Steering System Maintenance Guidelines · PDF filePoppet Resetting Single Gear ... seal is...

TRW AutomotiveCommercial Steering Systems

Steering System Maintenance Guidelines

Hazard Warning Definitions

A warning describes hazards or unsafe practices which could result in severe personal injury or death.

Throughout this troubleshooting guide, test procedures are recommended to help locate the cause of each complaint. While performing these tests,

TRW advises that you TAKE NECESSARY PRECAUTIONS when working with internal vehicle components and hot hydraulic fluids.

A caution describes hazards or unsafe practices which could result in personal injury or product or property damage.

A note gives key information to make following a procedure easier or quicker.

Notice

Power Steering System Analyzer (PSSA) Gauge

This guide was prepared for the purpose of providing general advice concerning the diagnosis and correction of commercial vehicle steering related problems. This guide is intended for the use of properly trained, professional mechanics, NOT “Do-it-Yourselfers”. Also, this guide should be used in conjunction with service manuals provided by both the vehicle and component manufacturers. Diagnosis and correction of commercial vehicle steering related problems should only be handled by properly trained, professional mechanics who have the proper equipment, tools, instructions and know-how to perform the work properly and safely.

Some of the tests in this manual require the use of a PSSA. This device is a combination flow meter, shut-off valve, and pressure gauge. This tool will allow you to measure flow and pressure, and provide a load on the pump through the hydraulic lines of the steering system. This tool is required to correctly analyze a steering system. TRW recommends that you DO NOT BEGIN TROUBLESHOOTING A STEERING SYSTEM WITHOUT THE USE OF A PSSA. If you are not sure how to use a PSSA, you may refer to the video available through our website at: www.trucksteering.com. This video compliments the tests in this book which require the use of the PSSA.

© TRW Inc., 2008

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Table of Contents Preventative Maintenance Guidelines ............................................... 5 Approved Fluids and Grease ................................................................. 6 Input Shaft Seal Replacement .............................................................. 7 Seal Removal .................................................................................... 8 Seal Inspection ................................................................................. 9 Sector Shaft Adjustment ...................................................................... 10 Poppets ................................................................................................... 11 Resetting Criteria ........................................................................... 11 System Identification ...................................................................... 12 Initial Poppet Setting Procedure .................................................... 12 Poppet Resetting Single Gear System ........................................... 13 Poppet Resetting Mirror System .................................................... 15 Poppet Resetting Reverse System ................................................. 17 Main Gear Adjustment ................................................................... 18 Rotary Cylinder Adjustment ........................................................... 18 Air Bleeding the Steering System ..................................................... 19 Visual Identification ........................................................................ 19 Auto Bleed Gears ........................................................................... 19 Maual Bleed Gears ......................................................................... 20 Flushing the Steering System ............................................................. 21 Power Steering System Analyzer (PSSA) Application and Use .. 23 Installing the PSSA ......................................................................... 23 Power Steering Pump Test ............................................................. 25 Poppet Trip Pressure Test ............................................................... 26 Test Result Charts .......................................................................... 28 PSSA Installations (Various Gear Configurations) ......................... 29 Linkage Inspection, Maintenance, Replacement, and Adjustment ........................................................... 30 Maintenance Checklist ................................................................... 30 Tie Rod End Replacement ............................................................... 31 Draglink - One End Adjustable ....................................................... 32 Draglink - Two end Adjustable ....................................................... 33 Tie Rod Tube Assembly - One End Adjustable ............................... 34 Tie Rod Tube Assembly - TwoEnd Adjustable ................................ 35 Drop Center Tie Rod Tube Assembly - One End Adjustable ........... 36

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Lubrication guidelines for tie rod and draglink ends.• Highway(Every20,000miles)• Pick-up/Delivery(2x/month)• HeavyDuty(Every500hours)• SevereDuty(Every250hours)Usehandoperatedgreasegun.

Tighten tie rod end pinch clamp bolt to approved OEM torque specification.(4x/year)

Tighten pitman arm connection to approved torque specification.(4x/year)

Check cotter pin at slotted nut on all tie rod and draglink ends. Check nut torque and replace cotter pin, if missing.(At each lube cycle)

Replenish lube under dirt and water seal.(2x/year)

Inspect U-joint and pinch bolts. Torque to approved specification.(4x/year)

If equipped with grease fittings, lube intermediate column U-joints and slip joint.(At each lube cycle)

Drain reservoir and replace filter.(1x/year - Highway, 2x/year - Severe Duty)

Routinely check oil level. See list of approved hydraulic fluid on following page.

Tighten hose clamps and inspect all hydraulic hoses and connections for leakage. Bleed air from the system, if required.(2x/year)

Lubricate at trunnion grease fitting with hand operated gun only.(At each lube cycle)

CAUTION

Neverhighpressurewashorsteamcleanapowersteeringgearwhileonoroffthevehicle.Thiswillforcecontaminantsintothegear,especiallythroughthesidecoverventplughole,inputshaftseal,andoutputshaftsealareas.Thesecontaminantscoulddestroyseals,bushings,andbearings.Resultinginareductionofsteeringgearperformance.

Preventive Maintenance Guidelines

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Approved Hydraulic Fluids

Thetypeoffluidusedinthepowersteeringsystemisvitaltoextendboththelifeofthecomponentsanditsseals.ItisnecessarytoutilizeasteeringsystemfluidthatisspecifiedandapprovedbythevehiclemanufacturerandalsocomplieswithTRWCommercialSteeringSystems’recommendation.

Itisrecommendedthatanyfluidspecification,outsideofthecompliantlubricantlisted,bereviewedbyTRWtoensurethecompatibilitybetweenthecomponentandfluidtypebeingused.

TRWrecommendsusingoneofthefollowingfluidsinthepowersteeringsystem.

AutomaticTransmissionFluid •DexronII •DexronIII •FordMercon

NOTE

Thesteeringsystemshouldbekeptfilledwithoneoftheabovefluids.

CAUTION

Completelyflushthesteeringsystemwhenchangingtoanotherfluid.Replacethereservoirfilterafterflushingthesystem.Fillthesystemwithoneoftherecommendedfluidsabove,only.Donotmixfluidtypes.Anymixtureoranyunapprovedoilcouldleadtosealdeteriorationandleaks.Aleakcouldultimatelycausethelossoffluid,whichcouldresultinalossofpowersteeringassist.

Besuretobleedtheairoutofthesystembeforeputtingthevehiclebackintoservice.

Approved Grease

#2NLGIextremepressure,lithiumbased,molyfilled,heavydutygrease.MobilSHC100foruseongreasableintermediatecolumnslipjoint

NOTE

Morespecificproceduresandintervalscanbefoundinthevehiclemanufacturersservicemanual.TheseproceduresareTRW’sgeneralguidelinesforsteeringrelatedpreventivemaintenance.Servicemanualsandtechnicalbulletinsarealsoavailablethroughourwebsite.

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Input Shaft Seal Replacement

Detecting Input Shaft Seal Leakage

TRWpowersteeringgearsincorporatean“Umbrella”styleexternaldirtsealbetweenthesteeringshaftU-jointandthehousingofthesteeringgear.ThecavityunderthissealisfilledbyTRWatassemblywithaspecialgreasetoinhibitcorrosionoftheinputshaftneartheinputshaftseal.Sincethis“Umbrella”doesnotpositivelyinterferewiththemainhousing,someamountofthegreaseunderitcanmigratetotheexternalhousingsurfaces.Overtime,especiallyunderelevatedoperatingtemperatures,someofthebaseoilinthegreasecanseparatefromthecarrier.Thisthinfilmofoilcanspreadovertheupperpartofthegear,attractdustanddirt,causingtheappearancethattheinputshaftsealisleakingpowersteeringfluid.

