Overhaul

POWER STEERING GEAR AND LINKAGE


Disassembly and Assembly


COMPONENTS






CAUTION:
- Disassemble and assemble steering gear assembly by securing the mounting area in a vise using copper plates.
- Clean steering gear assembly with kerosene before disassembling. Be careful to avoid splashing or applying any kerosene over connector of discharge port or return port.

DISASSEMBLY
1. Remove fixing bolts of power steering solenoid valve, and then remove power steering solenoid valve from gear-sub assembly.
2. Remove cylinder tubes from gear housing assembly.
3. Remove rear cover cap from gear-sub assembly.





4. Measure adjusting screw height "H", and loosen adjusting screw.

CAUTION:
- Never loosen adjusting screw 2 turns or more.
- Replace steering gear assembly if adjusting screw is loosened 2 turns or more and it is removed.
5. Remove fixing bolts of gear-sub assembly, and then remove gear-sub assembly from gear housing assembly.
6. Remove O-ring from gear housing assembly.
7. Loosen outer socket lock nut, and remove outer socket.
8. Remove boot clamp, and then remove boot from inner socket.

CAUTION:
Never damage inner socket and gear housing assembly when removing boot. Inner socket and gear housing assembly must be replaced if inner socket and gear housing assembly are damaged because it may cause foreign material interfusion.
9. Remove inner socket from gear housing assembly.
10. Remove spacer from gear housing assembly.





11. Drill out the clinching part of gear housing assembly (end cover assembly side) outer rim with a 3 mm (0.12 in) drill bit. [Drill for approximately 1.5 mm (0.059 in) depth.]
12. Remove end cover assembly with a 36 mm (1.42 in) open head





(suitable tool).

CAUTION:
Never damage rack assembly surface when removing. Rack assembly must be replaced if damaged because it may cause fluid leakage.
13. Pull rack assembly together with rack oil seal (outer side) out from gear housing assembly.

CAUTION:
Never damage cylinder inner wall when removing rack assembly. Gear housing assembly must be replaced if damaged because it may cause fluid leakage.





14. Heat rack Teflon ring to approximately 40�C (104�F) with a dryer, and remove rack Teflon ring from rack assembly.

CAUTION:
Never damage rack assembly. Rack assembly must be replaced if damaged because it may cause fluid leakage.





15. Push rack oil seal inside with a 29 mm (1.14 in) socket and an extension bar to push out rack oil seal (inner side) from gear housing assembly.

CAUTION:
Never damage gear housing assembly and cylinder inner wall. Gear housing assembly must be replaced if damaged because it may cause fluid leakage.

INSPECTION AFTER DISASSEMBLY

Boot
Check boot for cracks, and replace it if a malfunction is detected.

Rack Assembly
Check rack for damage or wear, and replace it if a malfunction is detected.

Gear-Sub Assembly
- Check gear-sub assembly for damage or wear, and replace it if a malfunction is detected.
- Rotate gear-sub assembly and check for torque variation or rattle, and replace it if a malfunction is detected.

Gear Housing Assembly
Check gear housing assembly for damage and scratches (inner wall). Replace if there are.

Outer Socket and Inner Socket
1. Ball joint swinging torque





- Hook a spring balance at the point shown in the figure and pull the spring balance. Make sure that the spring balance reads the specified value when ball stud and inner socket start to move. Replace outer socket and steering gear assembly if they are outside the standard.

Standard for outer socket (Measuring point: Stud cotter pin mounting hole) Spring balance measurement : Refer to Specifications.

Standard for outer socket (Measuring point: "star" mark shown in the figure)
Spring balance measurement : Refer to Specifications.


2. Ball joint rotating torque





- Make sure that the reading is within the following specified range using the preload gauge [SST]. Replace outer socket if the reading is outside the specified value.

Standard
Outer socket rotating torque : Refer to Specifications.

3. Ball joint axial end play





- Apply an axial load of 490 N (50 kg, 111 lb) to ball stud using a dial gauge. Measure amount of stud movement, and then make sure that the value is within the following specified range. Replace outer socket and inner socket if the measured value is outside the standard.

Standard
Outer socket : Refer to Specifications.
inner socket : Refer to Specifications.


ASSEMBLY
1. Apply recommended fluid to rack Teflon ring.
2. Heat rack Teflon ring to approximately 40�C (104�F) with a dryer. Assemble it to mounting groove of rack assembly.

CAUTION:
Never reuse rack Teflon ring.





3. Install the Teflon ring correcting tool [SST: KV48104400 ( --
)] from tooth side of rack to fit rack Teflon ring on rack. Compress the ring with tool.





4. Apply recommended grease to rack oil seal, and then install rack oil seal in the following procedure. Then assemble rack assembly to gear housing assembly.

CAUTION:
- Install rack oil seal in a direction so that the lip of inner oil seal and the lip of outer oil seal face each other.





