Engine lubrication system 18

18 Engine lubrication system

Job No.

Oil circuit, oil pressure, overpressure and bypass valve ................... ....... 18 - 005Measuring oil consumption ....................................... ....... 1 8 - 0 2 5Removal and installation of oil filter ................................. ........ - 110Removal and installation of oil pump ................................ ........ - 210Removal and installation of oil overpressure valve ...................... ........ - 215Checking oil level indicator ....................................... ........ - 220Function of low engine oil level indicator ............................. ........ - 225

181

.,.........,......._._,__................ __I~.I~-..Y_.~.~.-YYY)YLYI

18-005 Oil circuit, oil pressure, overpressure and bypass valve, oil filter

Oil circuit

190 160

pl6 - 0 0 7 2 - 5 6

18.09-00511

P18-0073-56A

1 4 011 overpressure valve 6 0 011 pipe1 6 011 pump 1 6 0 Camshaft51 Oil filter 1 9 0 Idler gear shaft52 011 pressure gauge

PlB-5179.33A

Viscosity grades for engine oils according to SAE

Adhering to the SAE grades in accordance with ambient temperatures would result in frequent orlchanges. Consequently, the temperature ranges are merely guidelines, which can be exceeded in theupper or lower limrts for brief periods.In moderate climatic zones SAE 30 may be used from the spring on for all engine models. SAE low-40or SAE IOW-50 may be used as an all-seasons 011 for all gasoline engines.

18.09-005!2

Oil capacity in liters (approved engine oils see Service Product Specifications).

Engine (total capacity when refilling) 5,s

Engine capacity when changing oil and filter 5,o

Oil sump, max.!min. 4,8i2,8

Opening pressures of oil overpressure and oil filter element bypass valve bar gauge pressure

Oil overpressure valve in timing case cover 4,5-0,8

Oil filter element bypass valve in oil filter (difference pressure) 35

Function of oil circuit

The oil is drawn off at the lowest point of the oilsump through the strainer basket and the oilsuction pipe (7) to the suction chamber (B) andpumped into the tooth gaps, which producepressure chamber (A) as a result of theeccentric arrangement of the oil pump gears (1and 2).

To ensure that the oil remains in the tooth gapson its way from the suction to the pressurechamber, a sickle (a) is attached between bothgears in this area.

1 Inner 011 pump gear2 Outer 011 pump gear3 Oil pump cover7 Suction pipe11 M6 x30 bolt (9 off)lla Ton: bolt14 Overpressure valve15 Compression spnng16 Screw plug17 Seal22 Dnve sleeve44 Timing case cover

Pressure chamberSuction chamberDamplng chamberSickleTo 011 filter

vtie l la

0- _ - i - - 4 4

W\fa h\\\ \\ \ 1

P18-0033-35A

16.09-005 3

The teeth mesh again at the end of thepressure chamber and force the oil out of thetooth gaps.

The oil flows from the pressure chamber (A)along the feed passage (d) in the timing casecover and crankcase to the oil filter.

Pressure chamber (A) and vacuum chamber (6)are linked by the oil overpressure valve.

From an oil overpressure of approx. 4 bar, thepiston (14) of the oil overpressure valve ispushed against the force of the compressionspring (15) and opens the relief cross-section,through which part of the oil flows back to thesuction chamber (B), depending on oil pressure.

As the piston (14) is moved, the oil in chamber(C) is displaced and flows through the reliefgrooves on the outside of the piston to thesuction chamber (B).

1234567691011121314151617A0

011 filter bottom sectionReplaceable cartrrdgeConnectron fittingValve coneCompressron springSpring plateLocking nngFalter elementValve plateValve plate carrrerCompressron springValve holderCompressron springSpring plateRubber diaphragmContact-pressure plateSealFeed from 011 pumpUnfiltered 011 to mam oilgalleryFaltered oil to mam 011galleryConnectron for electrical oilpressure sensor

Oil filterThe oil coming from the feed passage (A) flowsthrough the feed and discharge hose in thecontact-pressure plate (16) into the replaceablecartridge.

As a result of the oil pressure, the rubberdiaphragm (15) is raised and the oil flowsthrough the filter element (8) from the outside tothe inside (arrows).

On the inside, the valve plate (9) is opened as aresult of the pressure of the filtered oil. The oilflows through the connection fitting (3) to thegallery (C) and on to the main oil gallery in thecrankcase.

C

D

18 09.005,4

The two check valves (9-12 and 13-16) preventthe filter cartridge from running empty when theengine is switched off and when changing thefilter.

