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TAS Steering Gear Service Manual

1. Fluid with air bubbles Automatic Bleed Systems Gears are mounted in such a way that trapped air can be forced out of the system automatically without loosening bleed screw Follow procedure on page 16 Axial In out movement along an axis imaginary straight line on which an object moves Brinelling Dents Date Code Date the steering gear was built J ulian date Discoloration Change in color External Leakage Fluid Leaking out of the system or steering gear Full Turn Hub contacts axle stop Integral Power Steering Steering gear has manual steering mechanism hydraulic control valve and hydraulic power cylinder all within gear housing Impact The application of torques and forces to steering gear components during accidents or other similar events which exceed the hydraulic capacity of the steering gear Internal Leakage Fluid leaking inside the gear Lash Free play Manual Bleed Systems Gears are mounted in such a way that an air pocket could form in one end of the steering gear The bleed screw is positioned so trapped air can be forced out when loosened Follow procedure on page 16 OSHA Occupational Safety and Health Administration Poppets Unloading valves reduce pressure in full turns Relief Valve Limits maximum supply pressure Return Line Line that connects steering gear to reservoir to recirculate hydraulic fluid Rotary Control Valve Control
2. Tools Required Clean cloth Drip pan High pressure fitting Hydraulic fluid Plug Shop towel Hammer J 37073 Screwdriver line High pressure fitting Plug ring Clean cloth Screwdriver Disconnect return 1 Disconnect 2 column Remove dirt amp 3 water seal Remove retaining 4 Disconnect retum line from the steering gear and plug the line Also cap the retum port of the gear with a high pressure fitting Remove the steering column from the gear input Shaft Remove the dirt and water seal from the steering gear Save this seal to match the new seal to the correct size Wipe out the grease and then remove the spiral retaining ring Use a screwdriver inserted into the notch formed in the end of the ring Be careful not to scratch the bore with the screwdriver Replace column 5 _ Slip the steering column back onto the input shaft with the pinch bolt installed but not tightened Wrap exposed 6 Tie or wrap a shop towel around the input shaft area area and place a drip pan under the vehicle to catch the oil Drip pan Shop towel Fill reservoir 7 Add fluid as necessary to the full line on the dip stick Do not mix fluid types Any mixture of fluid types or use of any unapproved fluid could lead to seal deterioration and leaks A leak could ultimately cause the loss of fluid which could resultin a loss of power steering assist Force out the seal 8 With the vehicl
3. the Safety of others the vehicle or the safe operation of the vehicle and c fully inspect and test the TAS steering gear and the vehicle steering system to ensure that the repair or service of the steering gear has been properly performed and that the steering gear and system will function properly Patents TRW Commercial Steering Division TAS power steering gears are covered by several United States and foreign patents either issued or pending TRW Inc 1998 Contents Section 1 Section 2 Section 3 Section 4 Section 5 General Information Directory for Chart Your Way to Easy Steering Users 6 PEO GON Fo EE DO N 7 Oil Flow Illustration AR EE EE RE 8 Geileidl DES Af onk s EG EE ER E GE 9 General Operation ee ee RR EE RR EE ER RR EE ee RR RE ER ee ee EE Ee 10 Approved Hydraulic FluidS is sei ese es ee ES Ge eb Ge Vi ED 11 Gear Specification Numbers c ssssececcsseeeeeseseeeesseseeessaeeeeeees 11 TUE CANE ie PES GE EG NG OE ee ed ke N Ee 12 Standard Gear Exploded VIewW ET N EE Er 13 SWE Paris ESE ea Ge EE ee AG Ee En og N Ee EE 14 Step Bore Gear Exploded VIew EE EE EN 15 NCEP IA LISE ia ee Ge ed N Ke EG 16 Initial Installation Jes Ie S AE ER EN 18 Poppet ele sn Dra a ee OD GE De N ES ee 18 Maintenance TIPS ccssssecccesececceesseeeceesseeeeseeeeeeeseseeesseaseeseeeegs 19 On Vehicle Service Filling and Air Bleeding the System cccccssseecssssseeesse
4. valve worm subassembly and use thick washer and roller bearing only during reassembly Place valve housing in vise Assemble o ring Assemble other o ring and seal ring Install roller thrust bearing and washer Install bearing components 14 15 16 17 17A Place valve housing 5 firmly in a vise so the input shaft valve worm assembly 13 or 13A can be assembled vertically with the worm end up Do not clamp against threaded port hole or relief valve hole sealing faces when placing valve housing in vise Oil and assemble a new o ring 9 into its counterbore in valve housing Lightly oil and assemble new o ring 11 and new Seal ring 10 into the large diameter seal ring groove in valve housing bending and working them in and Smoothing them out as necessary Install roller thrust bearing 15 and then the thick washer 12 Square side out onto input shaft end of input shaft valve worm subassembly seating them against the input shaft thrust face OR Alternate construction TAS65 Assemble spacer Sleeve 14 onto input shaft with radiused side toward valve Make sure sleeve is square As semble thin washer 16 thrust bearing 15 and thick washer 12 onto input shaft behind spacer Sleeve If you are replacing the input shaft valve worm assembly discard Spacer sleeve and thin washer Install seal ring Assemble input shaft valve w orm amp bearing assem bl
5. 4 Or 116 12 point socket Lof dn Torque wrench Torque locknut Lbf ft Torque wrench Check input shaft torque Stake valve housing and locknut Center punch Hammer 136 Socket Lof dn Torque wrench 23 24 25 20 27 Lightly oil and assemble new locknut 18 onto bearing adjuster 17 with radius slightly rounded side down Tighten slightly to keep the bearing adjuster in place Reverse assembly in vise so the worm end is down With an inch pound torque wrench on the input shaft note torque required to rotate the input shaft 360 in each direction Tighten the bearing adjuster to Increase the maximum torque at the input shaft 5 10 IDf ein 5 1 0 Nem over that which was previ ously noted Again reverse the assembly in vise Torque locknut while holding bearing adjuster in position estab lished in step 24 with appropriate adjuster tool When using a torque wrench in locknut tool J 37464 the torque wrench reading should be 112 Ibfeft 152 N em The bearing adjuster locknut and valve housing flange should be flush If not the seal ring 8 or o ring 9 may be out of position which will result in axial lash Recheck input shaft torque It should match torque measured in step 24 Repeat steps 24 and 25 if necessary Stake valve housing into the clockwise most comer of two opposing slots in locknut 18 Stake the locknut into the adjuster 17 in two places 180 apart at
6. 40 Fleetrite PSF Can 990625C2 Texaco TL 1833 Power Steering Fluid Ford Spec M2C138C Union 10W 40 Mack EO K2 Engine Oil Union 15W 40 Unocal Guardol 15W 40 Motor Oil The steering system should be kept filled with one of the above fluids Fluids marked with an asterisk have not been approved for use with TRW s pump Completely flush the steering system with one of the recommended fluids above only Do not mix oil types Any mixture or any unapproved oil could lead to seal deterioration and leaks A leak could ultimately cause the loss of fluid which could result in a loss of power steering assist Specification Numbers The steering gear Specification number and date code are stamped on a machined surface opposite the input shaft of every TAS gear Newer gears include a C serial number ta Step Bore ldentifier _ example date code TAS65001A would be 29097 this means 29097S01B27 Loo y the gear was built on the Date Code Serial Number 290th day of 1997 6 An A included at the end of the specification number indicates a step bore housing Torgue Chart LE pene Torgue Range Dry Torgue Range Lubricated Auxiliary cylinder plug 25 35 Ibf dft 34 48 Nem Ball retum guide cap strap bolts 14 22 bf ft 19 29 Nem Bearing adjuster 11 15 IDf dt 15 20 N em Locknut 101 122 Ibf dt 137 165 Nem M anual bleed screw 40 50 Ibfein 3 1 3 7 Nem Plug auto bleed 38 58 Ibf sft 52 79 Ne
7. Seal 1 Ser Retaining Ring Seal Input Shaft High Temp Seal Ring Valve Housing Seal Ring 2 O ring 2 High Temp Seal Ring O ring Valve Housing High Temp Thrust Washer Thick Thrust Bearing 2 Thrust Washer Thin Bearing Adjuster Adjuster Locknut Balls Seal Cap Ball Retum Guide Cap Torx Screws 2 Cap Strap Ball Retum Guide Strap Grease Fitting Adjusting Screw Sector Shaft Retainer Adjusting Screw J am Nut Vent Plug Side Cover Bleed Screw M anual Plug Auto Bleed Fixed stop screw Auxiliary Port Plug 2 O ring 2 Aux Port Plug O ring Relief Valve Service Poppet Adjusting Screw Service Sealing J am Nut Item Description Seal Ring Valve Housing Teflon Seal Ring O ring Back up Rack Piston Poppet Seat and Sleeve Assy 2 Poppet 2 old design Poppet 2 new design Poppet Spring Push Tube Ball Return Guide Halves 2 R H Roller Bearing Seal 2 Output Gasket Side Cover L H Special Bolts 6 or 8 Side Cover Dirt amp Water Seal Trunnion Retaining Ring Part Number 020251 478044 478060 478050 401637 478076 032823 029123 032200 158 029116 032200 152 400143 070027 400144 400149 027007 213684 X1 478042 400161 020228 400167 037032 021200 062005 G9419666 036201 213705 021397 021426 G9410358 032229 032200 153 021407 025119 TAS 40 032829 032828 032827 409118 A2 040210 040248 401662 080154 40015
8. bearing the housing from the trunnion end of bearing bore until it is seated against the retaining ring Don t push itfarther Be sure the housing is square with the press base and the bearing is not cocked Use the bearing installation end of the tool short end If the bearing removal end of the bearing amp seal tool is used to press in bearing the cage on the new bearing may be damaged Return to step 32 page 44 Roller Bearing Replacement Step Bore Tools Required Materials Required Press J 37071 A TAS65 Step Bore gear Remove roller 1 If roller bearing 37 in housing needs to be replaced bearing if required place the bearing removal end long end of the bearing and seal tool against the trunnion end of the bearing and press it out of the side cover end of the UO bearing bore Discard bearing Press Press in housing 2 Press the roller bearing 37 into the housing from roller bearing the side cover end of the bearing bore until it is seated against the step bore Be sure the housing is Square with the press base and the bearing is not J 37071 A Ee p 9 Press Use the bearing installation end of the tool short end If the bearing removal end of the bearing amp seal tool is used to press in bearing the cage on the new bearing may be If the unmachined trunnion face Is not sduare use shims to square it before pressing in the bearing Return to step 32 page 44 Replace Ho
9. bleed screw 50 eAuxiliary port plugs 54 and o rings 55 If any are damaged go to Replace Housing Ports Plugs and Screws on page 66 If not proceed to the Inspection Section Inspection Make sure all sealing surfaces and seal cavities are free from nicks and corrosion Any nicked or corroded surface requires part replacement to ensure proper sealing Wash all parts in clean OSHA approved solvent Air blow them dry only Because they are flammable be extremely careful when using any solvents Even a small explosion or fire could cause injury or death Wear eye protection and be sure to comply with OSHA or other maximum air pressure requirements Any of the following conditions present in the steering gear indicates impact damage Condition Brinelling Cracks or Breaks Twisted serrations Area e Ball track grooves of rack piston e Ball track grooves of worm screw Bearing area of sector shaft Thrust washers and bearings in valve housing Bearing area of sector shaft Sector shaft teeth Rack piston teeth e Housing Thrust washers and bearings in valve housing e Worm screw Output shaft serrations If one of these conditions is found in one component be sure to inspect all components carefully for signs of impact damage Replace components noted in individual inspection steps below if you suspect impact damage Failure to replace all damaged components could result in a serious vehi
10. contacted b Pull hard on the steering wheel put 40 Ibs rim pull on a 20 dia steering wheel c Release the steering wheel and shut off the engine 9 Loosen the sealing nut and back out the adjusting screw until 1 is past the nut on both the master gear and the rotary cylinder Tighten the sealing nuts against both housings Do not hold the steering wheel at full turn for more than 10 seconds ata time the heat build up at pump relief pressure may damage components 10 a Start the engine and let it idle b Tum the steering wheel in the original direction end of timing mark toward adjusting screw until axle stop contact is made c Hold the steering wheel in this position with 40 lbs rim pull for 10 seconds then release Repeat this hold and release process as many times as necessary while completing steps 11 and 12 first on the master gear then on the rotary cylinder 11 a With steering wheel held at full tum loosen the jam nut on the master gear and hold it in place with a wrench b Tum the adjusting screw in clockwise using finger pressure only don t use a ratchet until the Allen wrench comes to a stop Do not attempt to tum it in farther Pause the tuming in process each time the driver releases the steering wheel Continue tuming only while the wheel is held at full tum c Back off the adjusting screw 3 turns and tighten the sealing nut Torque nut to 33 37 Ibf dt 12 a With
