the parallel line through the fan mo-tor. This will cause the fan to always turn at somespeed, when the engine is running.

When either temperature switch (S86 and/or S87) inthe radiator assembly for brakes and hydraulic lineshas activated solenoid E13, the brake cooling oil isforced to first pass the fan motor and then the brakeradiator. An initially slow fan speed will result ina pressure peak at sudden closure of solenoid E13.To absorb this pressure peak, the 100 bar (1450 psi)relief valve opens and allows a gradual increase ofthe fan speed.

The bypass valve in the line leading to the fan mo-tor is to prevent cavitation in case the engine speeddrops quickly, while the quickly rotating fan tends toremain at the same speed.

The bypass valves fitted in the radiators protect themagainst too high of pressures.

4


Figure 3. Brake Cooling System (Sheet 1 of 2)

5


A. TO DRIVE AXLE B. TO HYDRAULIC FILTER

1. 12 CC BRAKE COOLING PUMP2. 40 CC HYDRAULIC COOLING PUMP3. PORT T14. PORT P15. SOLENOID VALVE E136. PORT A7. PORT 28. 100 bar (1450 psi) RELIEF VALVE

9. BYPASS VALVE10. PORT T211. 10 bar (145 psi) RADIATOR BYPASS VALVE12. HYDRAULIC MOTOR13. FAN MOTOR14. BRAKE RADIATOR15. 5 bar (72.5 psi) RADIATOR BYPASS VALVE16. BRAKE FILTER

Figure 3. Brake Cooling System (Sheet 2 of 2)

6

1800 SRM 1300 Parking Brake Caliper Repair

Accumulator Replacement

WARNINGThe accumulator has a pressure charge andcan cause an injury if the pressure is releasedtoo fast. Follow the manufacturer’s instruc-tions during removal and installation.

Before disconnecting any hydraulic lines, re-lease pressure from the hydraulic circuit as fol-lows:• Shut off the engine and completely lower the

boom. Install blocks at the wheels to preventthe vehicle from moving.

• Operate the brake pedal until the hydraulicpressure is released.

1. Put tags for identification on the lines. Slowlydisconnect hydraulic lines from accumulator torelease any pressure slowly. Put caps on openlines. Remove accumulator.

2. Follow the manufacturer’s instructions duringinstallation of the new accumulator. Tightenbracket nuts. Connect lines. Pre-charge thebrake accumulator to 100 bar (1450 psi).

3. Operate system and check for leaks.

Parking Brake Caliper RepairREMOVE

1. Put blocks in front and back of tires so vehiclecannot move. See Figure 4.

2. Remove cotter pin and tighten nut to releaseparking brake. See Figure 5.

WARNINGBefore disconnecting any hydraulic lines, re-lease pressure from the hydraulic circuit as fol-lows:• Shut off the engine and completely lower the



3. Release pressure from accumulator. Disconnecthydraulic line at caliper. Put cap on open line.

WARNINGBrake linings can contain dangerous fibers.Breathing the dust from these linings can

be a cancer or lung disease hazard. Do notmake dust! Do not clean brake parts withcompressed air or by brushing. Use vacuumequipment approved for brake dust or followthe cleaning procedure in this section. Whencalipers are removed, do not make dust.

Do not sand, grind, chisel, hammer, or changelinings in any way that will make dust. Anychanges to linings must be done in a restrictedarea with special ventilation. Protective cloth-ing and a respirator must be used.

4. Remove pins that hold caliper to bracket. Re-move caliper and brake linings.

DISASSEMBLE

1. Remove nut from stud. See Figure 5. Care-fully remove cover from caliper housing. Removewashers and springs from housing.

2. Pull piston from bore.

7

Parking Brake Caliper Repair 1800 SRM 1300

1. CALIPER MOUNT2. OIL SEAL3. ROTOR FLANGE

4. ROTOR5. NUT AND WASHER6. CALIPER ASSEMBLY

Figure 4. Parking Brake Assembly

CLEAN

1. Do not release brake lining dust from brake lin-ings into air.

2. Use a solvent approved for cleaning of brakeparts to wet the brake lining dust. Follow in-structions and cautions of manufacturer for useof the solvent. If a solvent spray is used, sprayat a distance so dust is not released into air.

3. When brake lining dust is wet, clean parts. Putany cloth or towels in a plastic bag or an airtightcontainer while they are still wet. Put a DAN-GEROUS FIBERS warning label on plastic bagor airtight container.

4. Any cleaning cloths that will be washed must becleaned so brake lining fibers are not releasedinto air.

8

1800 SRM 1300 Parking Brake Caliper Repair

1. CALIPER HOUSING2. BRAKE LINING (2)3. ALIGNMENT PIN (2)4. BACKUP RING5. O-RING6. PISTON7. WASHER

8. SPRING9. SPRING COVER10. STUD11. WASHER12. NUT13. COTTER PIN

Figure 5. Parking Brake Caliper

INSPECT

Inspect parts and bores for scratches. If there arescratches or other damage, replace damaged parts.Inspect rotor as shown in Figure 6.