Initialinspectioncriteriatodetermineiftheinputshaftsealisleaking:• Ifthedust/dirtinthisareais“dry”(notsaturatedornotdrippingfluid)theinputshaftsealisoperatingproperly.

• Ifithasnotbeennecessarytoreplenishthereservoirfluidlevelfrequently,theinputshaftsealisoperatingproperly.

• Ifthedust/dirtis“Wet”orappearsas“cakedmud”thenacloserlookisrequired.

Additionally,thefollowingareothercausesthatmaypresentfalseindicationsofinputshaftsealleakage.• Lookforsignsofover-greasingtheU-jointyoke(whichcanspreadtotheinputshaftsealofthesteeringgearovertime,

creatinganappearanceofleakage),leakingpowersteeringhoses(theyareusuallycoveredwitha“wetmud”whentherubberpartstartstofail).

• Oilleakscanoccuratthehosefittingswhichgiveafalseindicationofasteeringgearinputshaftsealleak.

• Onmanyvehicles,thereservoirislocateddirectlyoverthesteeringgear.Overfilledorleakingreservoirscandripontothesteeringgearresultinginafalseindicationofaninputshaftsealleak.

Inordertodetermineiftheinputshaftsealisleaking,dothefollowing:1. Wipedowntheareaofthesteeringgeararoundtheinputshaftsealandhoseconnections.

CAUTION

Neverhighpressurewashorsteamcleanapowersteeringgearwhileonoroffthevehicle.Thiswillforcecontaminantsintothegear,especiallythroughthesidecoverventplughole,inputshaftseal,andoutputshaftsealareas.Thesecontaminantscoulddestroyseals,bushings,andbearings.Resultinginareductionofsteeringgearperformance.

2. Withthevehicleparkedandatemperaturegaugeinsertedinthereservoir,observetheinputshaftsealareaandhoseconnectionswhilerunningtheengineandsteeringthevehiclefor5-10minutes.Theoiltemperatureshouldbe130°-160°Fwhenobservingsealareaandhoseconnections.

CAUTION Donotletoiltemperatureexceed250°Fwhileperformingthismaneuver.

Conclusions:• Iffluidleakageisnotedfromthereservoir,hose,fittings,orotherplumbingconnections,repairtheproblemandretest.

• Ifnofluidleakageisobserved,thentheappearanceofleakageislikelyamigrationofgreasenotasealfailure.

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Seal Removal Thisprocedureusesthevehicle’spowersteeringpumptoforceouttheinputshaftseal.Tousethisprocedure,thepowersteeringpumpshouldhaveaminimumof1,500psiavailable.1. Placeadrippanonthefloortocatchtheoil.

2. Disconnectreturnline(Figure1)fromthesteeringgear.Plugthereturnlineandcapthereturnportofthegearwithhighpressurefittings

3. Disconnecttheintermediatecolumnfromthesteeringgear’sinputshaft.Cleantheinputshaftendofthesteeringgear.

4. Removethedirtandwatersealfromthesteeringgear.

5. Wipeoutthegreasefrombehindthedirtandwaterseal.

6. Insertasmallscrewdriverintothenotchformedintheendofthespiralretainingring(Figure2).Removetheretainingring.Becarefulnottoscratchtheborewiththescrewdriver.

7. Sliptheintermediatecolumnbackontotheinputshaftwiththepinchboltinstalled,butnottightened.

8. Tieacleanshoptowel(Figure3)aroundtheinputshaftareatoreduceoilspatter.

9. Checkthereservoir,andaddfluidifnecessary,untilthelevelisatthe“full”markonthedipstick.Donotmixfluidtypes.

CAUTION

Anymixtureoffluidtypes,oruseofanyunapprovedfluidcouldleadtosealdeteriorationandleaks.Aleakcouldultimatelycausethelossoffluid,whichcouldresultinalossofpowersteeringassist.

10. Withthevehicleinneutral,momentarilyturnthestarter(quicklyturnofftheengineifitstarts).

11. Removetheshoptowel.Disconnecttheintermediatecolumn(Figure4),andremovetheinputshaftseal(Figure5).

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

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Seal Inspection

1. Checkthesealareaofthevalvehousingforanysealfragments.Removealldebris.

2. Checkthesealforheatdamage.Ifthesealisstiffandbrittle,andnotpli-ablelikethenewseal(Figure6),itisprobablyheatdamaged.Determineandfixthecauseofexcessiveheatinthesteeringsystem.

Seal Installation

1. Putcleangrease(providedinthekit)ontheinsidediameterofthenewinputshaftseal,andplaceitovertheinputshaft.

2. Placesmalldiameter-endofthesealinstallertool(J37073)overtheinputshaftandagainsttheseal(Figure7).Tapthesealinstallertooluntilthetoolshoulderissquareagainstthevalvehousing.Removeanysealmate-rialthatmayhaveshearedoffinthesealboreorretainingringgroove.

CAUTION Donotuseasockettoinstallthissealbecauseyouwillnotbeabletocontrolsealinstallationdepth,possiblycausingaleak.

3. Insertnewretainingringintothegroove(Figure8).

4. Packtheendofthevalvehousingborearoundtheinputshaftwithgrease(providedinthekit).Choosethecorrectsizeofthenewdirt&watersealbycomparingittotheoldseal,orbymeasuringthemajordiameteroftheinputshaftserrations(seechartbelow).Applymoregreasetotheback-sideofthenewdirt&watersealandinstallitovertheinputshaft(Figure9).Seatitinthegroovebehindtheserrationsandagainstthevalvehous-ing.

SealPartNumber SerrationSize MajorSerrationDiameter 478044 13/16”x36 0.807/0.799 478060 7/8x36 0.866/0.857 478050 1”x36 0.987/0.977 478050 1”x79 1.008/1.000

5. Reconnecttheintermediatecolumn(Figure10)totheinputshaftandtightenthepinchbolttotorquelevelspecifiedbythevehiclemanufacturer.

6. Reconnectthereturnlinetothesteeringgearreturnport.Then,refillthereservoirifnecessary.

7. AirbleedthesystemusingtheprocedureoutlinedbyTRW.

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

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Sector Shaft Adjustment

Thesectorshaftadjustmentprocedurecanonlybecompletedonthevehicleiftheadjustingscrewandjamnutareaccessible.Thisnutislocatedonthesidecover.

1. Withtheengineon,rotatethesteeringwheeluntilthewheelsarestraightaheadandthetimingmarkonthesectorshaft(Figure1)linesupwiththemarkonthehousing.Thelineonthesectorshaftshouldbeata90°anglefromtheinputshaft.Thesectorshaftisnowcenteredandpreparedfortheadjustment.

2. Turnthevehicleoff.

3. Removethedraglinkfromthepitmanarm.

4. Toavoidresettingthepoppets,donotrotatetheinputshaftmorethan11⁄2turnsfromthe“centered”positionwhilethedraglinkisdisconnected.

5. Whileinthe“centered”position,graspthepitmanarm(Figure2)andgentlytrytorotateitbackandforth.Ifloosenessorlashisfeltatthispoint,thesectorshaftisoutofadjustment.