11. either unit has a poppet adjusting screw and sealing nut that need to be replaced remove and discard them 4 Onboth the master gear and the rotary cylinder tum the adjusting screw and sealing nut assembly without rotating the nut on the screw into the housing until the nut is firmly against the housing using a 7 2 allen wrench Tighten the sealing nut against the housing 5 Refill system reservoir with approved hydraulic fluid Do not mix fluid types Mixing of transmission fluid motor oil or other hydraulic fluids will cause seals to deteriorate faster 6 Place a jack under the center of the front axle and jack up the front end of the vehicle so the steer axle tires are off the ground This resetting procedure will work in most cases with at least 134 hand wheel turns from each side of center If you re making a large reduction in wheelcut and this procedure does not work you may have to replace or internally reset the poppets using the procedure de scribed in the Poppet Component section of this Service M anual 7 a Start the engine and let it run at idle speed b Tum the steering wheel in the direction that makes the timing mark on the master gear move toward the adjusting screw just installed Tum in this direction until axle stop contact is made c Pull hard on the steering wheel put 40 Ibs rim pull on a 20 dia steering wheel after the axde Stop is contacted 8 a Turn the steering w
12. gears should be safe and productive A special thanks to our customers who took the time to review this document prior to printing It s a better publication because of your effort Oil Flow Illustration LeftHand Lead Right Hand Lead v NT d _ y SSS q w Mma F E Ea af roe R 3 Right Hand Turn Steering W heel Input Clockwise Rotation Straightline Running No Steering Action Left Hand Turn Steering W heel Input Counter Clockwise Rotation H Supply Pressure H Return Pressure General Design Integral Pow er Steering TAS power steering gears are the latest design in the TRW Commercial Steering Division family of integral hydraulic power steering gears Integral hydraulic power steering means that the gear contains a manual steering mechanism a hydraulic control valve and a hydraulic power cylinder all in a single compact package Rotary Control Valve The rotary control valve combines simplicity of construc tion with desirable performance characteristics The speed at which the driver can tum the steering wheel with power assist is dependent upon the pump flow measured in gallons per minute or liters per minute directed to a cylinder cavity The control valve controls flow through the steering gear The pressure measured in pounds per square inch or bar reduired for the gear to steer the
13. opposite ends of the gears you have a mirror image system If they both point toward the poppet screws or both point toward the end opposite the poppet screws you have a reversed image system EE WEK EE Lower Poppet Upper Poppets H Lower Poppet NE WE Poppet Readjustment Dual Gears Mirror Image Tools Required Materials Required 732 Allen wrench 8 Open end wrench 3 4 Open end wrench 3 4 Socket Lbf eb Torque wrench Hydraulic fluid J ack 1 Set the axle stops to vehicle manufacturer s wheelcut or clearance specifications Start the engine and allow the vehicle to idle for 5 10 minutes to warm the hydraulic fluid Shut off the engine 2 If new poppet adjusting screws and nuts will be used tum each screw into the non sealing end of the jam nut until the drive end of screw is flush with the nut Your steering gear and rotary cylinder will both have either fixed stop bolts or adjusting screws If the adjusting screw Is already part of the gear or cylin der back the nut off of the adjusting screw until it is flush with the end of the adjusting screw 3 Make sure the engine is off and the road wheels are in straight ahead position Remove and discard the poppet fixed stop bolt if equipped and washer if equipped from the lower end of housing on both the gear and the cylinder If
14. steering wheel held at full turn loosen the jam nut on the rotary cylinder and hold it in place with a wrench b Turn the adjusting screw in clockwise using finger pressure only don t use a ratchet until the Allen wrench comes to a stop Do not attempt to tum it in farther Pause the tuming in process each time the driver releases the steering wheel Continue tuming only while the wheel is held at full tum c Back off the adjusting screw 3 4 turns and tighten the sealing nut Torque nut to 33 37 Ibf dt 13 The poppets on both the master gear and rotary cylinder have now been completely reset Lower the vehicle Check the reservoir and fill if required The length of the adjusting screw beyond the nut must be no more than 1 for proper thread engagement NOTE The length of adjusting screw beyond the sealing nut may be different for each vehicle Section 4 Reseal amp Repair ISAS ge N ON 37 PODEC dies EE r satin 45 AE SEP ps ie GREG N RE N Ge 47 Intemal Damage Repair by reference Poppet Component Replacement 55 Valve Housing Worm Screw Disassembly 57 Roller Bearing or Retaining Ring Replacement 64 Roller Bearing Replacement Step Bore Gear 65 Replace Housing Ports Plugs Screws Fittings 66 Final Adjustments asse ge inte ke DE ke 67 Disassembly Preparation Stop the vehicle with wheels pointed straight ahead Clean off all outside
15. stops in either direction Maintenance Tips Never high pressure wash or steam clean a power steering gear while on or off the vehicle Doing so could force contami nants inside the gear and cause it to malfunction Make sure vehicle wheel cut or clearances meet manufacturer s specifications and make sure pitman arm timing marks are aligned properly to prevent internal bottoming of the steering gear Regularly check the fluid and the fluid level in the power steering reservoir Keep tires inflated to correct pressure Never use a torch to remove pitman arm Investigate and immediately correct the cause of any play rattle or shimmy in any part of the steering system Make sure the steering column is aligned properly Encourage drivers to report any malfunctions or accidents that could have damaged steering components Step Bore Gear Corrosion Inhibiting Grease Barrier Say Neve SW Ri TE NAV Dirtand Water Seal High Pressure Output Seal Do not attempt to weld any broken steering component Replace the component with original eduipment only Do not cold straighten hot straighten or bend any steering system component Always clean off around the reservoir filler cap before you remove it Prevent dirt or other foreign matter from entering the hydraulic system Investigate and correct any external leaks no matter how minor Replace reservoir filters according to requirements If you feel the
16. threaded area Choose areas that have not been previously staked After staking torque required to rotate input shaft must be between 5 10 Ibfein 5 1 0 Nem greater than the torque noted in step 24 Torque value must not exceed 22 Ibfein 2 5 Nem Unstake and readjust if necessary Reposition 28 Reposition worm screw valve housing subassembly subassembly in in soft jawed vise clamping tightly against valve vise housing so the wom screw is pointing down Install input shaft 29 Apply clean grease Exxon Unirex RS460 to the seal outside and inside diameters fill cavity between the lips of the new input shaft seal 4 and assemble it 37073 garter spring side first over the input shaft Align Hammer Seal in the valve housing seal bore Assemble seal installer tool 4 37073 small diameter end first over the input shaft and against the seal Tap the seal installer tool until the tool shoulder is Squarely against the valve housing This will cor rectly position the seal in the housing bore just beyond the retaining ring groove Remove any seal material that may have sheared off and is in seal bore and retaining ring groove The input shaft seal must be square in the seal bore and installed to the correct depth Insert retaining 30 Insert new retaining ring 3 into its groove in valve ring housing Install dirt amp water 31 Pack the end of the valve housing bore around the seal input shaft with clean high te
17. to vehicle manufacturer s recommendation Install pitman arm on output shaft with timing marks aligned Torque bolt to vehicle manufacturer s recommendation Connect drag link to pitman arm Poppet Resetting removed from vehicle and gear is being installed on the Same vehicle with no change in axle stops or linkage both tums just before axle stop contact is made If not use resetting procedure beginning on page 28 gt gt IF Poppets were replaced with new components or Use poppet setting procedure on page 18 reset during gear disassembly and are ready for auto matic positioning gt gt IF Poppets may have been moved during disassembly Use poppet resetting procedure beginning on page 28 or reassembly procedures or gear is being installed on a different vehicle gt gt Maintenance Tips Never high pressure wash or steam clean a power steering gear while on or off the vehicle Doing so could force contami nants inside the gear and cause it to malfunction Make sure vehicle wheel cut or clearances meet manufacturer s specifications and make sure pitman arm timing marks are aligned properly to prevent internal bottoming of the steering gear Regularly check the fluid and the fluid level in the power steering reservoir Keep tires inflated to correct pressure Never use a torch to remove pitman arm Investigate and immediately correct the cause of any play rattle or shimmy in any part of the st
18. using only a hand operated grease gun Add grease until it begins to extrude past the dirt and water seal Do not use a power grease gun because it will supply grease too fast this could adversely affect the high pressure seal and contaminate the hydraulic fluid Poppet Readjustment Single Gears Tools Required Materials Required 732 Allen wrench 8 Open end wrench 4 Open end wrench 3 4 Socket Lbf eb Torque wrench Hydraulic fluid J ack Set axle stops 1 warm up system Assemble adjust 2 ing screw into nut Remove poppet 3 stop bolt Open end wrench Turn adjusting 4 screw assembly into housing This resetting procedure will work in most cases with at least 134 hand wheel turns from each side of center If you re making a large reduction in wheelcut and this procedure does not work you may have to replace or internally reset the poppets using the procedure de scribed in the Poppet Component section of this Service M anual Set the axle stops to vehicle manufacturer s wheelcut or clearance specifications Start the engine and allow the vehicle to idle for 5 10 minutes to warm the hydraulic fluid Shut off the engine If anew poppet adjusting screw and nut are being used tum the screw into the non sealing end of the jam nut until the drive end of screw is flush with the nut Your steering gear will have either a fixed stop bolt or an adjusting screw If the a
19. vehicle is created by the power steering pump to overcome resistance at the steered wheels The control valve senses these requirements and directs fluid to the appropriate cylinder Cavity in the steering gear and in the auxiliary cylinder if it Is a dual steering system at the proper flow rate and pressure Pressure Means Work Flow Means Speed The higher pressure a steering gear can withstand the more work it can perform The maximum operating pressure for all TAS gears is 2 175 psi 150 bar maxi mum flow rate for all TAS gears is 8 gal min 30 3 L min The TAS series gears can steer a vehicle within its front end weight rating through a turn at low speed and engine idle As the driver turns the steering wheel faster or Slower more or less fluid will be required by the gear TAS series vehicle front end weight ratings are as fol lows Front Axle Rating 9 000 Ib 4 100 kg 12 000 Ib 5 400 kg 14 300 Ib 6 500 kg 18 000 Ib 8 200 kg The recommended minimum flow at 1 steering wheel turns per second is as follows Gear Minimum Flow Rate 2 2 gal min 8 3 L min 2 6 gal min 9 8 L min 3 0 gal min 11 4 L min 3 6 gal min 13 6 L min If the steering gear valve is controlling an auxiliary cylin der increased minimum flow is required generally at least 75 based on the size of the auxiliary cylinder and the vehicle s steering geometry Maximum internal leakage for all TAS gears is 1 gal min Gener