Legend for Figure 6

1. MAXIMUM ROTOR WEAR 1.5 mm (0.06 in.)2. MINIMUM ROTOR THICKNESS 17.0 mm

(0.67 in.)3. ROTOR THICKNESS 20.07 mm (0.79 in.)

Figure 6. Inspect Rotor for Parking BrakeCaliper

9

Service Brake Assembly Repair 1800 SRM 1300

ASSEMBLE

1. Lubricate piston with clean hydraulic oil. SeeFigure 5. Install O-rings and backup rings onpiston. Install piston in housing.

2. Install washers and spring assembly in housing.Install spring cover in housing.

3. Install washer and nut on stud. Tighten nut toretract piston.

INSTALL AND ADJUST

1. Install caliper on bracket. Install alignmentpins, O-rings, and cotter pins. See Figure 4 andFigure 5.

2. Connect hydraulic line to caliper. Loosen nut.See Figure 5.

3. Remove air from brake system as described inBrake System Air Removal. Check for leaks.

4. Adjust brake linings as follows:

a. Put blocks in front and back of tires so vehiclecannot move.

b. Start engine and release parking brake (ap-ply hydraulic pressure). Check that calipermoves freely on alignment pins.

c. Slide caliper so one of the brake linings isagainst the brake rotor. Measure clearancebetween brake lining and rotor. If clearanceis more than 3.4 mm (0.13 in.), continue withadjustment procedures.

d. Turn nut until it just touches spring cover.Apply parking brake (release hydraulic pres-sure).

e. Turn spring cover clockwise (tighten) untilboth linings touch rotor. Turn spring covercounterclockwise 1-1/2 turns, then measureclearance between lining and rotor. Turnspring cover as necessary to obtain correctclearance of 2.2 mm (0.090 in.).

f. Release parking brake. Loosen nut and in-stall cotter pin.

Service Brake Assembly RepairThe service brake assemblies are a part of the hub ofthe drive axle. Most repairs are seal replacement atthe hub and brake housing. Replace these seals anytime the hub is removed.

NOTE: See Service Brakes Wear Check for the proce-dures to check the friction discs for wear.

REMOVE

1. Put blocks in front and back of steer tires so ve-hicle cannot move.

WARNINGCompletely remove the air pressure from thetires before removing the wheels from the ve-hicle. Air pressure in the tires can cause thetire and rim parts to explode causing seriousinjury or death.

Always wear safety glasses.

2. Remove drive wheel and hub as described in thesection for Drive Axle.

WARNINGBefore disconnecting any hydraulic lines, re-lease pressure from the hydraulic circuit as fol-lows:• Shut off the engine and completely lower the



3. Disconnect hydraulic line for piston and the twohydraulic lines for cooling oil. Put caps on allopen lines and ports.

4. Remove mount bolts and carefully slide brake as-sembly off spindle.

DISASSEMBLE

NOTE: It is not necessary to disassemble brake as-sembly to replace seals. Make sure all brake oper-ating pressures are correct before replacing internalparts of assembly. Incorrect operation is usually dueto other parts of the brake system.

10

1800 SRM 1300 Service Brake Assembly Repair

If necessary, disassemble service brake assembly asshown in Figure 7.

CLEAN

Make sure all loose material is cleaned out of hous-ing.

INSPECT

Check all parts for wear or damage. Check liningmaterial on disc for wear that is not even and forcracks or missing pieces. This inspection can indicatethe wear rate of the service brakes.

1. PLUG AND O-RING2. BOLT3. WASHER4. COVER5. BLEEDER SCREW6. FITTING7. SEAL8. SPRING

9. PISTON10. DISC, STATIONARY (1)11. DISC, FRICTION (10)12. DISC ASSEMBLY13. SPACER14. HOUSING15. PLUG WITH ROD OR ROLL PIN16. GUIDE

Figure 7. Service Brakes

11

Service Brakes Wear Check 1800 SRM 1300

ASSEMBLE

CAUTIONMake sure to align all of the movable discs sothat they will fit on the hub correctly. Makesure all the stationary discs are correctly in-stalled in the housing. Damage to the discs willoccur during installation if the discs are notcorrectly aligned.

Assemble service brake assembly as shown in Fig-ure 7. Always use a new set of discs and use only newseals and gaskets. Make sure to assemble discs sostationary and rotating discs alternate in disc pack.Make sure to tighten cover bolts in an alternate pat-tern so cover fits on housing evenly.

INSTALL

Use new seals on spindle and between hub and as-sembly housing. See Figure 1. Lubricate new sealsand seal surface with clean oil. Carefully install ser-vice brake assembly on spindle. Carefully install hubon spindle so splines of hub align with rotating discs.Do NOT try to force hub into service brake housing.Minor rotation can help splines and discs align cor-rectly. Install remainder of drive axle parts as de-scribed in the section for the Drive Axle. Installbrake lines as removed during Removal procedure.Remove air from brake system as described in BrakeSystem Air Removal. Check for leaks.

Brake System Air Removal

WARNINGRemove air from the brake system after eachinstallation or repair of hydraulic or brake sys-tem components or hydraulic lines. The brakeswill not operate correctly with air in the systemand can cause injury or damage.