6. Loosenthejamnut.

7. IfnolashwasdetectedinStep4,turntheshaftadjustingscrew(Figure3)counterclockwiseuntilyoufeellashattheoutputshaft.

8. Slowlyturnthesectorshaftadjustingscrewclockwiseuntilyoufeelnolashusingonlyslightpressureonthepitmanarm,about10ft•lboftorque.

9. Holdtheadjustingscrewinplace,andtightenthejamnut.Torquethejamnutto43ft•lb(58N•m).

10. Turnthesteeringwheel1⁄4turneachsideofcenter,thenbacktocenterandrecheckthepitmanarmforlash.Ifyoustillfeellash,repeattheprocedure.

11. Reconnectthedraglinktothepitmanarm.Torquethenuttoapprovedvehiclemanufacturer’sspecificationsandreinsertcotterpin.

12. Maintaingreaseinthesectorshaftbearingthroughthegreasefitting(Figure4)inthehousingusingonlyahandoperatedgreasegun.Addgreaseuntilitbeginstopurgepastthedirtandwaterseal.

CAUTION

Donotuseapowergreasegunbecauseitwillsupplygreasetoofast;thiscouldadverselyaffectthehighpressuresealandcontaminatethehydraulicfluid.

Figure 1

Figure 2

Figure 3

Figure 4

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Poppets

What are Poppets?

Poppetsarepressureunloadingvalves,insidetherackpiston,that“relieve”just beforeafullturnismadeineachdirection.Whenpoppetsaresetorresetcorrectly,systempressurewillbereducedbeforetheaxlestopboltcontactstheaxlestopinbothdirections.

Poppet Resetting Criteria

PoppetsonTRWsteeringgearsdonothavetobereset,unlessthevehiclehasbeenmodifiedinsuchawaythatwheelcutforthevehicleisdecreased.

Ifthegearhasafixedstopboltandyouaredecreasingthevehicle’swheelcut,youwillneedanewpoppetadjustingscrewandjamnut.Ifwheelcutisbeingincreased,thepoppetswillresetautomatically.Inthiscase,refertothePoppetSettingprocedure.

Examplesofmodificationsthatrequirepoppetresettinginclude:

•Changingtolargertires •Reducingwheelcutforanyreason •SteeraxleU-boltswerebentorbroken •Ifthepitmanarmwasmistimedandwasretimed •Axlestopboltsweredamagedandhavebeenreplaced •Orwhenthesteeringgearhasbeenmountedonadifferentvehicle.

NOTE

UsethePOPPETRESETTINGPROCEDURESonlyifyoumadeamodificationtothevehicleasoutlinedinthelistabove.

Steering Gear - Section View

1. FixedStopBolt2. LowerPoppet3. LowerPoppetSeat4. LowerPoppetSleeve5. Spring6. PushTube7. UpperPoppetSleeve8. UpperPoppetSeat9. UpperPoppet10. ValveHousing11. InputShaft12. Valve13. RecirculatingSteelBalls14. RackPiston15. WormScrew16. PitmanArm17. TimingMarks18. SectorShaft19. Housing

1 32 4 5 6 7 8 9 10

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111215

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18

17

16

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System Identification

Beforeresettingpoppetsonasteeringgear,youmustidentifythetypeofsystemwithwhichyouareworking.

Forsinglegearandagearwithlinearassistcylinders,usetheSingleGearPoppetResettingprocedure.

Onadualgearsystem,youmustdeterminewhetherthesystemhaseithermirrorimagegearsorreversedimagegears.Theproceduresareslightlydifferentforeachtypeofsystem,sousethefollowingcriteriatoidentifywhichmethodappliestoyourapplication.

1. Parkthevehiclewiththewheelsturnedallthewaytotheaxlestopineitherdirection.Turnthevehicleoff.

2. Lookattheoutputshafttimingmarknearestthehousingpistonboreonthemaingear.Isthismarkpointingtowardthepoppetscreworawayfromit?

3. Nowchecktheoutputshafttimingmarknearestthehousingpistonboreontherotarycylinder.Doesitpointtowardthepoppetscreworawayfromit?

UsetheMIRRORSYSTEMprocedureifthetimingmarkspointtooppositeendsofthegears.

UsetheREVERSESYSTEMprocedureifbothtimingmarkspointtowardthepoppetscrewsorbothpointtowardtheendoppositethepoppetscrews.

Initial Poppet Setting Procedure

Forthisproceduretoworkcorrectly,youmusthave1)AneworremanufacturedgearreceivedfromTRWoryourvehiclemanufacturer’saftermarketsystem,or2)ausedgearonwhichpoppetseatshavebeenreplacedorresetduringgeardisassemblyandassemblyprocedures.Also,afixedstopboltorapoppetadjustingscrewmustbepartofthesteeringgearassembly.

Tosetthepoppetsonaneworremanufacturedsteeringgear,followthesesimplesteps.

1. Makesuretheaxlestopboltsaresettovehiclemanufacturer’swheelcutorclearancespecifications.

2. Raisethefrontendsothesteeraxletiresareofftheground.

3. Starttheengineandletitidle.

4. Steerthevehicleininonedirection,untilyoucontacttheaxlestop.Pullhardonthesteeringwheel.

5. Now,steerthevehicleintheoppositedirectionuntilyoucontacttheaxlestop.Again,pullhardonthesteeringwheel.

6. Turnthevehicleoff.

Rotary Cylinder Main Gear

Poppet Screws

Rotary Cylinder Main Gear

Poppet Screws

Reverse System

Mirror System

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Single Gear Poppet Resetting Procedure

1. Settheaxlestopstovehiclemanufacturer’swheelcutorclearancespecifications.

2. Makesuretheengineisoffandtheroadwheelsareinthestraightaheadposition.

3. Removeanddiscardthepoppetfixedstopboltandwasher(Figure1,ifequipped)fromthelowerendofthehousing.Ifthegearhasapoppetadjustingscrewandjamnutthatneedtobereplaced,removeanddiscardthematthispointalso.

4. Ifanewpoppetadjustingscrewandnutarebeingused,turnthescrewintothenon-sealingendofthejamnutuntiltheAllendriveendofthescrewisflushwiththenut(Figure2).

CAUTION

BesuretheAllendriveendofthescrewisnotbelowthefaceofthenut.Failingtokeepitflushwiththefaceofthenutwillcausethepoppetseatflangetobreaklateronduringthisprocedure.

5. Iftheadjustingscrewisalreadypartofthesteeringgear(Figure3),backthenutoffoftheadjustingscrewuntilitisflushwiththeAllendriveendoftheadjustingscrew.

6. TurnthenewadjustingscrewandjamnutintothehousinguntilthenutisfirmlyagainstthehousingusinganAllenwrench.Tightenthejamnutagainstthehousing.

7. Refillthesystemreservoirwithapprovedhydraulicfluid.

CAUTION

Donotmixfluidtypes.Mixingoftransmissionfluid,motoroil,orotherhydraulicfluidswillcausesealstodeterioratefaster.

8. Placeajackunderthecenterofthefrontaxleandraisethefrontendofthevehiclesothesteeraxletiresareofftheground.

9. Starttheengineandletitrunatidlespeed.

10. Notewhichoutputshafttimingmarkisnearestthehousingpistonbore.

11. Turnthesteeringwheelinthedirectionthatmakesthistimingmarkmovetowardtheadjustingscrewyoujustinstalled(Figure4).Turninthisdirectionuntilaxlestopcontactismade.