20. 00159 401674 070030 478052 478053 028527 478051 HFB529000 021277 Parts Vary by Specification Item Description 5 Valve Housing 13 Input Shaft Valve Worm Assy 13A Input Shaft Valve Worm Assy Alt 14 Spacer Sleeve Alt 19 Rack Piston 34 Housing 42 Sector Shaft 46 Side Cover Assembly 56 Relief Valve Cap 58 Relief Valve 2 piece Contact Service Sales for part numbers Applicable to TAS65 gears only Kits Items Description Part Number 54 amp 55 Port Plug amp O ring 415437 A1 56 amp 57 Relief Valve Cap amp O ring 411061 A1 59 amp 60 Adj Screw amp am Nut 021407 X1 2 2B 2C 3 4 Input Shaft Seal Kit TAS000001 TAS40 Seal Kit TAS400003 TAS55 Seal Kit TAS550004 TAS65 Seal Kit TAS650012 TAS85 Seal Kit TAS850003 or 4 TAS55 TAS65 TAS85 032829 032616 032834 032830 032590 032547 032831 032615 032556 409118 A2 409118 A2 409118 A6 040210 040210 040217 040248 040248 040249 401662 401662 401684 040209 040209 040218 080154 080154 080158 400160 400156 400162 400165 400157 400163 401650 401650 401685 071032 071033 072004 478041 478041 478057 478045 478045 478059 028519 028519 028534 478040 478040 478084 HFB649000 HFB649000 TAS859000 021434 021434 021434 TAS Series Exploded View Step Bore 52A 52 53 od 59 60 2 z O Description Bolts 4 Valve Housing Dirt and Water Seal 13 16 Serr Dirt and Water Seal 7 8 Serr Dirt and Water Seal 1 Serr Retaining Ring S
21. 8 400159 070030 478051 HFB529000 021277 K301963 401674 Parts Vary by Specification Item Description 5 _ Valve Housing 13 Input Shaft Valve Worm Assy 19 Rack Piston 34 Housing 42 Sector Shaft 46 Side Cover Assembly 56 Relief Valve Cap 58 Relief Valve 2 piece Contact Service Sales for part numbers Kits Items 54 amp 55 56 amp 57 59 amp 60 2 2B 2C 3 4 TAS55 032829 032830 032831 409118 A2 040210 040248 401662 080154 400160 400165 071032 478040 HFB649000 G223734 478095 401650 Description Port Plug amp O ring Part Number 415437 A1 Relief Valve Cap amp O ring 411061 A1 Adj Screw amp J am Nut Input Shaft Seal Kit TAS40 Seal Kit TAS55 Seal Kit TAS65 Seal Kit TAS85 Seal Kit TAS65 032616 032590 032615 409118 A2 040210 040248 401662 080154 400156 400157 071033 478040 HFB649000 G223734 478095 401650 021407 X1 TASOOOOO1 TAS400003 TAS550004 TAS650012 TAS850003 or 4 TAS85 032834 032547 032556 409118 A6 040217 040249 401684 080158 400162 400163 072004 478084 TAS859000 G223734 478096 401685 Section 2 Initial Installation VREES Ee a O E E E T 18 PODDEE Std ae ER EN ee ae ON Ee 18 Maintenance TIPS ae DE ER ee Ge Gee 19 4 Initial TAS Installation e Bolt gear to frame torque to vehicle manufacturer s recommendation e Connect retum line to TAS return port e Connect hydraulic line from pump to pressure port
22. age 45 Final Adjustments Tools Required Materials Required Box end Screwdriver wrench Sockets Lbf ft Torque wrench Lof dn Torque wrench Ed Center steering 1 _ To center the steering gear rotate input shaft valve gear worm assembly 13 or 13A until the timing mark on the end of the sector shaft 42 is in line with the and Mier timing mark on the end of housing trunnion Socket or box end wrench Do not rotate the input shaft more than 1 5 revolutions from center position until the steering gear is installed during poppet setting procedure Doing so could make the automatic poppets inoperative which would require disassembly of steering gear to reposition poppet seat and sleeve assemblies Initial poppet contact will occur at less than one input shaft rotation in one direction from steering gear center position if new or reset poppet adjuster seat and Sleeve assemblies are assembled in the unit Worm preload adjustment was set when input shaft valve and worm were assembled into valve housing Tighten adjusting 2 With adjusting screw jam nut 47 loose tum sector m d screw shaft adjusting screw 43 clockwise to provide 45 50 lbfein 5 5 5 Nem of torque required to rotate the input shaft valve worm assembly 13 or 13A through one half turn 180 each side of center Lbfein Torque wrench Screwdriver LY 6 or 3 4 This procedure will properly Socket mesh and seat the
23. al 1 Serr is Teflon Seal Ring 47 JamNut 3 Retaining Ring 21 O ring Back up Rack Piston 48 Special Bolts 6 or 8 Side Cover 4 Seal Input Shaft 22 Poppet Seat and Sleeve Assy 2 49 Vent Plug Side Cover 5 Valve Housing 23 Poppet 2 50 Bleed Screw Manual 6 Seal Ring Valve Housing 24 Poppet Spring 51 Plug Auto Bleed 7 Seal Ring Valve Housing 25 Spacer Rod 52 Fixed Stop Screw Poppet 8 Seal Ring 2 26 Push Tube 52A Fixed Stop Screw Poppet Alt 9 O ring 2 27 Balls 53 Washer Stop Screw 10 Seal Ring oo Ball Return Guide Halves 2 54 Auxiliary Port Plug 2 11 O ring Valve Housing 29 Seal Cap _ 55 O ring 2 Aux Port Plug 12 Thrust Washer Thick ee MEE 56 Relief Valve Cap 13 Input Shaft Valve Worm Assy a Torx Screws 2 Cap Strap 57 O ring Relief Valve 13A Input Sh Valve Worm Assy Alt 32 Ball Return Guide Strap 58 Relief Valve 2 piece 14 Spacer Sleeve Alt 34 Housing _ 59 Service Poppet Adjusting Screw 15 Thrust Bearing 1 or 2 35 Grease Fitting 60 Service Sealing J am Nut These items are included in complete seal kits along with 406038 lubricant and a service bulletin Service Parts List Standard Common Parts Item Description 1 Bolts 4 Valve Housing 2 Dirt and Water Seal 13 16 Serr 2B Dirt and Water Seal 7 8 Serr 2C Dirt and Water Seal 1 Ser 3 Retaining Ring 4 Seal Input Shaft High Temp 7 Seal Ring Valve Housing 8 Seal Ring 2 9 O ring 2 High Temp 10 Seal Rin
24. al Operation W hat Happens During a Steering M aneuver When the driver tums the steering wheel he transmits force from the steering wheel to the steering gear input shaft A torsion bar pinned at its one end to the input shaft and at its other end to the worm shaft tums with the input shaft and exerts a rotational force on the worm Shaft In response to this rotational force the worm Shaft acting through the recirculating ball mechanism tries to move the rack piston axially through the gear housing cylinder bore The rack piston s axial movement is resisted by its engagement to the sector shaft which is connected by linkage to the steered wheels Because of this resis tance the torsion bar is twisted by the input shaft thereby actuating the control valve Pressurized fluid directed by the control valve assists in moving the rack piston axially through the cylinder bore The rack piston then tums the sector shaft to steer the vehicle Shock Loads to the Gear If the steered wheels receive a shock load the shock forces are transmitted through the sector shaft to the rack piston and on to the wom shaft The internal geometry of the steering gear causes the control valve to send high pressure fluid to the correct cylinder cavity to resist the shock forces By absorbing the shock forces hydraulically the steering gear prevents objectionable kickback at the steering wheel Unloading Poppet Valves Most TAS gears are equipped wi
25. allow the fluid level to drop significantly or run out of the reservoir This may induce air into the system Run engine for 2 2 Start the engine and let it idle for 2 minutes Do not minutes turn off steer Shut off the engine and check the fluid level and fill reservoir in the reservoir Refill as required Hydraulic fluid V Steer vehicle 3 Start the engine again Steer the vehicle from full i e left to full right several times Add fluid as neces H sary to the full line on the dip stick Automatic bleed systems should now be free from trapped air Manual bleed systems continue with step 4 Auto Bleed Plug Do Not Remove Allow airto bleed 4 With engine idling steer from full left turn to full outfrom bleed right turn several times Stop steering and loosen screw the manual bleed screw about one tum Allow air and aerated fluid to bleed out until only clear fluid is seen Close the bleed screw refill the reservoir if required M anual Bleed Screw Lbfein Torque wrench 716 Socket Repeat step 4 three to four times until all the air is discharged Torque manual bleed screw to 45 Ibf n Mi Do not turn steering w heel with bleed screw loosened Input Shaft Seal Replacement This procedure uses the vehicle s power steering pump to force out the input shaft seal To use this procedure the power steering pump should have a minimum of 1 500 psi available Materials Required
26. asier or quicker Disclaimer This Service M anual has been prepared by TRW Commercial Steering Division for reference and use by mechanics who have been trained to repair and service steering components and systems on heavy commercial vehicles TRW Commercial Steering Division has exercised reasonable care and diligence to present accurate clear and complete information and instructions regarding the TRW Commercial Steering TAS Series Integral Power Steering Gears Since this is a general Service M anual the photographs and illustrations may not look exactly like the steering gear being ser viced The procedures therefore must be carefully read and understood before Servicing If inspection or testing reveals evidence of abnormal wear or damage to the TAS steering gear or if you encounter circumstances not covered in the M anual Stop Consult the vehicle manufacturer s Service Manual and warranty Do nottry to repair or service a TAS steering gear which has been damaged or includes any part that shows exces sive wear unless the damaged and worn parts are replaced with original TRW replacement and service parts and the unit is restored to TRW s specifications for the TAS steering gear It is the responsibility of the mechanic performing the maintenance repairs or service on a particular TAS steering gear to a inspect the steering gear for abnormal wear and damage b choose a repair procedure which will not endanger his her safety
27. ble hazard notices Some of the major changes are e Revised caution and warning definitions that conform to international standards e Revised torque force pressure and flow notations that conform to intema tional standards e Service Manual divided into sections for easier reference e Directory for Chart Your Way to Easy Steering users to speed service of correctly diagnosed problems e Uninterrupted resealing instructions Reference to damage section allows you to repair or replace damaged parts and return to the resealing proce dures easily e Binding process that better allows the Service M anual to lay flat The three column format used in the Service M anual will also help make it easy for you to service a steering gear Column 1 illustrates the procedure with photographs column 2 gives a brief key as well as tools to be used for each procedure and column 3 explains in detail the procedure you should follow Pay special attention to the notes cautions and warnings Item numbers on the exploded view correspond with item numbers used throughout the Service M anual As you gain expenence in servicing TAS steering gears you may find that some information in this Service M anual could be clearer and more complete If so let us know about it Don t try to second guess the Service M anual if you do not under Stand a procedure or are stuck contact our Field Service Department at 317 423 5377 Servicing TAS series steering
28. cle accident Inspect rack piston teeth Inspect rack piston and worm ball track grooves 1 Inspect the rack piston 19 teeth for cracks or obvious damage If teeth are damaged replace the rack piston sector shaft 42 and set of balls 27 2 Inspect the rack piston 19 ball track grooves for brinelling or spalling If either condition exists replace the input shaft valve worm assembly valve housing rack piston subassembly and balls Inspect input shaft valve w orm assembly sealing areas Inspect housing cylinder bore Inspect housing faces Inspect side cover bushing bearing Inspect sector shaft assembly 3 4 5 6 7 Inspect the sealing area of input shaft and valve 13 or 13A for nicks and damage Inspect for discolora tion from excess heat Inspect input shaft ball track grooves for brinelling or spalling If any of these conditions exist replace the input shaft valve worm assembly valve housing and balls Also replace rack piston if brinelling or spalling is found Inspect the housing 34 cylinder bore some scoring marks are normal If there was internal leakage greater than 1 gal min make sure there are no damaged seals before replacing the housing Inspect the housing faces for nicks that would prevent proper sealing Replace the gear housing if these nicks are present and cannot be easily re moved with a fine tooth flat file without changing t
29. crew 31 4 tums and tighten the sealing nut Torque the sealing nut to 33 37 Ibf ft d Release the steering wheel and shut off the engine Loosen the sealing nut and back out the adjusting screw on the rotary cylinder until 1 is past the nut Tighten the sealing nut against the housing a Start the engine and let it idle b Tum the steering wheel in the opposite direction end of timing mark on master gear away from adjusting screw until axle stop contact is made c Hold the steering wheel in this position put up to 40 Ib nm pull on a 20 dia steering wheel for 10 seconds then release Repeat this hold and release process as many times as necessary while completing step 14 a With steering wheel held at full turn loosen the jam nut on the rotary cylinder and hold it in place with a wrench b Turn the adjusting screw in clockwise using finger pressure only don t use a ratchet until the Allen wrench comes to a stop Do not attempt to tum it in farther Pause the tuming in process each time the driver releases the steering wheel Continue tuming only while the wheel is held at full tum c Back off the adjusting screw 3 turns and tighten the sealing nut Torque the sealing nut to 33 37 Ibf ft d Release the steering wheel and shut off the engine The poppets have now been completely reset Lower the vehicle Check the reservoir and fill if required The length of the adjusting screw beyond the nut m