The bypass valve (4-7) opens when thedifference pressure between dirty and clean oilside exceeds 3 bar. This is the case if the filterelement is severely fouled. The oil then flowsthrough the gallery (B) unfiltered to the main oilgallery.

When changing the filter, a slight quantity of oilflows out of the replaceable cartridge despite thecheck valves, which flows together with oil fromthe bottom of the oil filter along the galleries (Aand C) to the engine.

Oil supply of chain tensionerThe oil flows through a passage which branchesoff vertically up the way at the front of the mainoil gallery, to the cylinder head, flows in a crossgroove (arrow) to a vertical feed passage incrankcase and on to the chain tensioner.

1363738394041ab

CrankcaseChain tensioner housingThrust pinDetent spnngCompresston spnngCap nutSealFeed passage 1 .l mm dia.Restnction passage 1.2 mmdia.

1

41

40a

39

38

37

36

Lubrication of valve timingThe oil coming from the main oil gallery in thecrankcase, flows through a 4.5 mm dia. jet (A)installed in the cylinder head, and through theannular gap (arrows) direct to the longitudinalgallery (a) in the cylinder head (pressure-oriented oil feed). This oil supply system ensuresthat the oil pressure prevailing downstream ofthe oil filter depending on the operating state,always exists at the hydraulic valve clearancecompensating elements. In addition, the nozzle(A) serves as an oil return flow stop whichprevents the longitudinal passage (a) and thevalve clearance compensating elements running

dry.

I

Part of the oil flows through the restrictionpassage (g) with dia. of 2.5 mm and the twogrooves (arrows) in the rear rocker arm bearingbracket to the rear camshaft bearing and thereinto the hollow-drilled camshaft. The oil flowsthrough the camshaft to the other camshaftbearings (flow-oriented oil feed).

The rocker arm bearing points are lubricatedfrom the longitudinal passage (a) in the cylinderhead and the hydraulic valve clearancecompensating elements supplied with oil (b) fromthere through a passage in the rocker arm.

The cam lubrication is provided through the oilpipe (d) bolted to the rear camshaft bearing.

a

PO5-0160-13

r&09-005/6

Lubrication of idler gear shaft and ignitiondistributor drive

The oil flows from the front camshaft bearingthrough a cross passage to the left front cylinderhead bolt bore and from there along a crossgroove (e) to the feed passage in the crankcase.

The oil flows on to the rear bearing bush (17) ofthe idler gear shaft and through the hollow-drilledidler gear shaft (18b) to the front bearing bush(6) in the timing case cover (44).

The ignition distributor drive (18) is lubricated bysplash oil.

The cam (18d) which is press-fitted to the rearend of the idler shaft gear on engines102.9221924 (non-U.S.) and drives the fuelpump, is lubricated by the oil splash jet (13).

Oil return

Four return passages (arrows) are provided onthe righthand side of the cylinder head (lookingin direction of travel) for the oil return to thesump; part of the oil flows back through thechain box.

i 17 18dPOS-0089-13

PO,-2127-13

18.09-00517

In the crankcase, the oil flowing back is passedalong an oil collecting gallery (arrows) to the castreturn passage.From here, it flows into the oil pan.

Oil pressure and oil pressure gaugeAt normal operating temperature, the oil pressureat idling speed must drop to 0.3 bar gaugepressure.

When the accelerator is depressed, the oilpressure must immediately rise again and be atleast 3 bar gauge pressure at 3000 rpm.

The oil pressure gauge in the instrument clusteris actuated electrically by an oil pressure sensorwhich is bolted onto the oil filter housing (arrow).

FunctionWhen the ignition is switched on, the gauge inthe instrument cluster is constantly energized.Ground is applied in the gauge through thepressure sensor. As the pressure increases, theohm resistance of the pressure sensor increasesand thus alters the gauge reading.

Resistances of pressure sensor as a functionof oil pressure.

Pressure (bar) 0 1 2 3

Resistance approx. Sz 10 69 129 184

18.09-00518

Checking oil levelThe oil level depends, among other factors, onthe oil temperature and on the time for the oil toflow back after the engine is switched off. Forthis reason, do not measure oil level until approx.5 minutes after switching off the engine fromnormal operating temperature (approx. 80 “C oiltemperature).The dipstick must always be withdrawn andwiped off before checking the oil level.

To properly assess the oil level, the dipstickmust be viewed from both sides. Thedetermining factor is always the clear horizontalindication of the dipstick (arrow).