12. Pullhard(Figure5)onthesteeringwheel(putupto40lbrimpullona20”dia.steeringwheel)aftertheaxlestopiscontacted.

CAUTION

Donotholdthesteeringwheelatfullturnformorethan10secondsatatime;theheatbuild-upatpumpreliefpressuremaydamagesystemcomponents.

Figure 2

Figure 1

Figure 3

Figure 4

Figure 5

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13. Turnthesteeringwheelintheoppositedirection(endoftimingmarkawayfromadjustingscrew,Figure6)untiltheotheraxlestopiscontacted.

14. Pullhardonthesteeringwheel.

15. Releasethesteeringwheelandshutofftheengine.

16. Loosenthejamnutandbackouttheadjustingscrewuntil1”ispastthenut(Figure7).Tightenthejamnutagainstthehousing.


18. Turnthesteeringwheel,sothatthetimingmarkontheoutputshaftpointstowardtheadjustingscrew,untilaxlestopcontactismade.

19. Pullhardonthesteeringwheelandholditinthispositionfornomorethan10secondsatatime,thenreleasetoallowthesystemtocool.

20. Repeatthisholdandreleaseprocesswhilecompletingsteps21-22.

21. Loosenthejamnutandholditinplacewithawrenchsoitwillnotcontactthehousing.

22. Withsteeringwheelheldatfullturn,turntheadjustingscrewin(clockwise)usingfinger-pressureonly(donotusearatchet),untiltheAllenwrenchstops(Figure8).Atthispoint,theadjustingscrewhascontactedthepop-petseat.Donotattempttoturnitinfarther.

NOTE

Pausetheturning-inprocesseachtimethedriverreleasesthesteeringwheel;continueturningtheadjustingscrewinonlywhilethewheelisheldatfullturn.

23. Backofftheadjustingscrew31/4turnsandtightenthejamnut.Torquethejamnutto35ft•lbs.

Thepoppetshavenowbeenreset.Lowerthevehicleandremovethejack.

Besuretocheckthereservoirandfillifrequired.

NOTE

Donotremovetheadjustingscrew,itisnowpartofthesteeringgearassembly.

NOTE

Thelengthofthepoppetadjustingscrewbeyondthenutmaybedifferentforeachvehicle,butmustbenomorethan11/16”forproperthreadengagement(Figure9).

Figure 7

Figure 6

Figure 9

Figure 8

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Poppet Resetting - Mirror System

Thisresettingprocedurewillworkinmostcaseswithatleast13/4hand-wheel-turnsfromeachsideofcenter.Ifyou’remakingalargereductioninwheelcutandthisproceduredoesnotwork,youmayhavetoreplaceorinternallyresetthepoppetsusingtheproceduredescribedintheappropriategearservicemanual.


2. Makesuretheengineisoffandtheroadwheelsareinstraightaheadposition.

3. Removeanddiscardthepoppetfixedstopboltandwasher(ifequipped)fromthelowerendofthehousingonboththemaingearandtherotarycylinder.Ifeitherunithasapoppetadjustingscrewandjamnutthatneedtobereplaced,removeanddiscardthematthispointalso.

Ifanewpoppetadjustingscrewandnutarebeingused,turnthescrewsintothenon-sealingendofthejamnutsuntiltheAllendriveendofthescrewisflushwiththenut.

CAUTION


4. Iftheadjustingscrewisalreadypartofthemaingearorrotarycylinder,backthenutoffoftheadjustingscrewuntilitisflushwiththeAllendriveendoftheadjustingscrew.

5. Turnthenewadjustingscrewandjamnut(withoutrotatingthejamnutonthescrew)intothehousinguntilthejamnutisfirmlyagainstthehousing,onboththemaingearandtherotarycylinder,usinganAllenwrench.Tightenthejamnutagainstthehousing.


CAUTION





10. Turnthesteeringwheelinthedirectionthatmakesthistimingmarkmovetowardtheadjustingscrewyoujustinstalledonthemaingear.Turninthisdirectionuntilaxlestopcontactismade.

11. Pullhardonthesteeringwheel(put40lbs.rimpullona20”dia.steeringwheel)aftertheaxlestopiscontacted.

CAUTION


12. Turnthesteeringwheelintheoppositedirection(endoftimingmarkpointsawayfromadjustingscrewonthemaingear)untiltheotheraxlestopiscontacted.


15


15. Loosenthejamnutandbackouttheadjustingscrew,onboththemaingearandtherotarycylinder,until1”ispastthenut.Tightenthejamnutsagainstthehousings.


17. Turnthesteeringwheel,sothatthetimingmarkonthemaingearoutputshaftpointstowardtheadjustingscrew,untilaxlestopcontactismade.


19. Repeatthisholdandreleaseprocesswhilecompletingthefollowingstepsforboththemaingearandrotarycylinderadjustments.

NOTE


Main Gear Adjustment 1. Withsteeringwheelheldatfullturn,loosenthejamnutonthemaingear,andholditinplacewithawrenchsoitwillnot

contactthehousing.

2. Turntheadjustingscrewin(clockwise)usingfinger-pressureonly(donotusearatchet),untiltheAllenwrenchstops.Atthispoint,theadjustingscrewhascontactedthepoppetseat.Donotattempttoturnitinfarther.


Rotary Cylinder Adjustment 1. Turnthesteeringwheelintheoppositedirection,sothatthetimingmarkonthemaingearoutputshaftpointsawayfrom

theadjustingscrew,untilaxlestopcontactismade.

2. Withsteeringwheelheldatfullturn,loosenthejamnutontherotarycylinderandholditinplacewithawrenchsoitwillnotcontactthehousing.



5. Thepoppetsonboththemaingearandrotarycylinderhavenowbeenreset.Lowerthevehicle.Checkthefluidlevelinthereservoirandfillifrequired.

NOTE

Donotremovethepoppetadjustingscrews,theyarenowpartofthemaingearandrotarycylinderassemblies.NOTE

Thelengthofthepoppetadjustingscrewbeyondthenutmaybedifferentforeachvehicle,butmustbenomorethan11/16”forproperthreadengagement.

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Poppet Resetting - Reverse System

Thisresettingprocedurewillworkinmostcaseswithatleast13/4hand-wheel-turnsfromeachsideofcenter.Ifyou’remakingalargereductioninwheelcutandthisproceduredoesnotwork,youmayhavetoreplaceorinternallyresetthepoppetsusingtheproceduredescribedintheappropriategearservicemanual.


2. Makesuretheengineisoffandtheroadwheelsareinstraightaheadposition.

3. Removeanddiscardthepoppetfixedstopboltandwasher(ifequipped)fromthelowerendofthehousingonboththemaingearandtherotarycylinder.Ifeitherunithasapoppetadjustingscrewandjamnutthatneedtobereplaced,removeanddiscardthematthispointalso.Ifanewpoppetadjustingscrewandnutarebeingused,turnthescrewsintothenon-sealingendofthejamnutsuntiltheAllendriveendofthescrewisflushwiththenut.

CAUTION


4. Iftheadjustingscrewisalreadypartofthemaingearorrotarycylinder,backthenutoffoftheadjustingscrewuntilitisflushwiththeAllendriveendoftheadjustingscrew.

5. Turnthenewadjustingscrewandjamnut(withoutrotatingthejamnutonthescrew)intothehousinguntilthejamnutisfirmlyagainstthehousing,onboththemaingearandtherotarycylinder,usinganAllenwrench.Tightenthejamnutagainstthehousing.