30. cted Check for sector 3 From the center of travel position grasp the shaftlash pitman arm and gently try to rotate it back and forth If looseness or lash is felt at this point the sector Shaft is out of adjustment Loosen jam nut 4 Loosen the jam nut 7 4 Socket If the gear is removed from the vehicle to adjust the lash e Leave the pitman arm connected to the gear Best option is to follow the Final Adjustment procedure on page 67 Alternate option is to continue with step 5 of this procedure j Ja Position adjusting 5 If no lash was detected in step 3 tum the shaft el screw adjusting screw counterclockwise until you feel lash at the output shaft Adjust shaft 6 Slowly tum the shaft adjusting screw clockwise until you feel no lash at the output shaft without using more than 10 lbf ft 14 Nem of torque From this position tum the screw clockwise 1 2 to 3 of a tum more Hold the adjusting screw in place and tighten the jam nut Final jam nut torque 43 Ibf ft 58 Nem Screwdriver 4 Open end wrench Recheck for lash 7 _ Tum the steering wheel tum each side of center then back to center and recheck the pitman arm for lash You should feel no lash if there is lash repeat Steps 4 6 and 7 Connect drag link 8 Reconnect the drag link to the pitman arm according to manufacturer s specifications Maintain grease in the sector shaft bearing through the grease fitting in the housing
31. dirt from around fittings and hose connections before you remove the gear Remove input and output shaft connections per vehicle manufacturer s instructions When using a chisel to spread a pinch bolt type pitman arm boss for assembly or removal from the shaft maintain a firm grip on the chisel at all times Failure to do this may result in the chisel flying loose which could cause an injury Never leave the chisel wedged in the pitman arm boss If you cannot remove the pitman arm from the shaft with a chisel and your hands remove the chisel from the arm boss and use a puller only to remove pitman arm Do not use a hammer on the pitman arm to remove it from sector shaft as internal damage to steering gear could result Be sure there is no spreading wedge left in the pitman arm boss before tightening pitman arm clamp bolt after assembly on sector shaft Do not pound the universal joint or input shaft coupling on or off the input shaft as internal damage to the steering gear can result Unless the poppet adjuster seat and sleeve assemblies 22 are to be removed and replaced or reset for automatic poppet adjustment or a manual adjustment with a service poppet adjuster screw 59 and nut 60 is anticipated do not allow the input shaft on a steering gear with the automatic poppet adjustment feature to rotate more than 1 5 input shaft revolutions from straight ahead position when the output shaft is disconnected from the vehicle steering linkage
32. djusting screw is already part of the steering gear back the nut off of the adjusting screw until it is flush with the end of the adjusting screw Make sure the engine is off and the road wheels are in straight ahead position Remove and discard the poppet fixed stop bolt if equipped and washer if equipped from the lower end of the housing If the unit has a poppet adjusting screw and sealing nut that need to be replaced remove and discard them Tum the adjusting screw and sealing nut assembly without rotating the nut on the screw into the housing until the nut is firmly against the housing using a 72 Allen wrench Tighten the sealing nut against the housing If the drive end of the screw is below the face of the nut the popet seat flange will break during step 7d Refill reservoir 5 Refill the system reservoir with approved hydraulic fluid Hydraulic fluid Do not mix fluid types Mixing of transmission fluid motor oil or other hydraulic fluids will cause seals to deteriorate faster Jack up vehicle 6 Place a jack under the center of the front axle and jack up the front end of the vehicle so the steer axle Jacko tires are off the ground Push upper poppet 7 a Start the engine and let it run at idle speed out to prepare it for h b Note which output shaft timing mark is nearest setting the housing piston bore c Turn the steering wheel in the direction that makes this timing mark move towa
33. e ball track guide path Continue until the correct number of balls are in the ball track guide path Hold down the ball return guides until cap or clip is reinstalled Failure to hold the guides will result in a trapped ball or balls which could cause a vehicle accident If the ball guides become unseated raise up at any time repeat the procedure starting at step 9 The correct number of balls are required for proper gear operation Count the balls and insert each carefully as in step 11 TAS55 TAS65 Original 30 31 32 Service 31 32 TAS55 gears built prior to 338 89 were equipped with 30 balls Do not allow valve housing to contact the poppet stem or move more than 2 inches 69 1 mm from upper end of rack piston during these procedures This could incorrectly reset the poppet or back out worm beyond closed ball loop trapping balls Remove any fluid presentin the two screw holes Fluid in these holes could cause improper clamp load when torquing the cap or strap screws Assemble ball 13 Place anew ball retum guide cap seal 29 in the return guide cap seal groove of the cap 30 Make sure the seal makes full contact with the rack piston surface 549 Allen or T Install two new Allen or Torx head screws 31 and 30 Torx socket torque each screw alternately until a final torque of Lbf in Torque 18 Ibfeft 24 5 Nem is achieved wrench Grease Ball cap seal is greased
34. e by hand with no perceptible end play lash Remove relief valve components Ver Socket Remove dirt amp water seal Clean input shaft Fine grade emery cloth Remove valve housing bolts Torx socket E 16 or E 18 Remove valve housing w orm and rack subassembly 15 If equipped remove relief valve cap 56 o ring 57 and two piece relief valve 58 from the valve housing Discard the o ring 16 Remove and discard the dirt amp water seal 2 2B or 2C from the input shaft 13 or 13A Save this seal for comparison with the new seal 17 Clean any paint or corrosion from the exposed area of the input shaft 18 Remove the four torx head valve housing bolts 1 19 Be prepared for more fluid drainage and remove the rack piston subassembly Place the assembly ona clean cloth For the TAS85 it may help to rotate the input shaft to move the rack piston toward the lower end of the housing This will force the valve housing to exit the main housing The set position of poppet seat and sleeve assemblies 22 must not be disturbed if the poppets are not going to be replaced or reset during disassembly Pocket knife 19A Remove seals 20 Remove ball return 21 n guide cap strap 32 Allen wrench or T 30 Torx wrench Remove ball return 21A guide clip 1 2 Socket in Remove ball return 22 Tr guides Screwdriver If your gear is short V construction the rack p
35. e in neutral momentarily tum the Starter quickly tum off the engine if it starts Remove inputshaft 9 Remove the shop towel Disconnect the steering seal column and remove the input shaft seal Inspect seal area 10 Inspect old seal 11 Install new seal 12 Hammer J 37073 Install retaining 13 ring Install dirt amp water 14 seal Check the seal area of the valve housing for any seal fragments Remove any that are found Check the seal for heat damage If the seal is stiff and brittle and not pliable like the new seal it is probably heat damaged Determine and fix the cause of excessive heat in the vehicle Put clean grease 406038 on the inside dia of the new input shaft seal and place it over the input Shaft With the small dia of tool J 37073 against the Seal tap the tool until the tool shoulder is square against the valve housing Remove any seal material that may have sheared off in the seal bore or retaining ring groove Do not use a socket to install this seal because you will not be able to control seal installation depth possibly causing a leak Insert new retaining ring into the groove Pack the end of the valve housing bore around the input shaft with grease 406038 Choose the correct size dirt amp water seal by comparing the choices to the old seal or by measuring the major diameter of the input shaft serrations see chart next page Apply more grease 406038 to the new dirt a
36. e screw into the housing until the nut is firmly against the housing on both the master gear and the rotary cylinder using a 72 allen wrench Tighten the sealing nut against the housing 5 Refill system reservoir with approved hydraulic fluid Do not mix fluid types Mixing of transmission fluid motor oil or other hydraulic fluids will cause seals to deteriorate faster 6 Place a jack under the center of the front axle and jack up the front end of the vehicle so the steer axle tires are off the ground This resetting procedure will work in most cases with at least 134 hand wheel turns from each side of center If you re making a large reduction in wheelcut and this procedure does not work you may have to replace or internally reset the poppets using the procedure de scribed in the Poppet Component section of this Service M anual 7 a Start the engine and let it run at idle speed b Note which output shaft timing mark is nearest the housing piston bore c Turn the steering wheel in the direction that makes this timing mark move toward the adjusting screws just installed on both the gear and the cylinder Tum in this direction until axle stop contact is made d Pull hard on the steering wheel put 40 Ibs rim pull on a 20 dia steering wheel after the axle Stop is contacted 8 a Tum the steering wheel in the opposite direction end of timing mark away from adjusting screw until the other axle stop is
37. e them and call TRW for disposition Do not rebuild the gear ieee Remove seal rings 9 and o rings Small probe or pick Remove retaining 10 ring Screwdriver Remove seal 11 14 Socket Hammer Inspectinput shaft 12 valve worm assembly sealing areas Inspect thrust 13 washers and bearings Remove and discard seal rings 10 and 8 and o rings 11 and 9 from valve housing 5 Tum over valve housing and remove retaining ring 3 Exercise special care when removing seal 4 to prevent damaging the valve housing seal bore Tap input shaft seal 4 out of valve housing Dis card seal The valve housing also utilizes a ball plug for manufacturing purposes that must not be removed Inspect the sealing areas of input shaft and valve 13 or 13A for nicks and run your fingemail edge across the sealing surfaces to detect steps Inspect for discoloration from excess heat Inspect input shaft ball track grooves for brinelling or spalling If any of these conditions exist you must replace the input Shaft valve worm assembly valve housing and balls Also replace rack piston if brinelling or spalling Is found Inspect the thrust bearing 15 rollers for any deterio ration Inspect thrust washers 12 amp 16 for brinelling spalling or cracks Replace any part with these conditions Alternate Construction TAS65 If spacer sleeve 14 is damaged replace the input shaft
38. eal Input Shaft Valve Housing Seal Ring Valve Housing Seal Ring Valve Housing Seal Ring 2 O ring 2 Seal Ring O ring Valve Housing Thrust Washer Thick Input Shaft Valve Worm Assy Thrust Bearing 1 or 2 Thrust Washer Thin Bearing Adjuster Adjuster Locknut Rack Piston Teflon Seal Ring O ring Back up Rack Piston Poppet Seat and Sleeve Assy 2 Poppet 2 Poppet Spring Push Tube Balls Ball Retum Guide Halves 2 Seal Cap Ball Retum Guide Cap Torx Screws 2 Cap Strap Ball Retum Guide Strap Housing Grease Fitting Roller Bearing 63 Seal 2 Output Sector Shaft Adjusting Screw Sector Shaft Retainer Adjusting Screw Gasket Side Cover Side Cover Assembly J am Nut Special Bolts 6 or 8 Side Cover Vent Plug Side Cover Bleed Screw M anual Plug Auto Bleed Fixed Stop Screw Poppet Fixed Stop Screw Poppet Alt Washer Stop Screw Auxiliary Port Plug 2 O ring 2 Aux Port Plug Relief Valve Cap O ring Relief Valve Relief Valve 2 piece Service Poppet Adjusting Screw Service Sealing J am Nut Dirt amp Water Seal Trunnion Retaining Ring These items are included in complete seal kits along with 406038 lubricant and a service bulletin Service Parts List Step Bore Common Parts Item Description 1 2 2B 2C Parts Vary by Gear Size Bolts 4 Valve Housing Dirt and Water Seal 13 16 Serr Dirt and Water Seal 7 8 Serr Dirt and Water