PlB-0082-15

18 09-0059

18-025 Measuring oil consumption

Special tools

NoteOil consumption should be calculated with thedipstick with millimeter graduations and therelated test sheet. It should not exceed 1.0Ii1000 km.

The procedure for measuring oil consumption isdescribed on the front of the test sheet. It isessential to properly observe this procedure.

Oil consumption indicated in mm on the dipstickshould be read off on the basis of the diagramon the rear of the test sheet in ems.

Ar CautionTo avoid any incorrect measurements, checkwhether the engine oil has been diluted with fuelbefore measuring oil consumption.

PO3-0137-17

18.09-025;l

18-110 Removal and installation of oil filter

Preceding work:Air filter removed (09-400 and 09-410).

J’ P18-0050-35A

Replaceable cartridge (1) . . . . . . . . . . . . . . . . . unbolt, bolt on, special tool103 589 02 09 00.

NoteTighten replaceable cartridge by hand, thentighten a further l/4 turns (90”) (step 2).

Plug (54) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . for oil pressure sensor, detach, plug in.

Oil filter base (2) . . . . . . . . . . . . . . . . . . . . . . . . unbolt, bolt on, tightening torque 25 Nm (step

4).Gasket (59) . . . . . . . . . . . . . . . . . . . . . . . . . . . replace.

Sealing surfaces . . . . . . . . . . . . . . . . . . . . . . . . clean, seal main oil gallery for this step, open(step 5).

Run engine . . . . . . . . . . . . . . . . . . . . . . . . . . . check for leaks.

18.09-110/l

Special tools

(JOI 5897221 ““Ij103589020909

NoteM 102 engines are equipped with an oil filter withreplaceable cartridge (disposable filter).When changing the filter, the replaceablecartridge is unscrewed and replaced with a newone.

The initial operation and continuous operationcartridges were of different sizes up to 5188.

The housing of oil pressure sensor has beenmodified to provide adequate clearance for thespeedometer shaft.

A Previous versionB Present version

A lnltlal operation replaceable cartridgeB Continuous operation replaceable cartndge

18.09-I 1012

Standard implementation: December 1984

Model Engine Engine end No.Man. trm. Autom. trm.

Vehicle ident end No.

Non-U.S. version vehicles 102.924 005181 001370 A 170601 F 063039102.962 016655 007928 F 063008

201.024 @ 102.985 000782 006991 F 066585

The initial operation oil filter replaceable cartridgehas been modified (same size as continuousoperation filter) to achieve standardization withengine 103.

Removal and installation

1 Remove and install air filter(09-400 and 09-410).

2 Remove and install oil filter replaceablecartridge, special tool 103 589 02 09 00.

NoteApply a light coating of oil to gasket (arrows)before installing the replaceable cartridge.

Screw on replaceable cartridge and tighten byhand.

Then tighten a further l/4 turns (90”) with thewrench socket.

18 09-11013

3 Disconnect plug (arrow) for oil pressuresensor, plug in.

4 Unscrew oil filter base section, screw on,tightening torque 25 Nm.

5 Clean sealing surfaces on oil filter andcrankcase.

For this purpose, seal the bores on thecrankcase, open (arrows).

6 Run engine, check for leaks.

18.09-11014

18-210 Removal and installation of oil pump

Preceding work:Timing case cover removed (01210).

PIE-0032-57

Oil pickup (7) with strainer basket . . . . . . . . . . . unbolt, bolt on, tightening torque 10 Nm (step

2).Gasket (12) . . . . . . . . . . . . . . . . . . . . . . . . , . . replace.

Oil pump cover (3) . . . . . . . . . . . . . . . . . . . . . . unbolt, bolt on, tightening torque 10 Nm (step3).

NoteRe-install Torx bolt at the same point (for spacereasons).

O-ring (10) . . . . . , . . . . . . . . . . . . . . . . . . . . . . replace.

Oil pump gears (1 and 2) . . . . . . . . . . . . . . . . . . remove, insert, oil.

Driver sleeve (22) , . . . . . . . . . . . . . . . . . , . , . . if removed, install before fitting timing casecover.

18 09-.210/l

Special tool

NoteThe two oil pump gears (1 and 2) are arrangedeccentrically in the timing case cover (44).

The oil pump gears (1 and 2) are driven by thedrive sleeve (22) which has two faces on theouter surface for this purpose and is attached bythe central bolt to the crankshaft, which alsoholds the vibration damper or the hub with beltpulley and the crankshaft gear on the crankshaft.

The bore of the driven, externally toothed gear(1) has the identical contour as the outer surfaceof the drive sleeve.