CAUTION





10. Turnthesteeringwheelinthedirectionthatmakesthistimingmarkmovetowardtheadjustingscrewsyoujustinstalledonboththemaingearandtherotarycylinder.Turninthisdirectionuntilaxlestopcontactismade.

11. Pullhardonthesteeringwheel(put40lbs.rimpullona20”dia.steeringwheel)aftertheaxlestopiscontacted.

CAUTION


12. Turnthesteeringwheelintheoppositedirection(endoftimingmarkpointsawayfromadjustingscrew)untiltheotheraxlestopiscontacted.


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15. Loosenthejamnutandbackouttheadjustingscrewuntil1”ispastthenutonboththemaingearandtherotarycylinder.Tightenthejamnutagainstbothhousings.


17. Turnthesteeringwheel,sothatthetimingmarkontheoutputshaftpointstowardtheadjustingscrew,untilaxlestopcontactismade.


19. Repeatthisholdandreleaseprocesswhilecompletingthefollowingsteps.Firstonthemaingear,thenontherotarycylinder.

NOTE


Main Gear Adjustment 1. Withsteeringwheelheldatfullturn,loosenthejamnutonthemaingear,andholditinplacewithawrenchsoitwillnot

contactthehousing.



Rotary Cylinder Adjustment 1. Withsteeringwheelheldatfullturn,loosenthejamnutontherotarycylinderandholditinplacewithawrenchsoitwill

notcontactthehousing.



4. Thepoppetsonboththemaingearandrotarycylinderhavenowbeenreset.Lowerthevehicle.Checkthefluidlevelinthereservoirandfillifrequired.

NOTE

Donotremovethepoppetadjustingscrews,theyarenowpartofthemaingearandrotarycylinderassemblies.NOTE

Thelengthofthepoppetadjustingscrewbeyondthenutmaybedifferentforeachvehicle,butmustbenomorethan11/16”forproperthreadengagement.

18

Air Bleeding the Steering System

Automatic Bleed Gears

1. Fillthereservoir.

2. Starttheengine,letitrunfor10seconds-withoutsteering,thenshutitoff.

3. Checkthereservoir,andrefillifthefluidlevelhasdropped.

4. Repeatatleastthreetimes,checkingandrefillingthereservoireachtimeifnecessary.

NOTE

Donotallowthefluidleveltodropsignificantlyorrunoutofthereservoir.Thismayinduceairintothesystem.

5. Starttheengineandletitidlefor2minutes-withoutsteering.Shutofftheengineandcheckthefluidlevelinthereservoir.Refillifrequired.

6. Starttheengineagain.Steerthevehiclefromfulllefttofullrightseveraltimes.Automaticbleedsystemsshouldnowbefreefromtrappedair.

7. Finally,besuretocheckthefluidlevelinthereservoir.Refillifnecessarybeforereturningthevehicletoservice.

Gear Mounting Configurations

Visual Identification

Whenyouairbleedasteeringsystem,youaresimplyallowingairtrappedinthecavitiesofthesteeringgeartoescape.Asageneralrule,ifyoursteeringgearisa“standardmount”,youshouldusetheAutomaticBleedmethod.Ifyourgearisan“invertedmount”,youwillneedtousetheManualBleedmethodtopurgethetrappedairfromthegear.

Auto Bleed Plug Location

Standard Inverted

Auto Bleed Plug Styles

Hex Head Torx Head

19

Manual Bleed Gears

1. Fillthereservoir.

2. Starttheengine,letitrunfor10seconds-withoutsteering,thenshutitoff.

3. Checkthereservoir,andrefillifthefluidlevelhasdropped.

4. Repeatthisprocessatleastthreetimes,checkingandrefillingthereser-voireachtimeifnecessary.

NOTE

Donotallowthefluidleveltodropsignificantlyorrunoutofthereservoir.Thismayinduceairintothesystem.

5. Starttheengineandletitidlefor2minutes-withoutsteering.Shutofftheengineandcheckthefluidlevelinthereservoir.Refillifrequired.

6. Starttheengineagain.Steerthevehiclefromfulllefttofullrightseveraltimes.

7. Again,checkthefluidlevelinthereservoir.

8. Withtheengineidling,steerfromfullleftturntofullrightturnseveraltimes.Stopsteeringwiththewheelspointedstraightaheadandloosenthemanualbleedscrew2-3turns.

9. Allowairandaeratedfluidto“bleedout”untilfluidappearswithoutbubbles.

10. Closethebleedscrew,refillthereservoirifrequired.

11. Repeatthisprocessthreeorfourtimesuntilalltheairisdischarged.Torquemanualbleedscrewto45in•lb.

CAUTION

Donotturnsteeringwheelwithbleedscrewloosened.

Figure 1

Manual Bleed Screw Location

Figure 1

Manual Bleed Screw Style

5/16” Hexagon Screw

20

Flushing the Steering System

Thesteeringsystemmustbeflushedeverytimeagear,pump,orreservoirgetsreplaced,regardlessifthecomponentsareneworareremanufactured.

1. Setparkingbrakeonvehicleandblockrearwheels.

2. Raisethefrontendofftheground.

3. Takevehicleoutofgearandputintoneutralposition.

4. Raisehoodandwipedownareaaroundthesteeringgearandthehydrauliclinesrelatedtothesteeringsystem.

5. Placeadrippanunderthesteeringgeartocatchtheoil.

6. Removeboththepressureandreturnlines(Figure1)fromthesteeringgearandallowtheoiltodrainintotheemptycontainer.

7. Removefilter(Figure2)fromthepowersteeringfluidreservoiranddiscard.Disconnectthesupplylinefromthereservoir.

8. Rinseandcleantheinsideofthereservoirwithanapprovedsolvent,thenairdry.Donotuseashopragtowipetheinsideofthereservoirandmakesurethatnoneofthesolvententerstherestofthesteeringsystem.Ifthereservoirismadefromplasticinspectforcracksanddamage.Replaceifnecessary.

9. Turnsteeringwheelfromfulllefttofullright3-4times.CollectthedrainedoilinthesamecontainerasinStep6.Thiswillpurgetheoilfromthesteeringgear.

10. Reconnectpressureandreturnlinestothesteeringgear.Connectthesupplylinetothereservoirandthentightenallfittings.

11. Installnewfilterelementintothereservoir.

12. Cleanreservoirfillercapwithanapprovedsolvent.Inspectgasketandreplaceifnecessary.

13. Inspectallhydraulichoses(Figure3)forcracks,softorsweatspotsandsignsoflocalcollapse(removeallcovers/corrugatedtubingfromhosestodothis)andreplaceanythatarefoundtobedefective.

14. Checkanyfittingsandconnectorsforblockage.Clearanyblockagesusinganappropriatemethod.

Figure 1

Figure 2

Figure 3

21

15. Fillreservoirwithapprovedreplacementfluidandreinstallthefillercap(Figure5).

16. Startenginefor10seconds,stop,andcheckreservoirfluidlevelandtopoffifnecessary.Youmayneedtorepeatthisprocedure3or4times.

17. Uponcompletionoffillingthereservoir,starttheengineandletitidle.Atengineidle,steerfullrightandfullleft(Figure6)onceandreturntostraightahead.Stopengineandcheckpowersteeringreservoirlevelandtopoffifrequired.

CAUTION

Donotholdsteeringwheelatfullturnforlongerthan10secondsasthiswillcausesystemtooverheat.