39. eering system Make sure the steering column is aligned properly Encourage drivers to report any malfunctions or accidents that could have damaged steering components Step Bore Gear Corrosion Inhibiting Grease Barrier PYLE SR WSR ESE J N NAR Dirtand Water Seal High Pressure Output Seal Do not attempt to weld any broken steering component Replace the component with original eduipment only Do not cold straighten hot straighten or bend any steering system component Always clean off around the reservoir filler cap before you remove it Prevent dirt or other foreign matter from entering the hydraulic system Investigate and correct any external leaks no matter how minor Replace reservoir filters according to requirements If you feel the vehicle is developing excessively high hydraulic fluid temperatures consult with your vehicle manufacturer for recommendations Maintain grease pack behind the output shaft dirt and water seal as a general maintenance procedure at least twice a year in the Spring and Fall Grease fitting is provided in housing trunnion Use only NLGI grade 2 multipurpose chassis lube and use only a hand operated grease gun on fitting Add grease until it begins to extrude past the sector shaft dirt and water seal af a E a Corrosion Inhibiting Grease Barrier KJ L 7 Nama Ver A hN INNAN NANI Bearing High Pressure Output Seal Glossary Aerated Fluid
40. el is svkr EE ee ge a 10 Approved Hydraulic FIUIOS ees sees see ee ee ee EE ee ee Ee 11 Gear Specification Numbers ies sees ee EE RE Ee Re EE ee 11 Tord ELE se E l NG ee a 12 Standard Gear 25 49 810 29 VIE N ne RE Ge N ee eg N EG 13 Service Parts LISE see ee EE EA eg ED ER DE EN ee 14 Step Bore Gear Exploded VIEW eN Ne be Eb dee ee 15 Service Parts LISE ee ee ee ee ee ee ee ee ee ee 16 Chart Your Way to Easy Steering Directory Chart Your Way to Easy Steering is a separate publication actually a Manual Flow Charts and two Videotapes that facilitates troubleshooting steering system complaints If while using this tool your system has failed one or more tests you probably have been directed to this Service M anual for repairs The following directory will help you locate the specific repairs you will need to make to proceed with the Chart Your Way to Easy Steering process Use Example The driver of the vehicle you are working on complains of Steering Wheel Kick You have first determined using Chart Your Way to Easy Steering that there is no air in the system The book then directs you to perform test 18 to check for lash in the system While performing this test you detected lash or lost motion from the input shaft to the output Shaft Since this looseness Is inside the steering gear you would refer to this Service M anual and locate the test number of the failed test test 18 The problem listed be
41. ep may have already been completed if you disassembled the valve housing and worm screw for repair Proceed to Final Adjustments on page 67 Trademark of Exxon Oil Corp Poppet Component Replacement Tools Required Materials Required 2 Ib Sledge Ratchet Locquic T primer Lbf dt Torque Soft jawed vise Loctite RC680 wrench J 36452 A Press 3 2 x 6 drill rod Place rack piston 1 If the poppet assemblies are to be removed for in vise replacement place rack piston in a soft jawed vise Soft jawed vise Loosen poppet 2 Slide special tool 4 36452 A over the seat of poppet adjuster seat adjuster seat and sleeve assembly 22 and engage tool in the slots in the threaded sleeve Hit the end of the tool firmly four or five times with a 2 Ib sledge hammer to loosen Loctite J 36452 A 2 Lb Sledge t Poppet adjuster seat and sleeve gt assemblies 22 are retained by Loctite applied to the threads which makes the assem blies difficult to remove Remove poppet 3 With a ratchet applied to the tool tum one adjuster adjuster seat seat and sleeve assembly out of the rack piston If the ratchet does not turn easily strike the adjuster removal tool again with ahammer If the engaging J 36452 A i a E tangs won t stay in place while torquing it might be necessary to hold in place with an arbor press while applying loosening torque Discard poppet seat and sleeve assembly Remove poppet 4 Remove the t
42. ew jam nut 47 onto the sector shaft adjusting screw 43 a few threads Final adjustment will be made later Assemble vent 24 Press the new vent plug 49 into the hole provided plug in the side cover until the plug is bottomed Do not weld or otherwise plug this hole in any permanent manner This is a Safety vent which functions only if the side cover seal fails If the seal fails and the plug cannot vent the steering gear may lock up or otherwise malfunction Install side cover 25 Apply clean grease to the new side cover gasket gasket 45 to hold it in place and assemble it onto the side cover 46 Center rack piston 26 There are four teeth on the rack piston Rotate input Shaft to position the rack piston so the space between the second and third tooth is in the center of the sector shaft opening This will center the rack piston for assembly of sector shaft If the rack piston is not centered when sector shaft is installed gear travel will be severely limited in one direction This could result in an accident Install sector shaft 27 Clean off any old tape on the serrations Reapply and side cover into one layer of masking tape Install the sector shaft housing assembly into the housing The center tooth of the sector shaft must engage the center space be Masking tape tween the second and third tooth of the rack piston with side cover gasket in place If the serrations are not properly taped the
43. ft with one layer of masking tape The tape Should not extend onto the sector shaft bearing diameter Remove the sector shaft adjusting screw jam nut 47 Be prepared for more fluid drainage and remove the SIX or eight special bolts 48 from the side cover 46 Be prepared for more fluid drainage and remove the Side cover and sector shaft assembly from the gear You may start the shaft and cover assembly removal by tapping the end of the shaft lightly with a soft mallet or wooden hammer handle Discard gasket Remove vent plug Remove sector shaft from cover Screwdriver seal 3 8 Drive socket Rolling head pry Inspect adjusting 14 screw and retainer Remove side cover 13 10 Remove and discard the side cover gasket 45 11 Remove and discard the vent plug 49 12 Screw sector shaft adjusting screw 43 clockwise through the side cover and pull the sector shaft out of the side cover Don t damage the bore or DU bushing when removing the seal TAS85 gears are not equipped with the DU bushing Clamp the side cover in a vise Place a standard 375 or 116 3 2 drive socket in the center of the side cover pry the seal 41 out with a rolling head pry bar using the socket for Support Discard the seal and remove the socket Inspect the sector shaft assembly for damaged adjusting screw threads The retainer 44 must be securely staked in place The adjusting screw must rotat
44. fully apply Loctite RC680 to same threads Locquic T primer Do notallow Loctite or Locquic to get on the adjuster seat component of the adjuster seat and sleeve assembly The poppets will not function properly Loctite RC680 Install one poppet 8 Wear eye protection while seat and sleeve assembling poppets as spring assembly loaded poppets could eject and cause eye injury soft Jaw ed vise Place rack piston 19 in a soft jawed vise and tum one new poppet adjuster seat and sleeve assembly 22 slotted end out into the poppet hole in one end of rack piston Do not use the spacer with the new poppetdesign You mustinstall the spacer with the old poppet design Install remaining poppetcompo 9 From the other end of the poppet hole in the rack nents piston install one poppet 23A poppet spring 24 push tube 26 other poppet 23A and the other new poppet adjuster seat and sleeve assembly 22 The new components will stack up as shown below J 36452 A Lbf ft Torque wrench Torque both poppet seat and sleeve assemblies to 18 Ibfeft 25 N em Return to step 27 page 43 Valve Housing W orm Screw Disassembly Tools Required Materials Required Hammer Lbf ft Torque wrench Punch center Punch roll pin Lbf en Torque wrench J 37464 J 37070 J 37073 Screwdriver Small probe or pick Sockets 12 point sockets Place valve housing and valve a
45. g 11 O ring Valve Housing High Temp 12 Thrust Washer Thick 15 Thrust Bearing 2 16 Thrust Washer Thin 17 Bearing Adjuster 18 Adjuster Locknut 27 Balls 29 Seal Cap 30 Ball Return Guide Cap 31 Torx Screws 2 Cap Strap 32 Ball Return Guide Strap 35 Grease Fitting 43 Adjusting Screw Sector Shaft 44 Retainer Adjusting Screw 47 jam Nut 49 Vent Plug Side Cover 50 Bleed Screw Manual 51 Plug Auto Bleed 52A Fixed stop screw 54 Auxiliary Port Plug 2 55 O ring 2 Aux Port Plug 57 O ring Relief Valve 59 Service Poppet Adjusting Screw 60 Service Sealing J am Nut Parts Vary by Gear Size Item Description Seal Ring Valve Housing Teflon Seal Ring O ring Back up Rack Piston Poppet Seat and Sleeve Assy 2 Poppet 2 old design Poppet 2 new design Poppet Spring Spacer Rod Push Tube Ball Return Guide Halves 2 R H ER Retaining Ring 2 Roller Bearing Dirt Seal Dirt and Water Seal Trunnion Washer Spacer Seal 2 Output Gasket Side Cover Special Bolts 6 or 8 Side Cover Part Number 020251 478044 478060 478050 401637 478076 032823 029123 032200 158 029116 032200 152 400143 070027 400144 400149 027007 213684 X1 478042 400161 020228 400167 037032 021200 062005 025150 036201 213705 021397 021426 415437 Al 032229 032200 153 021407 025119 TAS40 032829 032828 032827 409118 A2 040210 040248 401662 040209 080154 400158 4
46. he dimensional characteristics TAS40 55 65 Inspect side cover 46 DU bushing for damage Also check side cover bushing to sector shaft clearance If damage exists or if clearance exceeds 008 0 20 mm replace side cover bushing assembly TAS85 Inspect roller bearing in side cover assembly 46 for brinelling or spalling If either condition exists replace the side cover and bearing assembly Inspect the sector shaft 42 bearing and sealing areas and sector teeth contact surfaces for brinelling spalling or cracks Run your fingemail edge across these areas to detect steps Remove masking tape from the shaft and inspect for twisted or otherwise damaged serrations If any of these conditions exist replace the sector shaft A service sector shaft will come assembled with the adjusting screw 43 and retainer 44 Assembly Preparation Wash all parts in clean OSHA approved solvent Air blow dry them only Because they are flammable be extremely careful when using any solvents Even a small explosion or fire could cause injury or death W ear eye protection and be sure to comply with OSHA or other maximum air pressure requirements Replace all seals seal rings and gaskets with new ones each time you disassemble the gear TRW Commercial Steering Division makes complete seal kits available These parts can be purchased through most OEM parts distributors Contact your local dealer for availability Assembly To
47. heel in the opposite direction end of timing mark on the master gear away from adjusting screw until the other axle stop is contacted b Pull hard on the steering wheel put 40 Ibs rim pull on a 20 dia steering wheel c Release the steering wheel and shut off the engine 9 Loosen the sealing nut and back out the adjusting screw on the master gear until 1 is past the nut Tighten the sealing nut against the housing Do not hold the steering wheel at full turn for more than 10 seconds ata time the heat build up at pump relief pressure may damage components 10 a Start the engine and let it idle b Turn the steering wheel in the original direction end of timing mark on the gears toward adjusting screw until axle stop contact is made c Hold the steering wheel in this position with 40 lbs rim pull for 10 seconds then release Repeat this hold and release process as many times as necessary while completing steps 11 amp 12 11 12 15 14 a With steering wheel held at full turn loosen the 15 jam nut on the master gear and hold it in place with a wrench b Turn the adjusting screw in clockwise using finger pressure only don t use a ratchet until the Allen wrench comes to a stop Do not attempt to tum it in farther Pause the turning in process each time the driver releases the steering wheel Continue tuming only while the wheel is held at full tum c Back off the adjusting s
48. in TAS unit e Connect steering column to input shaft torque pinch bolt to vehicle manufacturer s recommendation e Install pitman arm on output shaft torque bolt to vehicle manufacturer s recom mendation Initial Poppet Setting For this procedure to work correctly you must have A new gear received from TRW or your vehicle manufacturer s aftermarket system or a used gear on which poppet seats have been replaced or reset during gear disassembly procedures ALSO A fixed stop screw installed in the housing or a poppet adjusting screw installed so that it dupli cates the fixed stop screw length Full turn in one 1 direction Full turn in other 2 direction The axle stops and all steering linkage must be set according to vehicle manufacturer s specifications and the pitman arm must be correctly aligned on the sector shaft for poppets to be set correctly With the engine at idle and the vehicle unloaded tum the steering wheel to full travel in one direction until axle stop contact is made Maximum input torque to be applied during this procedure is 40 Ib rim pull 178 N on a 20 in 508mm diameter steering wheel If you encounter excess rim pull effort allow the vehicle to roll forward or jack up the vehicle at the front axle Follow the same procedure while tuming the steering wheel in the other direction The poppets are now positioned to trip and reduce pressure as the steered wheels approach the axle