The oil pump gears are supplied asreplacement parts only together (rotor set).

The oil pump cover (3) is attached to the rear ofthe timing case cover (44). It is fixed in place onthe timing case cover (44) with a centeringsleeve.

18 09-21012

The sealing ring (12) seals the connection fittingat the oil pump cover (oil feed) to the oil passagein the crankcase.

The jump overlock for the timing chain is alsocast onto the oil pump cover.

Oil suction pipe together with oil strainer basketis bolted to the oil pump cover (13) with a gasket

(12).

The oil suction pipe with oil strainer basket isadditionally attached by means of a bracket (8)to the main bearing cover (arrows).

The timing case cover has been modified withthe installation of the double roller timing chain(as of November 1987).The contours on the rear have been lowered.

A Previous versionI3 Present version

In addition, it has a different rib pattern on thetop. The jump overlock (i) is wider and theconnection fitting (K) longer.

18.09-21013

The drive sleeve for oil pump is manufacturedfrom sintered metal, previously from steel.

Implementation: August through December 1985

Model Engine Engine end Nos. Engine end Nos. Vehicle ident end No.Man. trm. Autom. trm.

201.024 @ 102.985 002517-003158 002505028724 F 137963- ;F 182815. End of implementation not recorded.

2 mm wider pump gears (1, 2) are installed toimprove the delivery of the oil pump.

Sue “B” previously 7.5 mmnow 9.5 mm

18 09-210.‘4

Removal and installation

1 Timing case cover removed (01-210).

2 Unbolt oil pickup together with strainerbasket (7) bolt on. Replace gasket.

Tightening torque: 10 Nm

3 Unbolt oil pump cover, bolt on, replace O-ring (10).

Tightening torque:

Note

10 Nm

As of implementation of the flatter oil pumpcover, a Torx bolt (15) is installed for spacereasons.

Tightening torque: 10 Nm

4 Remove oil pump gears, insert, oil withengine oil for this purpose.

Caution!The oil pump gears may only be replaced as apair.

If the driver sleeve (22) has been removed, thiscan be inserted after installing the timing casecover.

18.09-210!5

5 Check oil level, adjust to correct level ifnecessary.

6 Run engine, check oil pressure and oil leaks.

l&09-210/6

18-215 Removal and installation of oil overpressure (bypass) valve

Preceding work:Removal and installation of V-belt (13-342).Removal and installation of V-belt tensioning device (13-345).

Screw plug (16) . . . . . . . . . . . . . . . . . . . . . . . . unscrew, screw on, special tool103 589 01 09 00. Tightening torque 30 Nm.

NoteScrew plug is pressurized by compressionspring. Replace seal (17).

Oil overpressure valve (14) . . . . . , . . . . . . . . , . remove, insert.

NoteCheck that oil overpressure valve is in propercondition and moves easily in timing case cover,clean bore if necessary and replace oiloverpressure valve.

With engine running . . . . . . . . . . , . . . . . . . . . . check for leaks.

18.09-2151

Special tools

001 589 72 21 00 103 58901 0900

NoteThe oil overpressure valve is installed at the side(on the left looking in direction of travel) in thetiming case cover and connects pressurechamber (A), and suction chamber (B) of the oil

pump.

14 P1storl15 Compression spring16 Screw plug17 Seal

A Pressure chamberB Suction chamber

l l a3-

P18-0033-35A

18.09.215i2

From an oil overpressure of approx. 4 bar, thepiston (14) is pushed against the force of thecompression spring (15) and opens the reliefcross-section along which part of the oil flowsback to the suction chamber (B), depending onpressure.

When the piston (14) is moved, the oil which ison the rear of the piston in chamber (C) isdisplaced and flows through the relief grooves onthe outside of piston likewise to the suctionchamber (B).

l&09-215/3

18-220 Checking oil level indicator

Model 201

Al

’ O.Sbr/vs -0

;;iX5/2

- 0,5br/ws 1

B5 S42

- I - - -.75br/gn

Wiring diagram engine oil level indicator, engine coolant level indicator, windshield washer levelindicator

Al Instrument clusterel Left turn-signal indicatore2 Right turn-signal indicatore3 High beam indicator64 Fuel reserve warning lampe5 Battery charge Indicatore6 Brake pad wear indicator lamp87 Brake fluid and parking brake indicator lampe6 Instrument lightrng811 Engrne coolant level indicator lampe12 Oil level Indicator lampel3 Windscreen washer indicator lamp