18. Restartengineandsteerfullturnseachdirection3or4times.

19. Stopengineandrecheckreservoirfluidlevelandadjusttocorrectlevel,ifneeded.

20. Inspectsystemforleaksandcorrectifnecessary.

21. Bleedairfromthesystem,ifrequired.

22. Removedrippanandlowervehicle.Removeblocksfromwheelsandreturnvehiclefornormalservice.

Figure 6

Figure 5

22

Power Steering System Analyzer (PSSA)Application and UseIntroductionThisbookletisintendedtogivetheyou,thetechnician,abetterunderstandingofthepowersteeringsystemanalyzer.Primarily,howitworksandhowtoproperlyuseittodiagnosehydraulicpowersteeringrelatedissues.YoushouldalsoknowthattheuseofthepowersteeringsystemanalyzerisrequiredwhencompletingmanyofthediagnostictestsfoundinourChartYourWaytoEasySteering-DiagnosticsServiceManual.ThetestproceduresweredevelopedusingTRWpowersteeringcomponents.However,theoperatingprinciplesofthepowersteeringsystemanalyzercanbeappliedtoallcommercialpowersteeringsystems.

Thegoalofthisbookletistotakeyoustep-by-stepthroughteachofthetestprocedureswhichrequiretheuseofthepowersteeringsystemanalyzer.ThiswillthenassistyouinlocatingtherootcauseofanyhydraulicsteeringrelatedcomplaintandprovideyouwithnecessarytestresultswhencallingTRW.

WARNING

Whileperformingthesetests,TRWadvisesthatyoutakenecessaryprecautionswhenworkingwithinternalvehiclecomponentsandhothydraulicfluid.Besuretotakespecialcaretoprotectyourself,andthosearoundyou,whileperformingadiagnostictest.

CAUTION

Donotattempttodiagnoseahydraulicsteeringrelatedproblemwithoutusingapowersteeringsystemanalyzer.Youwillnotbeabletoproperlydeterminethecorrectinformationneededtoanalyzeanddiagnosethesteeringsystem.

Thisbookletwillshowyouhowtoproperlyinstallthepowersteeringsystemanalyzerintothepowersteeringsystemanduseittogetmeasuredresultsforthefollowingtests;PowerSteeringPump,PumpFlowControlResponse,PoppetTripPressure,andInternalLeakage.

Besuretorecordyourresultsinthetables(Page6)andbepreparedtoprovidethisinformationwhencallingtotalkwithyourTRWTechnicalServiceRepresentatives.

Installing the Power Steering System Analyzer

SomeChartYourWaydiagnostictestproceduresrequireapowersteeringsystemanalyzerwhichisacombinationflowmeter,pressuregaugeandloadvalveallinone.Thesystemanalyzerletsyoumeasureflowandpressureandapplyaloadtothepumpthroughthesteeringsystemshydrauliclines.Dependingonthemodelofgaugebeingused,youmayseeanarrowshowingthedirectionoftheoilflow.Thiswillassistyouinmakingsuretheflowmeterisproperlyinstalledinthesystem.Aloadvalve,locatednearthegauge,isusedtoeitherrestrictoropentheflowofoiltothesystem.

ThegaugehasaSAE/MetricscaletoreadtheflowofoilineitherGPM(U.S.gallonsperminute)orLPM(litersperminute).ThesystempressureismeasuredineitherPSI(U.S.poundspersquareinch)orkg/cm2(kilogramspercentimetersquared).

Thepowersteeringsystemanalyzerisinstalledbetweenthepowersteeringpumpandthesteeringgear.Connectthevalveendofthepowersteeringsystemanalyzertothesteeringgear’spressureportandtheotherendtothepump’spressureport.

23

Power Steering Pump Test

Thissectionwillinstructyouonhowtomeasurepumpflowandsystempressure.Besuretofollowthelinestomakesurethattheyarehookedupcorrectlybeforeattemptingtoperformanytests.

Verifyengineidlespeedperoriginalequipmentmanufacturersspecifications.

1. Installthepowersteeringsystemanalyzerinthepressurelinewithloadvalvefullyopen.Recheckandadjustthefluidlevel,ifrequired.Installatemperaturegaugeinthereservoirandbeginthetestwiththefluidtemperaturebetween125-135°F(52-57°C).

2. Runtheengineatidle.Measureandrecordtheflowandpressurereadings(TableA).

CAUTION

Whenclosingthepowersteeringsystemanalyzerloadvalve,dososlowlyandkeepaneyeonthepressuregauge.Donotallowthesystemtoexceed3000psior(207bar)forsafetyofpersonnelandtopreventdamagetothevehicle.

CAUTION

Donotkeeptheloadvalveclosedformorethan5secondsatatimebecausedamagetothesystemmayresultfromexcessiveheatbuild-up.

3.Withtheengineatidel,adjusttheloadvalvetoshow1000PSIonthegauge.Measureandrecordtheflowandpressurereadings(TableA).

4. Nowwiththeloadvalvefullyopen,increasetheenginespeedto1500RPM,measureandrecordtheflowandpressurereadings(TableA).

5. Withtheenginespeedat1500RPM,adjusttheloadvalvetoshow1000PSIonthegauge.Measureandrecordtheflowandpressurereadings(TableA).

6. DeterminetherecommendedflowrangeandmaximumallowablesystempressureforthesteeringsystembeingusedbyreferringtoyourOriginalEquipmentManufacturer’sservicemanualforyourapplication.

7. Comparetheminimumandmaximumflows,andthereliefpressureyoumeasured,togearandpumpspecificationsasshowninyourservicemanuals

8. Iftheminimummeasuredpumpflowislessthantheminimumrecommendedflowforthesteeringgearused;thepumpmaynotbeputtingoutenoughflowforanadequatesteeringspeed.Ifthemaximumsystempressureislowerthanthatspecifiedforthepump,itmaynotbedevelopingenoughpressuretosteerthevehicle.Ifeithercaseexists,thepumpmayneedtoberepairedorreplaced.

NOTE

Whenhydraulictestsarecompletedandhosesarereconnected,checkthefluidlevelandbleedtheairfromthehydraulicsystemusingtheproceduresoutlinedintheappropriatesteeringgearservicemanual.

24

Pump Flow Control Response Test

Thissectionwillinstructyouonhowtodetermineproperpumpflowcontrolresponse.Besuretofollowthelinestomakesurethattheyarehookedupcorrectlybeforeattemptingtoperformanytests.

1.Installthepowersteeringsystemanalyzerinthepressurelinewithloadvalvefullyopen.Recheckandadjustthefluidlevel,ifrequired.Installatemperaturegaugeinthereservoirandbeginthetestwiththefluidtemperaturebetween125-135°F(52-57°C).

CAUTION

Ifthesystemtemperaturegoesover250°F(121°C),or150°F(66°C)abovethesurroundingtemperatureatanytimeduringthetest,stopthetest.Thistemperaturelevelisconsideredextremeandsteeringsystemperformanceandlifewillbeseriouslyaffected.Damagetohoses,seals,andothercomponentsmayresultifoperatedatextremetemperature.Ifthesteeringsystemisoperatingabovetherecommendedtemperatures,theheatproblemmaybetherootcauseofthecomplaint.

CAUTION

Whenclosingthepowersteeringsystemanalyzerloadvalve,dososlowlyandkeepaneyeonthepressuregauge.Donotallowthesystemtoexceed3000psior(207bar)forsafetyofpersonnelandtopreventdamagetothevehicle.

CAUTION

Donotkeeptheloadvalveclosedformorethan5secondsatatimebecausedamagetothesystemmayresultfromexcessiveheatbuild-up.