49. iston seal is on the end of the rack piston farthest from the input shaft Remove the seal before removing the valve housing assembly to prevent the Teflon rack piston seal ring 20 from hanging up when it exits the housing Expose the seal through the sector shaft cavity then cut and remove the seal ring from the rack piston Remove and discard the valve housing seal rings 6 amp 7 Do not remove the input shaft valve worm assembly or balls from the rack piston until the ball return guides are removed as damage to the ball guides will occur Remove and discard the two special sealing screws 31 Remove the ball return cap 30 and seal 29 or strap 32 discard the seal OR Bend down the two tabs tangs that are against the hex head bolts Remove two bolts and the clip Discard the clip Make sure the rack piston is on a cloth so the steel balls that fall out won t roll very far Remove ball retum guide halves 28 by carefully inserting a screwdriver between the rack piston and guides Left hand ball return guide halves are copper plated for identification and right hand guides are not plated Retain the guides for reassembly Remove steel balls 23 Remove the steel balls 27 from the rack piston 19 by rotating the input shaft valve worm assembly until the balls fall out Place the balls and retum guides in a cup or other container Count the balls and make sure all have been removed The s
50. low is Input shaft Output shaft lash and the solution is to make a sector shaft adjustment You would then proceed to section 3 of this Service Manual and perform the Sector Shaft Adjustment procedure Thermometer Reservoir Filter Power Steering dy System Analyzer Failed Test Problem Solution Section Test 8 Excessive Internal Leakage Replace damaged parts reseal 4 Test 9 Excessive Internal Leakage Replace damaged parts reseal 4 Test 11 Intermittent loss of power assist Reseal 4 Test 12 Air in hydraulic system Bleed system 3 Test 17 Poppets improperly set Reset poppets 3 Test 18 Input shaft Output shaft lash Adjust sector shaft 3 Test 19 Steering gear misadjusted Adjust sector shaft first 3 if required replace worm assembly 4 Test 28 Gear control valve imbalanced Replace worm valve assy reseal 4 External Leakage Porosity in housing side cover or valve assy Replace porous parts reseal 4 Input shaft seal Replace seal 3 Output shaft seal Reseal 4 Side cover seal vent plug bolts gaskets Replace parts reseal 4 Valve housing sealing area Remove nicks or replace reseal 4 Poppet screw or sealing nut Replace with poppet adjusting screw kit Reset poppets UJ Introduction This new TAS Service Manual replaces all previous editions of TRW s TAS40 55 65 and TAS85 Service Manuals Changes in the layout of this Service Manual reflect TRW s commitment to provide easily usable material and highly recogniza
51. m Poppet sleeve assembly 16 20 Ibf sft 22 27 Nem Poppet sealing nut service 33 37 Ibf sft 45 50 Nem Poppet fixed stop screw 38 42 lbfeft 52 57 Nem Poppet fixed stop screw 38 58 Ibf dt 52 79 Nem Relief valve cap 25 35 Ibf sft 34 48 Nem Sector shaft adjusting screw jam nut 40 45 Ibf sft 54 61 Nem Side cover bolts TAS40 108 128 Ibf t 147 174 Nem Side cover bolts TAS55 65 85 160 180 Ibf dt 217 244 Nem Valve housing bolts TAS40 55 65 75 85 lbf dt 102 115 N Mm Valve housing bolts TAS85 108 128 lbf dt 147 174 Nem tem numbers referenced are shown on the exploded Special tools can be purchased through views pages 13 and 15 SPX Corporation Kent M oore Tool Group After tightening to this torque value the adjuster must 28635 Mound Road be backed off 1 4 to 1 2 of atum as described in step 22 Warren MI 48092 on page 61 1 800 328 6657 Torque value indicated is using recommended tools TAS Series Exploded View Standard TAS85 Construction Retaining Ring 2 Roller Bearing Dirt Seal Dirt and Water Seal Trunnion Washer Spacer Seal 2 Output M Sector Shaft Item Description 16 Thrust Washer Thin 43 Adjusting Screw Sector Shaft 1 Bolts 4 Valve Housing 17 Bearing Adjuster 44 Retainer Adjusting Screw 2 Dirt and Water Seal 13 16 Serr 18 Adjuster Locknut 45 Gasket Side Cover 2B Dirt and Water Seal 7 8 Serr 19 Rack Piston 46 Side Cover Assembly 2C Dirt and Water Se
52. mp water seal and install it over the input shaft Seat it in the groove behind the serrations and against the valve housing Reconnectcolumn 15 Reconnect the steering column to the input shaft and tighten the pinch bolt to torque level specified Reconnect return 16 Reconnect the retum line to the steering gear retum line port Air bleed system 17 Air bleed the system using the procedure on page 21 Seal PartNo Serration Size Major Serration Dia 478044 13 16 x 36 0 807 0 799 478060 7 8 x 36 0 866 0 857 478050 1 x 36 0 987 0 977 478050 1 x 79 1 008 1 000 Sector Shaft Adjustment Tools Required Materials Required This adjustment can only be completed on the vehicle if the adjusting screw jam nut is accessible This nut is located on the side cover Screwdriver Va Socket 3 Photos in this section were taken on a mock frame rail for 4 Open end wrench clarity Center the sector 1 With the engine on rotate the steering wheel input shaft shaft until the timing mark on the sector shaft lines up with the mark on the housing The line on the sector shaft should be at a 90 angle from the input shaft The sector shaft is now on its center of travel Tum the vehicle off Remove the drag 2 _ Remove the drag link from the pitman arm link To avoid resetting the poppets do not rotate the input shaft more than 1 turns from the center of travel position while the drag link is disconne
53. mperature industrial grease Exxon Unirex RS460 Apply more of the grease to the inside of a new dirt and water seal 2 2B or 2C and install it over the input shaft Seat the Seal in the groove behind the serrations and against the valve housing Return to step 28 page 44 Trademark of Exxon Oil Corp Roller Bearing or Ret Ring Repl Standard Tools Required Materials Required Press Screwdriver J 37071 TAS55 65 or J 37071 A TAS55 65 J 37705 TAS40 J 38779 TAS85 Remove roller 1 Standard Gears Only If roller bearing 37 in housing bearing if required needs to be replaced place the bearing removal end long end of the bearing and seal tool against the Side cover end of the bearing and press it out of trunnion end of the bearing bore Discard bearing Remove retaining 2 Standard Gears Only If the retaining ring 36 that is ring still in the housing bearing bore needs to be re placed remove it through the trunnion end of the Sewanee bearing bore to protect the pressure seal bore area from being damaged Install retaining 3 Standard Gears Only Insert retaining ring 36 if it ring was removed into the housing bore from the trunnion end to protect sealing area Make sure it 2 4 is seated in the retaining ring groove closest to side cover end of the bearing bore Lubricate the bearing bore Press in housing 4 Standard Gears Only Press the roller bearing 37 into roller
54. ols Required Materials Required 22 Allen J 37071 TAS55 65 Ratchet ATF oll Seal kit Ross TAS400003 wrench or Screwdriver Grease Exxon TAS550004 Loft Torque J 37071 A Sockets Unirex RS460 TAS650012 wrench J 38779 TAS85 Torx sockets Masking tape TAS850003 or 4 Hammer Press Vise Yio 14 x 71 4 All Thread J 37705 TAS40 Punch Install dirt seal 1 Standard Gears Install new dirt seal 38 into the trunnion end of the housing sector shaft bore and against the bearing with the seal lip out Install retaining 2 Standard gears only Install the outside retaining ring ring 36 seating it firmly in the housing retaining ring groove Trademark of Exxon Oil Corp Install washer Press seal into housing J 37705 TAS4O 37071 or J 37071 A TAS55 65 J 38779 TAS85 Press Grease the bearing and seal area Grease Install dirt amp water seal 37071 or J 37071 A Press Assemble seal rings 3 4 1 Standard gears only Install washer 40 into the side cover side of the housing seal bore with the small diameter piloted into the retaining ring If you are working with a housing with an unmachined trunnion face you may need to square the hous ing to the press with shims for step 4 All gears Assemble new seal 41 onto bearing and seal tool short end so the lip with the garter spring is toward the shoulder of the tool Working from the side co
55. p cavity Tum the relief valve cap as as sembled into the valve housing and torque to 30 Ibfeft 41 Nem TAS40 55 65 Lightly oil DU bushing Do not grease TAS85 only Apply a generous amount of Exxon Unirex RS460 do not substitute another type of grease to the caged bearing assembly inside the side cover This bearing Is sealed and will receive no lubrication from the hydraulic fluid in the gear Failure to use the proper grease could result in premature bearing wear Grease and assemble new seal 41 onto installation tool so the side with the garter spring is against the shoulder of the tool Pilot the tool into the side cover 46 with a force of 100 800 Ib 445 3560 N until it is seated against the bearing or bushing Make sure the OD of the seal and the ID of the bore are free from grease and dust for proper engagement of the seal TAS 40 55 65 Lightly oil short bearing area of sector Shaft Do not grease TAS85 only Apply a generous amount of Exxon Unirex RS460 to the short bearing area of the sector shaft Insert the sector shaft 42 into the side cover subassembly 46 and screw the sector shaft adjusting screw 43 counterclockwise into the side cover until the screw reaches solid height Rotate the adjusting screw clockwise one half tum so the side cover will rotate freely on the sector shaft Trademark of Exxon Oil Corp Install jam nut 23 Install the sector shaft adjusting scr
56. ped Screwdriver Inspect roller 31 bearing Inspect housing 32 screws and plugs Standard gears only Remove the retaining ring 36 that is closest to the output end of the housing trunnion Standard gears Remove and discard dirt seal 38 Step bore gears Remove and discard the dirt and water seal 61 Standard gears Insert a screwdriver into the housing bearing bore from the trunnion end and carefully push the seal 41 and spacer washer 40 out of the other end of the bearing bore without damaging the sealing area of the bore Discard the seal Step Bore gears Remove the retaining ring 63 through the side cover opening Then insert a screwdriver through the trunnion opening and carefully push the seal 41 out without damaging the sealing area of the bore Discard the seal Standard gears Inspect roller bearing 37 in the housing for brinelling or spalling Inspect retaining ring for damage If replacement of either part is required go to Roller Bearing or Retaining Ring Replacement on page 64 If not proceed to step 32 Step Bore gears Inspect the roller bearing 37 for brinelling or spalling If replacement is required go to Roller Bearing Replacement Step Bore on page 65 If not proceed to step 32 Inspect the following for damage ePoppet fixed stop screw 52 or 52A and washer 53 if equipped ePoppet adjusting screw 59 and sealing nut 60 eAuto bleed plug 51 eM anual
57. rack piston and sector shaft teeth for final adjustments Loosen adjusting 3 Tum sector shaft adjusting screw 43 counterclock 7 screw and note wise one half tum and note maximum torque required T s _ Em tordue to rotate the input shaft valve worm assembly sa J 4 through one half turn 180 each side of center Lbfein Torque wrench Screwdriver 1 16 Socket Adjust adjusting screw 3 4 Socket 11 46 Socket Lbf dt Torque wrench Lof dn Torque wrench 4 Adjust sector shaft adjusting screw 43 clockwise to increase maximum torque noted in step 3 by 7 Ibfein 8 Nem Tighten jam nut 47 firmly against side cover while holding the adjusting screw in position Final torque jam nut to 43 Ibfeft 58 Nem and check input shaft valve worm assembly torque again Readjust if input shaft torque exceeds 40 Ibf en 4 5 Nem Section 5 Reinstallation Reinstallation sesse ee GE DE ER ae IE Ger REG 70 PODDCE Resetting iewe iN ke Ge N GE cts 70 Maintenance TIPS ie ee ee EE ee EE RR RE ER ee EE Re ee EE Ee ee EE 71 GIOS AA ER RE EE EER N 72 Reinstallation Verify that axle stops are set to manufacturer s wheelcut or clearance Specifications Bolt gear to frame torque to vehicle manufacturer s recommendation Connect return line to reservoir in TAS retum port Connect hydraulic line from pump to pressure port in TAS unit Connect steering column to input shaft torque pinch bolt