1. Fill hydraulic tank to correct level. Operateengine to charge accumulator to maximum pres-sure. Keep engine operating at idle speed tomaintain pressure. Push brake pedal severaltimes to fill brake system.

2. Connect one end of hose to special fitting onbrake housing. Put other end of hose in con-tainer filled with clean hydraulic fluid.

3. To remove air, loosen fitting and have a helperoperate brake pedal until no air is seen comingout of hose in container. Tighten fitting after airstops coming out and before disconnecting hose.Connect hose at each of the following points:• Special fittings at each wheel brake assembly• Special fitting at the parking brake caliper

4. Do Step 2 and Step 3 again after a wait of approx-imately 2 hours to remove the last of the air.

Service Brakes Wear CheckCheck friction discs for wear by measuring stroke ofpiston. See Figure 8.

1. Run engine to load accumulator for brake systemto a normal level.

2. Stop engine and apply parking brake. Put blockson both sides of drive tires to prevent movementof truck.

3. Remove outlet tube for brake cooling system. Theoutlet fittings are at the front side of the driveaxle.

4. Measure distance from edge of fitting to face ofpiston. This dimension will be just less than127 mm (5.0 in.).

5. Have helper push and hold down brake pedal toactivate service brakes.

12

1800 SRM 1300 Troubleshooting

6. Check measurement between fitting and pistonagain. The difference between the two measure-ments is the stroke of the piston. The strokewith new brake parts is 3.4 to 6.8 mm (0.134 to0.269 in.). When the stroke is more than 13.3 mm(0.525 in.), the friction discs need to be replaced.

7. Check the other service brake assembly.

8. Connect oil lines and remove air from brake sys-tem.

1. OUTLET FITTING2. STROKE

DISTANCE

3. PISTON

Figure 8. Measure Service Brakes for Wear

Relief Valve Adjustment for Fan DriveAdjust the relief valve for the fan drive as follows:

1. Install a 250 bar (3626 psi) gauge at port P2.

2. Run engine at full throttle and bypass one ofthe temperature switches on the radiator (S86 orS87) and observe the pressure gauge reading. So-lenoid E13 will switch ON and allow pump oil topass through the fan motor only. Highest pres-sure will be achieved during initial start up ofthe fan.

3. Adjust relief pressure to 100 bar (1450 psi) byremoving the cap on the valve and turn theadjustment screw in to increase the pressure, orturn the screw out to lower the relief pressure.Measure the relief pressure several times byfirst switching the fan OFF, rev the engine tofull throttle and bypass the temperature switchagain.

Troubleshooting

PROBLEM POSSIBLE CAUSE PROCEDURE OR ACTION

The brakes do not stop thevehicle.

The linings are worn or damaged. Replace brake linings.

There is not enough hydraulic pres-sure in the system.

Check brake system pressure.

The brake lines have a restriction. Check and replace brake lines.

The accumulator is damaged. Install new accumulator.

13

Troubleshooting 1800 SRM 1300


The brakes apply slowly. There is not enough hydraulic pres-sure in the system.

Check brake system pressure.

The brake line(s) have a leak or re-striction.

Check and replace brake lines.

Brake pedal(s) goes to thefloor.

There is air in the brake system. Remove air from brake system.

There is a leak(s) in a brake line. Check and replace brake lines.

The service brakes do not op-erate equally.

The linings are worn or damaged. Replace brake linings.

The brake line(s) have a restriction. Check and replace brake lines.

The brake(s) does not re-lease.

The brake linings are damaged. Replace brake linings.

A brake line has a restriction. Check and replace brake lines.

The parking brake is applied. Check operation of parking brake.

Service brakes do not oper-ate when the engine is notrunning.

There is no charge in the accumula-tor.

Check oil supply to brake pedal valve.

Hydraulic lines for the accumulatorcircuit leak or have restrictions.


The parking brake does notrelease.

The hydraulic pressure is too low. Check oil supply to brake pedal valve.

There is a leak(s) in the hydrauliclines.


The parking brake valve is damaged. Install new valve.

The parking brake caliper is dam-aged.

Repair or replace brake caliper.

14

1800 SRM 1300 Troubleshooting


The parking brake will notapply.

The springs in the brake caliper aredamaged.

Install new springs.

The brake caliper is not adjusted cor-rectly.

Check and adjust caliper.

The brake linings are worn or dam-aged.

Replace brake linings.

The brake rotor is worn or damaged. Repair or replace brake rotor.

Accumulator fails to startcharging.

The relief valve in the brake pedalvalve does not work correctly.

Check and repair relief valve.

The line to the accumulator has a re-striction.


15

NOTES

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

____________________________________________________________

16

TECHNICAL PUBLICATIONS

1800 SRM 1300 6/06 Printed in United Kingdom

1646605-1800srm1300-(06-2006)-uk-en

Documents

unit clean

brake systemyardmasterhr45

working area clean

brake cooling system

unit needs repairs

safety information

flammable gas

safety precautionsmaintenance