2. Withtheengineatidle,notetheflowrate.Fullyclosetheloadvalveuntiltheflowdropstozero.Quicklyopentheloadvalveobservingtheflowmeter.Theflowratemustinstantlyreturntothereadingyouhavealreadynoted.

3. Withtheloadvalveopenruntheengineto1500RPMandnotetheflowrate.Fullyclosetheloadvalveuntiltheflowdropstozero.Quicklyopentheloadvalveobservingtheflowmeter.Theflowratemustinstantlyreturntothereadingyouhavealreadynoted.

4. Conductthispumpresponsetestthreetimesatidleandthreetimesat1500RPM.Recordyourresults(TableB).Iftheflowratedoesnotreturnimmediately,thepumpismalfunctioning,whichcanresultinamomentarylossofpowerassist.

NOTE


25

Poppet Trip Pressure Test

Thissectionwillinstructyouonhowtoverifypoppettrippressure.Besuretofollowthelinestomakesurethattheyarehookedupcorrectlybeforeattemptingtoperformanytests.


2. Increaseenginespeedto1500RPM.

3. Steerthevehicleintoafullrightturn.Then,recordthepoppettrippressure(TableC)shownonthepowersteeringsystemanalyzerpressuregauge.

4. Now,steerthevehicleintoafullleftturn,andagain,recordthepoppettrippressure(TableC)shownonthepowersteeringsystemanalyzerpressuregauge.

Eachrecordedvalueshouldbeatleast200-400PSIbelowpumprelieftestvaluepreviouslynotedinTableA.Ifyoudonotmeetthiscriteria,poppetsshouldbereset,usingtheprocedureoutlinedintheappropriatesteeringgearmanual.Whencomplete,makesuretorecheckthevehicletomakesureitisoperatingproperly.

NOTE


Internal Leakage Test

Finally,youwillbeinstructedonhowtomeasureinternalleakageforbothasinglegearanddualgearsystem.Besuretofollowthelinestomakesurethattheyarehookedupcorrectlybeforeattemptingperformanytests.

WARNING

Thistestcanbedangerousifnotperformedcorrectly.Keepyourfingersclearoftheaxlestopsandspacerblockduringthistest.Makesurethatthespacerblockcontactstheaxlestopsquarely.Contactthatisnotsquarecouldbreaktheaxlestopsordangerouslythroworejectthespacerblock.


2. Totestthesteeringgearforinternalleakage,youmustfirstpreventoperationofthegear’sinternalunloading(poppet)valvesorreliefvalve(orboth,insomegears).Thiswillallowfullpumpreliefpressuretodevelop.Topreventoperationofthepoppets,placeanunhardenedsteelspacerblock,atleastoneinchthickandlongenoughtokeepyourfingersclear,betweentheaxlestopatonewheel.Ifthesteeringgearisequippedwithareliefvalve,removethereliefvalvecap,o-ring,andtwopiecereliefvalvefromthesteeringgearvalvehousing.Installthereliefvalveplug,specialtoolnumberJ37130,initsplacetopreventoperationofthesteeringgearreliefvalve.

NOTE

Besureyoureinstallthereliefvalveandvalvecapwithnewo-ring,backintothegearafterthistest.

26

CAUTION

Whenrunningthistest,donotholdthesteeringwheelinthefullturnpositionforlongerthan5to10secondsatatimetoavoiddamagingthepump.3. Turnthesteeringwheeluntiltheaxlestopsbottomonthespacerblock.

4. Apply20poundsofforcetotherimofthesteeringwheelduringthistesttobesurethatthesteeringgearcontrolvalveisfullyclosed.Thepressuregaugeshouldnowreadpumpreliefpressure(seeTableA).Recordthesteeringgearinternalleakage(TableD)ontheflowmeter.

5. Repeatthistestfortheoppositedirectionofturn.

6. Ifinternalleakageisgreaterthan1gallonperminute(3.8litersperminute)andthereisnoauxiliaryhydrauliclinearorrotarycylinderinthesystem,repairorreplacethegear.

Iftheinternalleakageisgreaterthan2gallonsperminute(7.6litersperminute),andthereisanauxiliaryhydrauliclinearorhydraulicrotarycylinderinthesystem,controlledbythegear,isolatetheauxiliarycylinderfromthesystembydisconnectingtheauxiliarycylinderhydrauliclinesatthesteeringgearauxiliaryports.Plugthesteeringgearportswithsuitablesteelorhighpressureplugsorcaps.

Intheeventthatarotarycylinderisusedinthesystem,connectthedisconnectedlinestogetherwithasuitableunionfitting.Inthecaseofalinearcylinder,firstplugthedisconnectedlinesandthendisconnectthecylinderfromsteeringlinkage,makingsureitwillclearthesteeredaxle

RepeattheinternalleakagetestandrecordyourresultsinTableD.Iftheinternalleakageislessthan1gallonperminute(3.8litersperminute),repairorreplacetheauxiliarycylinder.Iftheinternalleakageisgreaterthan1gallonperminute(3.8litersperminute),repairorreplacethegear.

NOTE


27

Test Results

Table A

Table B

Table C

Table D

Single Gear System Dual Gear System

GPM or LPM at: Engine (RPM) No Load 1000 PSIIdle1500

Relief Pressure_________PSI/BAR

PSI or BAR

Pump Relief #1 (Idle)



PSI or BAR

Pump Relief #1 (1500 RPM)



PSI or BAR

Full right hand turn

Full left hand turn

GPM or LPM


Full left hand turn

GPM or LPM


Full left hand turn

28

1

2

5

3

6

8

4

7

1

2

5

11

10

9

3

6

8

4

7

1

2

1413

12

5

11

10

9

3

6

8

4

7

1

2

1413

12

5

11

10

9

3

6

8

4

7

PSSA Installations

Typical Steering System Single Gear System

Dual System Single Gear, Linear Cylinder Assist

Dual System Single Gear, Rotary Cylinder

Legend

1. Thermometer 5. SteeringGear 9. LoadValve 13. AuxilliaryLine2. SupplyLine 6. ReturnLine 10.FlowMeter 14.AssistCylinder3. Pump 7. ReservoirFilter 11. PressureGauge LinearorRotary4. PressureLine 8. Reservoir 12. AuxilliaryLine

29

Inspection Criteria

Firstbylightlyrockingthesteeringwheel,observeanyloosenessinthetwomatingtapers,oranymovementofthestudnut.Loosenessineitherplacerequiresfurtherinspection.

Ifeitherofthematingtaperedpartsshowdistortionorwear,bothpartsmustbereplaced.

Second,makesurethewheelsarestraightahead,thetruckengineisturnedoff,andnoforceisbeingexertedonthelinkagebythesteeringgear.Tocheckthesoundnessofthejoint,justuseyourhandtopushandpullthetierodendinandoutinthedirectionoftheballstudaxis(seeillustration).

Forinspectionpurposes,thelinkmustbeheldwithouttwisting,andwithhand-pressureonly(approximately100lbs),measuredwithascaleforinandoutmotionontheballstudaxis.Iftheinandoutmotiononthestud’saxismeasuresover1/8”or3mmwithhandpressureonly,thenthevehicleshouldbetakenoutofservice.

Ifitmoves,butmeasureslessthan1/8”(3mm)itshouldbereplacedatthenearestpracticalservicecenter.Anymovementlessthan1/8”(3mm)isstrictlyamaintenanceissueforthevehicle.