58. rd the adjust ing screw just installed Turn in this direction until axle stop contact is made d Pull hard on the steering wheel put up to 40 Ib nim pull on a 20 dia steering wheel after the axle stop is contacted Set upper poppet 8 a Tum the steering wheel in the opposite direction end of timing mark away from adjusting screw until the other axle stop is contacted b Pull hard on the steering wheel put up to 40 Ib nim pull on a 20 dia steering wheel c Release the steering wheel and shut off the engine Back outadjusting 9 Loosen the sealing nut and back out the adjusting screw screw until L is past the nut Tighten the sealing nut against the housing 732 Allen wrench Do not hold the steering wheel at 3 4 Open end full turn for more than 10 seconds wrench ata time the heat build up at pump relief pressure may damage components Set lower poppet 10 a Start the engine and let it idle b Tum the steering wheel in the original direction end of timing mark toward adjusting screw until axle stop contact is made c Hold the steering wheel in this position with up to 40 Ib rim pull for 10 seconds then release Repeat this hold and release process as many times as necessary while completing step 11 Position adjusting 11 a With steering wheel held tightly at full tum loosen screw the jam nut and hold it in place with a wrench b Tum the adjusting screw in clockwise u
59. rer RW Automotive Commercial Steering Systems TAS Steering Gear Service M anual TAS 40 55 65 AND 85 SERIES STANDARD STEP BORE Design Features Q o Rotary Valve This device provides responsive steering control Poppets optional These unloading valves are automatically set to furnish power steering pump protection and reduce pressure to unload steering linkage at vehicle axle stop settings Recirculating Balls Combine high mechanical efficiency with smooth operation Dirt amp Water Seals Lip type seals on both input and output shafts Torsion Bar Provides positive valve centering with definitive feel of the road Relief valves fumish pump protection by limiting maximum pressure optional Balanced area cylinder so back pressures cannot affect steering stability High temperature seals were developed to with stand temperatures of 250 F M anual steering capability provides for steering control in the event of hydraulic failure Auxiliary porting available for auxiliary cylinder control Seal protectors provide protection from harsh environment conditions Hazard Warning Definitions A warning describes hazards or unsafe practices which could result in severe personal injury or death A caution describes hazards or unsafe practices which could result in personal injury or product or property damage NOTE A note gives key information to make following a procedure e
60. s flow in internal cavities Scoring Scratch Shock Load Shake or jar Spalling Flaking or chipping Subassembly An assembled unit that fits into a larger unit Supply Line Line that connects pump to steering gear Tw isted Serrations Output shaft serrations damaged by impact overload Serrations can be twisted at the area between the large diameter of the shaft and the end of the serrations TRW Automotive Commercial Steering Systems 800 Heath Street Lafayette IN 47904 Tel 765 423 5377 Fax 765 429 1868 htto www trw com commercialsteering TRW Inc 2000 TRW 1108 Rev 3 00
61. seeeeeseees 21 Input Shaft Seal Replacement cccceeeceecsssseeeseesseeesseeeeeseseees 22 Sector Shaft A deSUKENE es Ad NS AE EO Ee eb oe Ee gr 26 Poppet Readjustment 119 8 KE ME EE N EE N EN N 28 BI Goa sasa E A intact 31 Reseal amp Repair BEES jle AE AE OR OR E 37 MODE OI EE EE EE ER EE 45 PSST AO a OE AE OE AE 47 Intemal Damage Repair by reference Poppet Component Replacement 2iiiiaasssss s raar 55 Valve Housing Worm Screw Disassembly aa aina aaiiraiii 57 Roller Bearing or Retaining Ring Replacement 64 Roller Bearing Replacement Step Bore Ge r 65 Replace Housing Ports Plugs Screws Fittings 66 Final Adjustments us RE EI ER GE Ge N ai Gie NG 67 Reinstallation Me gees l a l I a a 70 Poppet Resetting iinazasanaaas saaaaa aasnannannannaannnnnnnnnnnnnnannannannan 70 Maintenance HOS as EE IG De ee oe ie ee EE ie 71 212323 AR AO N EE OE ON 72 All steering mechanisms are safety critical items As such itis imperative that the instructions in this booklet be follow ed to the letter Failure to observe the procedures set forth in this pamphlet may result in a loss of steering Section 1 General Information Directory for Chart Your Way to Easy Steering Users 6 ME OUI ON AA E 7 Oil Flow Illustration AE EE 8 General Design iaaaaaaaaaasaaa aaa annanaananannannannnaanannannnnaan 9 General Op
62. sing 7 32 Allen finger pressure only don t use a ratchet until the wrench Allen wrench stops Do not attempt to tum it in 3 4 Open end further Pause the turning in process each time wrench the driver releases the steering wheel continue 3 4 Socket turning only while the wheel is held at full tum Lbf sft Torque c Back off the adjusting screw 34 turns and tighten wrench the sealing nut Torque sealing nut to 35 Ibf ft The procedure is 12 The poppets have now been completely reset complete Lower the vehicle Check the reservoir and fill if required The length of the adjusting screw beyond the nut must be no more than 1 s for proper thread engagement The length of adjusting screw beyond the sealing nut may be different for each vehicle Poppet Readjustment Dual Gears Mirror Image Systems and Reversed Image Systems Before setting poppets on a dual gear system you must determine whether the system has mirror image gears or reversed image gears The procedures are slightly different for each type of system 1 Park the vehicle with the wheels turned all the way to the axle stop in either direction Turn the vehicle off 2 Look at the output shaft timing mark nearest the housing piston bore on the master gear Is this mark pointing toward the poppet screw or away from it 3 Now check the same timing mark on the rotary cylinder Does it point toward the poppet screw or away from it If they point to
63. ssembly in vise Unstake adjuster locknut Roll pin punch Hammer Remove bearing adjuster locknut J 37464 Remove bearing adjuster J 37070 4 With wom vertical place the valve housing input Shaft valve worm assembly in a vise Unstake the valve housing 5 where it was upset into the adjuster locknut 18 slot Also unstake adjuster nut from adjuster 17 Tum bearing adjuster locknut 18 out of the valve housing Tum bearing adjuster 17 out of the valve housing Remove seal ring and o ring Small probe or pick Remove input shaft Remove thin washer and bearing Remove thick washer and bearing Remove bearing components 5 6 7 SA Remove and discard seal ring 8 and o ring 9 from bearing adjuster Remove the input shaft valve worm assembly 13 or 13A from the valve housing Remove thin thrust washer 16 and thrust bearing 15 from input shaft Remove thick thrust washer 12 and thrust bearing 15 from valve housing Input shaft valve worm assembly must not be disassembled further The components were a select fit at assembly and are available only as part of this subassembly If disas sembled further the subassembly must be replaced OR For alternate construction TAS65 gears remove Spacer sleeve 14 thin washer 16 thrust bearing 15 and thick washer 12 If the TAS65 gear has a ball bearing and ball race in the valve housing remov
64. teel balls are a matched set If any are lost the set must be replaced by service balls Number of factory balls installed TAS40 29 TAS55 31 30 if date code is 337 89 or earlier TAS 65 32 TAS 85 34 Separate rack 24 Remove the input shaft valve worm valve housing piston from worm Subassembly from the rack piston subassembly Remove seal ring 25 Cut and remove the Teflon seal ring 20 and o ring and o ring 21 from the rack piston if not removed during disassembly step 19A Pocket knife Inspect poppet 26 Push poppet stems they should spring back Push assemblies poppet seat it should not move by hand If compo nents are bent or broken poppet stems don t spring back or poppet seat moves by hand go to Poppet Component Replacement section on page 55 Other wise proceed to step 27 TRW recommends the poppet adjuster seat and sleeve assem blies 22 not be removed unless replacement of poppet components is required P Inspectvalve 27 Inspect valve housing worm screw subassembly for FA housing and worm heat damage or bearing roughness If these condi TF screw tions are present or if there was excessive intemal leakage or if preload adjustment is required go to Valve Housing W orm Screw Disassembly procedures on page 57 If not proceed to step 28 Remove retaining 28 ring if equipped Remove dirt seal 29 Screwdriver Remove pressure 30 seal and spacer washer if eduip
65. th two unloading valves one at each end of the rack piston One valve or the other depending on the direction of tum will trip as the steered wheels approach the axle stops which must be set according to manufacturer s specification The tripped valve reduces pressure in the gear and helps to reduce heat generated by the pump At the same time the valves also reduce forces on the steering linkage These valves are automatically set to axle stops after installation in vehicle at first full right and left turn Relief Valve Some TAS gears with or without poppets are supplied with a relief valve The relief valve limits maximum Supply pressure to protect the power steering gear but it does not reduce pressure as the steered wheels ap proach the axle stops Bleed Systems Some TAS gears which are mounted with the output Shaft above the rack piston bore are equipped with either an automatic bleed system or a manual bleed screw The procedure for air bleeding the system Is on page 21 of this manual Replacement of damaged automatic bleed plugs and manual bleed screws is described on page 66 Approved Hydraulic Fluids Automatic Transmission Fluid Dexron II Mobil ATF 210 Automatic Transmission Fluid Type E or F M obil Super 10W 40 Motor Oil Chevron 10W 40 Premium Blue 2000 SAE 15W 40 Chevron Custom 10W 40 Motor Oil Shell Rotella T30W Chevron Torque 5 Fluid Shell Rotella T SAE 30 Exxon Nuto H32 Hydraulic Fluid Texaco 10W
66. this could disrupt the poppet setting achieved at initial installation The steering gear is in the straight ahead position when the timing marks on the end of the housing trunnion and sector shaft are aligned Remove the supply and return lines from the gear and immediately plug all port holes and fluid lines TAS steering gears can weigh up to 110 pounds dry Exercise caution when you remove lift carry or fix in a bench vise Remove the steering gear from the vehicle and take it to a clean work surface Clean and dry the gear before you start to disassemble it As you disassemble the gear clean all parts in clean OSHA approved solvent and air blow dry them only Because they are flammable be extremely careful when using any solvents Even a small explosion or fire could cause injury or death Wear eye protection and be sure to comply with OSHA or other maximum air pressure requirements Never steam clean or high pressure wash hydraulic steering components Do not force or abuse closely fitted parts Use care that bearing and sealing surfaces are not damaged by the assembly and disassembly procedures Keep each part separate to avoid nicks and burrs Discard all seals o rings and gaskets removed from the gear Replace them with new parts only The steering gear should be identified to the vehicle from which it was removed The poppet adjuster seat and sleeve assemblies are set for that particular vehicle onl
67. to hold seal in groove while assembling Be sure not to trap the seal outside of the groove during reassembly Assemble ball 14 If your gear was equipped with the ball return guide i return guide strap strap 32 or if it was equipped with the clip install i the new ball return guide strap Position it on the 539 Allen or T rack piston install two new Allen or Torx head 30 Torx socket screws 31 and torque each screw altemately until Lbfein Torque a final torque of 18 Ibfeft 24 5 Nem is achieved wrench Grease Rotate input shaft 15 Rotate the input shaft from one end of travel to the to check for proper other without contacting the poppet stem to the installation of valve housing and without moving the valve hous balls ing face more than 2 2 69 1 mm from input end upper end of rack piston If you cannot rotate the input shaft remove the balls and reassemble them If you install a gear on a vehicle with the w orm shaft unable to rotate the gear will not function correctly Steering and gear failure may result Install rack piston 16 Apply clean oil to Teflon seal ring 20 on rack piston worm valve Make sure there is a space of 38 1 2 10 0 13 0 mm assembly between valve housing 5 and poppet stem to prevent poppet contact at either end Remove the All Threads and push the rack piston assembly into the housing with the rack piston teeth toward the sector shaft cavity Line up the valve ho