- Never damage retainer sliding surface by rack assembly.
Replace gear housing assembly if damaged.
- Never damage gear housing assembly inner wall by rack assembly. Gear housing assembly must be replaced if damaged because it may cause fluid leakage.





a. Wrap an OHP sheet [approximately 70 mm (2.76 in) � 100 mm
(3.94 in)]. Around rack assembly teeth to avoid damaging rack oil seal (inner). Install rack oil seal over sheet. Then, pull OHP sheet along with rack oil seal until they pass rack assembly teeth, and remove OHP sheet.





b. Insert rack oil seal (inner) into rack assembly piston (rack Teflon ring).
c. Push retainer to adjusting screw side by hand, and move the rack assembly inside the gear housing assembly so that the rack oil seal (inner) can be pressed against the gear housing assembly.
Wrap an OHP sheet [approximately 70 mm (2.76 in) � 100 mm d.





(3.94 in)]. Around the edge to avoid damaging rack oil seal
(outer). Install rack oil seal over sheet. Then, pull oil seal along with OHP sheet until they pass rack edge, and remove OHP sheet.
e. Install end cover assembly to rack edge, and move rack oil seal
(outer) until it contacts with gear housing assembly.





5. Tighten end cover assembly to specified torque using a 36 mm
(1.42 in) open head (suitable tool).

CAUTION:
Never damage rack assembly. Replace it if damaged because it may cause fluid leakage.





6. Crimp gear housing assembly at one point using a punch as shown in the figure so as to prevent end cover assembly from getting loose after tightening end cover assembly.
7. Apply recommended fluid to O-ring, and then install O-ring to gear housing assembly.
8. Install gear-sub assembly to gear housing assembly.
9. Install power steering solenoid valve to gear-sub assembly.
10. Install inner socket to gear housing assembly with the following procedure.
a. Install spacer to gear housing assembly.
b. Apply thread sealant into the thread of inner socket.
Use Genuine Medium Strength Thread Locking Sealant or equivalent. Refer to Recommended Chemical Products and Sealants.
11. Screw inner socket into rack part and tighten at the specified torque.





12. Decide on the neutral position for the rack.

Standard
Rack stroke "L" : Refer to Specifications.

13. Install rear cover cap to gear sub-assembly.

CAUTION:
Make sure that the projection of rear cover cap is aligned with the marking position of gear housing assembly.





14. Apply recommended thread sealant to the thread (2 turns thread), and then screw in the adjusting screw until it reaches height "H" from gear housing assembly measured before disassembling.
Use Genuine High Performance Thread Sealant or equivalent. Refer to Recommended Chemical Products and Sealants.
15. Move rack assembly 10 strokes throughout the full stroke so that the parts can fit with each other.





16. Measure pinion rotating torque within �180� of neutral position of the rack assembly using the preload gauge [SST] and preload adapter [SST]. Stop the gear at the point where highest torque is read.
17. Loosen adjusting screw and retighten to 5.4 N�m (0.55 kg-m, 48 in-lb), and then loosen by 20 to 40�.





18. Measure pinion rotating torque using the preload adapter [SST]
and preload gauge [SST] to make sure that the measured value is within the standard. Readjust if the value is outside the standard. Replace steering gear assembly if the value is outside the standard after readjusting or adjusting screw rotating torque is 5
N�m (0.51 kg-m, 44 in-lb) or less.





19. Apply recommended liquid gasket to inner socket and turn pinion fully to left with inner socket installed to gear housing assembly.





20. Set dial gauge as shown in the figure. Measure vertical movement of rack assembly when pinion is turned clockwise with torque of 19.6 N�m (2.0 kg-m, 14 ft-lb). Readjust adjusting screw angle if the measured value is outside the standard. Replace steering gear assembly if the measured value is still outside the standard or adjusting screw rotating torque is 5 N�m (0.51 kg-m, 44 in-lb) or less.










21. Install large end of boot to gear housing assembly.
22. Install small end of boot to inner socket boot mounting groove.
23. Install boot clamp to boot small end.





24. Install large side of boot clamp.

CAUTION:
Never reuse boot clamp.
- Tighten large side of boot with boot clamp (stainless wire).

Wire length "L" : 370 mm (14.57 in)

- Wrap clamp around boot groove for two turns. Insert a flatbladed screwdriver in loops on both ends of wire. Twist 4 to 4.5 turns while pulling them with force of approximately 98 N
(10 kg, 22 lb).





- Twist boot clamp as shown. Pay attention to relationship between winding and twisting directions.
- Twisted point of clamp is in the opposite side of adjusting screw (1) as shown in the figure (to prevent contact with other parts).





- Bent cut end of the wire toward rack axial as shown in the figure after twisting the wire 4 to 4.5 turns so that cut end does not contact with boot.

CAUTION:
Keep gap from cylinder tube 5 mm (0.20 in) or more.





25. Install cylinder tubes to gear housing assembly.
26. Adjust inner socket to standard length L, and then tighten lock nut to the specified torque. Refer to "COMPONENTS". Check length of inner socket L again after tightening lock nut. Make sure that the length is the standard.






Standard
Inner socket length "L" : Refer to Specifications.


CAUTION:
Adjust toe-in after this procedure. Length achieved after toe-in adjustment is not necessary the above value.