Donotuseawrenchorotherobjecttoobtainmoreleverage.Applyingleveragetoanylinkagecancausemovementregardlessofwhetherornotthelinkageneedstobereplaced.Applyingleveragecanalsodamagethelinkage

Don’tapplysteeringgearpowertothejointtotestforaworntierodend;thatproducesnormalmovement,andthatmovementisnotanindicatorofwear.

Maintenance Checklist

Eachtimethetierodendsarelubricatedyoushouldalsovisuallyinspectfor:

• Cracks,breaksorbendsinthelinkagecomponents.

• Checkforbrokenclampsandgougesontubesfromrubbingparts.

• Checkformissingordamagedgreasefittings.Sometierodendsarenotequippedwithgreasefittingsfromthefactory.Butifoneissupposedtobethereanditisnot,themissingfittingmustbereplaced.

• Checkforanyformoftearingorimpropersealingontheseal.Alsocheckforwearonthesocketthroat.

• Checkalltierodendconnectionsformissingcotterpins.

Linkage Inspection, Maintenance,Replacement, and Adjustment

Inspect for movement alongvertical axis only.

Tie Rod End - Section View

30

Figure 2

Figure 1

Figure 3

Figure 4

Tie Rod End Replacement

Ifthelashisoriginatingfromthetierodend,itwillneedtobereplaced.Ifthelashisinthetaperedstudconnectionbetweenthetierodendanditsmatingpart,boththetierodendandthematingpartmustbereplacedtorecreateaproperfitbetweenthetwo.

1. Loosentheclamporjamnutonthetierodend(Figure1).

2. Disconnectthetierodendfromthematingcomponent.

3. Unscrewthetierodendfromthetube(Figure2).Useapipewrenchifnecessary,beingcarefulnottodeformthetube.

4. Screwthenewtierodendintothetube(Figure3).Tierodendthreadsmustbevisibletheentirelengthofthecrosstubeslot.Thetierodendistobeengagedatleastonethreaddeeperthantheendofthecrosstubeslot.

5. Refertotheadjustmentandcenteringprocedures,forthetypeofassemblyyourareworkingon,coveredinthisdocument.

6. Torquetheclampnutorjamnut(Figure5)tothevehiclemanufacturer’sspecifications.

Figure 5

31

Figure 2

Figure 1

Figure 3

Figure 4

Figure 5

Draglink– One End Adjustable

1. Positiontheroadwheelsstraightahead.

2. Disconnectthedraglinkatthepitmanarmusingtheappropriatetool.

3. Makesurethesteeringgearisoncenterbyaligningthetimingmarksonthehousingandoutputshaft.

4. Loosentheclamponthedraglink.

5. Adjustthedraglinklengthtofittheholesonthepitmanarmandtheaxlesteerarm.

6. Graspthelongsideofthedraglinkwithbothhands(Figure1).Rotateitawayfromyouasfarasitwillgo,thentowardyouasfarasitwillgo.Centerbetweenthesetwopoints.

7. Holdthelongsideinplace.Graspthetierodend(Figure2)androtateittowardyouandawayfromyouasfarasyou.Centerthetierodendbetweenthesetwopoints.

8. Withbothendscentered,tightentheclamp,andtorque(Figure3)tovehiclemanufacturer’sspecifications.

WARNING Iftheclampistack-welded(Figure4),don’tremovethetackweld.Ifremoved,clampingforcewillnotbeenoughtokeepthetierodendthreadsstationary.Lossofsteeringcontrolwillresult.Ifthetackweldedendrequiresreplacement,theentireassemblyneedstobereplaced.

NOTE Iftheclampisfree-to-rotate(Figure5)itcanbetightenedinanypositionproperly,aslongasthereisenoughclearancefromotherparts.

9. Lubricatebothtierodends(unlesstheyarenon-greaseableends)untilyoucanseecleangreasepurgingoutoftheseal.Use#2NLGIGrease.

NOTE Ahandoperatedgreasegunmustbeusedwhenlubricatinglinkage.Powergreasegunsgenerateexcessiveforcethatwilldamagethebootseal.

NOTE Thispurgeisnecessarytoensurecontaminantsareremovedfromsocketassemblies.

32

Draglink– Two End Adjustable


2. Loosentheclampsonthebothendsofthedraglink.

3. Rotatethecentertubeofthedraglink(Figure1)untilthesteeringgearisoncenter(housingandoutputshafttimingmarksaligned).

4. Tightentheclampsandtorque(Figure2)tomanufacturer’sspecifications.






Figure 2

Figure 1

Figure 3

Figure 4

33

Tie Rod Tube Assembly– One End Adjustable


2. Raisethefrontendofthevehiclesothesteeraxletiresareofftheground.

3. Loosentheclamponthetierodtube.

4. Turnthehexadjusteruntilthetoeiscorrect.

WARNING Donotadjustthetierodendtoapositionwhereyoucanseetheendofthetierodendthreadsthroughtheslotinthetube.Ifthesocketthreadedendisvisible,corrosionmayoccurinthetubeandweakenthecomponents.

5. Graspthelongsideofthetierodwithbothhands(Figure1).Rotateitawayfromyouasfarasitwillgo,thentowardyouasfarasitwillgo.Centerthetierodbetweenthesetwopoints.

6. Holdthelongsideinplace.Graspthetierodend(Figure2)androtateittowardyouandawayfromyouasfarasyoucan.Centerthetierodendbetweenthesetwopoints.

7. Withbothendscentered,tightentheclamp,andtorque(Figure3)tovehiclemanufacturer’sspecifications.






Figure 2

Figure 1

Figure 3

Figure 4

Figure 5

34

Tie Rod Tube Assembly– Two End Adjustable

1. Positionroadwheelsstraightahead.

2. Loosentheclampsonbothendsofthetierodtube.

3. Rotatethecentertubeofthetierod(Figure1)untilachievepropertoe-inmeasurementsonthefrontwheels.

4. Tightentheclampsandtorque(Figure2)tomanufacturer’sspecifications.






Figure 1

Figure 2

Figure 3

Figure 4

35

Figure 1

Drop Center Tie Rod Tube Assembly– One End Adjustable

1. Positionroadwheelsstraightahead.

2. Placeajackunderthecenterofthefrontaxle.Raiseupthefrontendofthevehiclesothesteeraxletiresareofftheground.

3. Loosentheclamponthetierodtube.Disconnectthetierodfromthetierodarmattheadjustableend.

4. Adjustthesocketinone-full-turnincrements(Figure1).Reinstallthesocketend,tighten(donottorque)thefasteneraftereachfullturn.

5. Checkthetoe-inmeasurementaftereachfullturnadjustment.Repeatasnecessaryuntilthetoeiscorrect.

6. Graspthelongsideofthetierodwithbothhands(Figure2).Rotateitawayfromyouasfarasitwillgo,thentowardyouasfarasitwillgo.Centerthetierodbetweenthesetwopoints.

7. Holdthelongsideinplace.Graspthetierodend(Figure3)androtateittowardyouandawayfromyouasfarasyoucan.Centerthetierodendbetweenthesetwopoints.

8. Withbothendscentered,tightentheclamp,andtorquetovehiclemanufacturer’sspecifications.






Figure 2

Figure 4

Figure 5

Figure 3

36

TRW AutomotiveCommercial Steering Systems800 Heath StreetLafayette, IN 47904Tel 765.423.5377Fax 765.429.1868www.trucksteering.com© TRW Inc. 2008 TRW800 Rev. 4/08

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