PtP2P9P7

B5S41542S43W1X5/2

Engine coolant temperature gaugeFuel gaugeOil pressure gaugeElectronrc clock/tachometer011 pressure gauge sensorEngine coolant level Indicator lamp swatchWindsshield washer level indicator lamp swatch011 level Indicator lamp swatchMain ground (behind instrument cluster)Connector, Intenor/starter 4-pin

18.09-220/l

Test data

Resistance at max. oil level

Resistance at min. oil level

Battery voltage approx. 12 V

Commercial tool

Multimeter e.g. Sun, DMM-5

NoteIf problems occur as for example:

A. Indicator lights up constantly whenengine running and oil at correct level.

B. Indicator lamp does not light up whenkey in position “2”.

C. Indicator lamp does not light up whenengine running, oil temperature ~60 “Cand oil level below “min”.

Test

A. Indicator lamp lights up constantlywhen engine running and oil at correctlevel.

Test oil level sensor. Detach connector. Testconnector to ground with multimeter.

Reading: < 1 s1

Yes No

Replace oil level sensor.

L

I I

If

18.09-22Ot2

Test cable. Remove instrument cluster for thispurpose. Test resistance with ohmmeterbetween contact 5 of 15pin connector andcontact of oil level sensor.

Reading: < 1 Q

Yes I No

Replace indicating instrument.

B. Indicator lamp does not light up whenkey in position “2” (check function).

Check operation of bulb.

Yes NoI I

f

Remove instrument cluster. Measure voltagewith multimeter at contacts 6 and 9 of the 15-pin connector.

Reading: approx. 12 V

Yes No

Replace indicating instrument.

Modul 102 Format 1 ,O (77x58 mm)

Bild-Motiv

FoWZg-Nr.

Abgabe

Korrektur

Bild-Nr. P18-0076-13

P20-0076-13

C. Indicator lamp does not light up whenengine running, oil temperature ~60 “Cand oil level below “min”, checkfunction section “B” in order.

I 1Test oil level sensor. Detach connector for thispurpose. Test connector to ground withmultimeter.

Reading: 00 Q I

Yes No

+

Replace indicating instrument.

I End of test I

18.09-22014

18-225 Function of low engine oil level indicator

1 instrument cluster5 lgnhon lock351 Oil level sensor

a Electronicsb 8A fuse

ComponentsOil level sensor in oil sump (351).

Indicator lamp in instrument cluster. Symbol:dripping oil can (1).

Electronics at instrument cluster (a).

GeneralThe dynamic low engine oil level indicatormonitors the oil level in the sump when theengine is running and at an oil temperatureabove 60 “C.

No indication is given below 60 “C.

The low engine oil level indicator lights up whenthe ignition is switched on (check function) andgoes out as soon as the engine is running.

The low engine oil level indicator shows a weaklight for the check function and a bright light inthe event of a fault.

18.09-22511

The oil level in the sump is detected by a float(358) with permanent magnet (359) installed inthe oil level sensor. Within the minimum range ofthe dipstick, the float opens the Reed contact(360) and a signal from the electronics in theinstrument cluster is interrupted. The indicatorlamp lights up.

27351352356359360365a

b Dscharge passage 4 mm dia.

011 sumpOil level sensor&metal snap diskFloatPermanent magnetReed contact0-nngAir admIssIon passage 8 mmdia.

The same also occurs in the event of a cableinterruption.

When the oil level drops, the indicator lamplights up first of all briefly and later shows asteady light, depending on the driving style.

To avoid unnecessary warnings in various drivingsituations, e.g. a sharp lefthand curve, theelectronics is equipped with a delay circuit. Itprevents the indicator lamp from lighting up untilan oil shortage has been signaled for 60seconds.

360361352

To avoid incorrect indications when the engine iscold (viscous oil flows back only slowly to thesump), the oil level sensor is equipped with abimetal snap disk (352). This prevents the floatchamber above the discharge passage (b)running empty at low temperatures.

18.09-22512

Switching points of bimetal snap disk

Opens at approx. 60 “C oil temperature.

Closes at approx. 30 “C oil temperature.

When changing the oil, the float chamber abovethe air admission passage (1) is filled with oil.Any subsequent faulty indications are thus notpossible.

The oil level indicator is designed so that theindicator lamp lights up just before the “min”marking on the dipstick (safety margin).

Maintenance and repair instructionsThe oil level indicator does not eliminate theneed for checking the oil level with the dipstickwhen changing the oil.

The oil level sensor (351) can be removed whenthe oil sump is installed. Drain approx. 2 liters ofengine oil for this purpose.

l&09-225/3