68. u install them Do not allow the Teflon seal ring to be twisted Apply clean oil to housing cylinder bore Place the rack piston 19 in the housing piston bore with ball return guide holes up Insert the worm screw into the rack piston close to maximum depth without the valve housing making contact with the poppet stem Insert two 614 All threads through valve housing bolt holes and tighten into housing to support the worm screw Line up rack piston ball guide holes with the worm ball track grooves by rotating the input shaft Assemble the ball retum guide halves 28 into the rack piston until seated rotate the input shaft Slightly if necessary Do not seat guides with a hammer Damage to guides can resultin subsequent lockup or loss of steering If a new rack piston 19 or a new input shaft valve worm subassem bly 13 or 13A is being assembled the balls 27 removed from the unit must be discarded and a service ball kit utilized The balls in a service ball kit are sized to function in the ball track guide path as altered by component replacement When using the service ball kit use the correct quantity of service balls TAS 40 29 TAS55 31 TAS 65 32 TAS 85 34 Assemble balls 12 Hold the ball return guides 28 firmly in place during this entire procedure Insert as many of the steel balls as you can through the hole in the top of the ball retum guides Rotate the input shaft to pull the balls down and around th
69. using cylinder feed hole with the gear housing feed hole M ake sure both o rings in the valve housing remain IN position Do not damage the seal ring 19 while installing the rack piston into housing If the seal ring end of rack piston enters the housing first the seal ring will be destroyed when the rack is removed The poppet seat and sleeve assemblies 22 must not bottom against the internal poppet stops in the steering gear until the gear is installed on the vehicle and the poppet adjustment procedures are performed Install valve 17 Lubricate and install the four valve housing bolts 1 housing bolts into the housing Torque the TAS40 55 and 65 bolts alternately to 80 Ibfeft 108 5 Nem Torque TAS85 bolts E 16 Torx to 118 Ibfeft 160 N em socket TAS4O 55 65 E 18 Torx socket TAS85 Lbfdt Torque wrench Install relief valve 18 parts Ve Socket Lbf ft Torque wrench Lubricate side 19 cover bushing bearing Press seal in side 20 cover J 37705 TAS40 37071 or J 37071 A TAS55 65 J 38779 TAS85 Press Lubricate sector 21 shaft Install sector shaft 22 into side cover a Boemer If the gear is equipped with a relief valve assemble a new o ring 57 on relief valve cap 56 Assemble the small end of tapered spring onto the pin on the relief valve cartridge and insert the assembly 58 large end of tapered spring end first into the relief valve ca
70. using Ports Plugs Screws Fittings Tools Required Materials Required Allen wrench Torx sockets Sockets Lbfein Torque wrench Lof et Torque wrench Replace poppet fixed stop screw Va Socket or E 14 Torx socket lof ft Torque wrench Replace poppet adjusting screw 72 Allen wrench 3 4 Or 78 closed end wrench Lbf ft Torque wrench Replace automatic bleed screw and aux port plugs E 14 Torx socket Lbf ft Torque wrench Replace manual bleed screw is Hex socket Lof dn Torque wrench If damaged remove and replace the poppet fixed stop screw 52 or 52A and washer 53 if equipped Replace with poppet fixed stop screw 52A discard the washer Torque to 48 Ibfeft 65 Nem If damaged remove poppet adjusting screw 59 and sealing nut 60 without allowing the nut to change its position on the screw Assemble the new nut onto the new adjusting screw Matching its position to the nut and screw removed Torque sealing nut to 35 Ibfeft 47 N em If damaged remove and replace automatic bleed plug 51 Torque to 48 Ibfeft 65 Nem If damaged remove and replace permanent auxiliary port plugs 54 and o rings 55 Assemble new o rings 55 on port plugs and torque to their respec tive ports in the housing or valve housing to 30 Ibfeft 41 N em If damaged remove and replace manual bleed screw 50 Torque to 45 Ibfein 3 4 Nem Return to inspection section p
71. ust be no more than 1 for proper thread engagement NOTE The length of adjusting screw beyond the sealing nut may be different for each vehicle Poppet Readjustment Dual Gears Reversed Image Tools Required Materials Required 732 Allen wrench 8 Open end wrench 4 Open end wrench 3 4 Socket Lbf eb Torque wrench Hydraulic fluid J ack 1 Set the axle stops to vehicle manufacturer s wheelcut or clearance specifications Start the engine and allow the vehicle to idle for 5 10 minutes to warm the hydraulic fluid Shut off the engine 2 If new poppet adjusting screws and nuts are being used tum the screws into the non sealing end of the jam nuts until the drive end of screw is flush with the nut Your steering gear and rotary cylinder will have either fixed stop bolts or adjusting screws If the adjusting screw is already part of the steering gear or cylinder back the nut off of the adjusting screw until it is flush with the end of the adjusting screw 3 Make sure the engine is off and the road wheels are in straight ahead position Remove and discard the poppet fixed stop bolts if equipped and washers if equipped from the lower end of housing on both the master gear and the rotary cylinder If the unit has poppet adjusting screws and Sealing nuts that need to be replaced remove and discard them 4 Tum the adjusting screws and sealing nut assem blies without rotating the nut on th
72. vehicle is developing excessively high hydraulic fluid temperatures consult with your vehicle manufacturer for recommendations Maintain grease pack behind the output shaft dirt and water seal as a general maintenance procedure at least twice a year in the Spring and Fall Grease fitting is provided in housing trunnion Use only NLGI grade 2 multipurpose chassis lube and use only a hand operated grease gun on fitting Add grease until it begins to extrude past the sector shaft dirt and water seal Standard Gear Corrosion Inhibiting Grease Barrier N A 7 1 NEE N EP Bearing High Pressure Output Seal ater Seals Section 3 On Vehicle Service Filling and Air Bleeding the System ccsssseeeseseeeseeees 21 Input Shaft Seal Replacement ccccssseeessssereeeseeeeeeees 22 Sector Shaft Adjustment ee ee ee RR RE EE ee EE Ee 26 Poppet Readjustment SINGS Gee ins ERGE EE ODE 28 Didi Ee lis ie EE ER ee EG ee ad ee 31 J Filling and Air Bleeding the System Tools Required Materials Required 56 Socket Hydraulic fluid Lof sn Torque wrench Make sure poppets are set correctly before beginning this Run engine for 10 1 Fill the reservoir nearly full Do not steer Start and seconds turn off run the engine for 10 seconds then shut it off and fill reservoir Check and refill the reservoir Repeat at least three times checking the reservoir each time Hydraulic fluid Do not
73. ver side of the housing pilot the seal tool into the washer and bearing and press with a force of 100 800 ID 445 3 560 N until the seal is seated firmly Step Bore gears only Install the inside retaining ring 63 from the side cover opening Seat the ring firmly in the retaining ring groove Standard gears Liberally pack the area between dirt Seal 38 and pressure seal 41 including roller bearing with clean high temperature industrial grease 045422 Exxon Unirex RS460 Step Bore gears Install the dirt amp water seal 61 with the bearing and seal tool long end making Sure it is not cocked Press the seal only until it Seats against the bearing don t push it in farther Liberally pack the roller bearing and new seals with clean high temperature industrial grease Exxon Unirex RS460 Lightly oil new seal ring 7 and assemble in valve housing mounting face groove TAS 40 55 65 Oil new Seal ring 6 and assemble in valve housing mounting face groove TAS85 Oil new seal ring 6 and assemble in valve housing pilot groove Trademark of Exxon Oil Corp Install rack piston 8 o ring and seal ring Position rack 9 piston in housing Insert worm and 10 valve assembly into rack piston 1 16 14 x 71 4 All Thread Assemble ball 11 return guide halves Install a new backup o ring 21 and then a new Teflon seal ring 20 on rack piston 19 Do not over stretch these rings as yo
74. wo poppets 23 or 23A spring 24 components and push tube 26 Some gears will also have a Spacer rod 25 to be removed i Old Design New Design rin ring OO MNNNNNd0000dd ddd ddd Poppet Poppet Poppet Poppet E J Spacer Rod i i O _ PoppetSeat OL o Poppet Seat Ik Poppet Seat and Poppet Seat and aed Push Tube Sleeve Assembly Push Tube Sleeve Assembly Remove other seat 5 Remove and discard remaining poppet seat and amp sleeve if sleeve assembly only if reduired necessary It is possible to reset one poppet adjuster seat and sleeve assembly for automatic poppet adjustment while it is in the rack piston if one adjuster seat and sleeve assembly and the poppets spring spacer rod and push tube are removed Reset remaining 6 If one poppet seat and sleeve assy 22 was left in poppet seat and rack piston it can be reset for automatic poppet sleeve assembly adjustment by inserting a 3 9 52 mm diameter X 6 152 4 mm drill rod down through the poppet seat hole at the opposite end of the rack piston and against the adjuster seat to press the seat in until it bottoms against the adjuster sleeve Press 3 2 X 6 Dnill rod Apply Locquic T 7 Carefully apply Locquic T primer to the threads in primer and Loctite poppet holes and threads on the new seat and RC680 Sleeve assemblies 22 Allow to dry for ten min utes then care
75. y Disassembly Tools Reduired Materials Required Allen wrenches Screwdriver Emery cloth Pocket knife Sockets Masking tape Ratchet eStandard Rolling head eTor pry bar Vise Rubber mallet Position gear in 1 Put the steering gear in a vise clamping firmly vise against the housing mounting flange or boss Input Shaft should be horizontal side cover and valve housing are accessible for disassembly Do not clamp against body of housing If mounting boss or flange is not accessible fabricate and attach a mounting plate to the housing mounting bosses Unplug ports 2 Prepare for fluid drainage and unplug hydraulic ports Appropriate size socket or open end wrench Position sector 3 _ Rotate the input shaft until the timing mark on the Shaft end of the sector shaft is in line with the timing mark on the end of the housing This will position the sector shaft for removal Remove dirt amp 4 Standard gears only Remove and discard dirt amp water seal water seal 39 from the housing trunnion Small screwdriver Clean sector shaft 5 Fine grade emery cloth Maskingtape Maskingtape tape Remove side cover 8 J bolts 1716 Socket or h Mie Socket Remove side cover 9 Soft mallet Tape sector shaft 6 Remove jam nut fe Remove any paint or corrosion from the exposed area of the sector shaft 42 Tape the serrations and bolt groove of the sector Sha
76. y Assemble bearing and thrust washer Assemble seals in bearing adjuster Assemble bearing s adjuster J 37070 Loft Torque wrench 18 19 20 21 22 Lightly oil and assemble new seal ring 8 onto input shaft and against the thick thrust washer 12 to hold the bearing components in place Dip the input end of the input shaft valve worm assembly 13 or 13A into oil up to the worm lead Assemble the input shaft end of the assembly into the valve housing 5 until it is firmly seated Apply oil and assemble the other thrust bearing 15 then the thin thrust washer 16 over the ball groove end of worm and seat them against the shoulder of input shaft valve worm assembly Lightly oil a new o ring 9 and assemble into the seal groove in bearing adjuster 17 Oil and work a new seal ring 8 into the same groove and smooth it out Be sure the valve housing adjuster locknut and bearing adjuster threads are clean and free of any staking burrs that would impede the locknut from turning freely on adjuster or the adjuster tuming freely in valve housing Lightly oil and assemble bearing adjuster 17 over worm and into valve housing Torque adjuster to 13 Ibfeft 18N em indicated torque using a torque wrench inserted in adjuster tool 4 37070 This will seat the components Back off adjuster Va to 1 2 of a turn Assemble new locknut 37464 Adjust to required input torque 3
77. y will damage the output seal 38 in housing causing the seal to leak Install side cover bolts 136 Socket TAS4AO 116 Socket TAS55 65 85 Lbf dt Torque wrench Remove tape Install dirt amp water seal Grease 28 29 30 Install TAS40 55 and 65 bolts in positions 3 and 4 first by hand For TAS85 Install in positions 3 and 6 first by hand Install the remaining special side cover bolts 48 into the side cover and tordue them in the sequence shown If bolts must be replaced use bolts of the same design type and length as those you removed Do not use a substitute Lubricate side cover bolts and torgue TAS40 bolts to 118 Ibfeft 160 Nem TAS55 65 and 85 bolts to 170 Ibfeft 230 N em Standard gears Remove tape from sector shaft and pack the end of the housing trunnion area at the sector shaft with clean high temperature industnal grease Exxon Unirex RS460 Apply more of the grease to the inside of the new trunnion dirt seal 39 and assemble it over the sector shaft and into the trunnion bore Step bore gears remove tape from the sector shaft Pack the end of the valve housing bore around the input shaft with clean high temperature industrial grease Exxon Unirex RS460 Apply more of the grease to the inside of anew dirt and water seal 2 2B or 2C and install it over the input shaft Seat the Seal in the groove behind the serrations and against the valve housing This st

TAS Steering Gear Service Manual

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