Part 1

Steering Gearbox Overhaul

Steering Gearbox:

Special Tools Required
^ Cylinder end seal remover attachment 07NAD-SR3020A
^ Pilot collar 07GAF-PH70100
^ Valve seal ring sizing tool 07NAG-SR3090A
^ Sleeve seal ring guide 07YAG-S2X0100
^ Sleeve seal ring sizing tool, 36 mm 07ZAG-S5A0100
^ Attachment, 32 x 35 mm 07746-0010100
^ Driver 07749-0010000
^ Piston seal ring guide 07HAG-SF10100
^ Piston seal ring sizing tool 07HAG-SF1020A or 07HAG-SF10200
^ Cylinder end seal slider 07ZAG-S5A0300
^ Pincers Oetiker 1098 or equivalent, commercially available

NOTE: Refer to the Exploded View as needed during this procedure.

Removal
1. Remove the steering gearbox.

Disassembly
2. Remove the boot bands (A) and tie-rod clips (B). Pull the boot away from the ends of the steering gearbox.





3. Unbend the lock washers (A).





4. Hold the flat surface sections (A) of the steering rack with a wrench (B), and unscrew both rack ends (C) with a wrench (D). Be careful not to damage the rack surface with the wrench.





5. Remove the lock washer (E) and stop rubber (F).
6. Loosen the locknut (A), then remove the rack guide screw (B).





7. Remove the spring (C) and the rack guide (D) from the gearbox housing.
8. Remove the cylinder lines from the gearbox.





9. Drain the fluid from the cylinder fittings by slowly moving the steering rack back and forth.
10. Remove the two flange bolts, then remove the valve body unit (A) from the gearbox (B). Remove the O-ring (C), and discard it.





11. Drill a 3 mm (0.12 in.) diameter hole about 2.5-3.0 mm (0.10-0.12 in.) in depth in the staked point (A) on the cylinder. Do not allow metal shavings to enter the cylinder side on the gearbox housing. After removing the cylinder end (B), remove any burrs at the staked point.





12. Hold the gearbox housing using a C-clamp (commercially available) (A) and the wooden blocks (B) as shown. Do not clamp the cylinder part of the gearbox housing in the vise. Then remove the cylinder end (C).





13. Install a commercially available bearing separator (A) in the gearbox housing as shown.





14. Place an appropriate size deep socket wrench (B) on the steering rack (C).
15. Set the steering gearbox in a press so the gearbox housing side points upward, then press the cylinder end seal (D) and steering rack out of the gearbox. Hold the steering rack to keep it from falling when pressed clear. Be careful not to damage the inner surface of the cylinder side on the gearbox housing with the tool.
16. Install the cylinder end seal remover attachment so it will fit through the rack guide hole of the gearbox housing. Insert a 24" long, 3/8" drive extension (A), and install it on the attachment. Make sure the attachment is securely positioned on the backup ring edges. Be careful not to damage the inner surface of the cylinder with the attachment.





17. Place the steering gearbox in a press, then remove the cylinder end seal (A) and backup ring (B) from the gearbox by pressing on the 24" long, 3/8" drive extension.

Note these items when pressing the cylinder end seal:
^ Keep the tool straight to avoid damaging the cylinder wall. Check the tool angle, and correct it if necessary, when removing the cylinder end seal.
^ Use a press to remove the cylinder end seal. Do not try to remove the seal by striking the tool; striking the tool would break the backup ring, and the cylinder end seal would remain in the gearbox.





18. Carefully pry the piston seal ring (A) and O-ring (B) off the rack piston. Be careful not to damage the inside of the seal ring groove and piston edges when removing the seal ring.





19. Before removing the valve housing (A), apply vinyl tape (B) to the splines on the pinion shaft.





20. Separate the valve housing from the pinion shaft/valve using a press.
21. With your finger, check the inner wall of the valve housing where the seal ring slides. If there is a step in the wall, the housing is worn. Replace it.

NOTE: There may be sliding marks from the seal ring on the wall of the valve housing. Replace the valve housing only if the wall is stepped.





22. Check for wear, burrs, and other damage to the edges of the grooves in the sleeve.

NOTE: The pinion shaft and sleeve are a precision matched set. If either the pinion shaft or sleeve must be replaced, replace both parts as a set.





23. Remove the snap ring (A) and sleeve (B) from the pinion shaft.





24. Using a cutter or an equivalent tool, cut and remove the four seal rings from the sleeve. Be careful not to damage the edges of the sleeve grooves and outer surface when removing the seal rings.





25. Using a cutter or an equivalent tool, cut the valve seal ring (A) and O-ring (B) at the cutting groove position (C) in the pinion shaft. Remove the valve seal ring and O-ring. Be careful not to damage the edges of the pinion shaft groove and outer surface when removing the valve seal ring and O-ring.





26. Remove the valve oil seal (A) and wave washer (B) from the pinion shaft.

Note these items during disassembly:
^ Inspect the ball bearing (C) by rotating the outer race slowly. If there is any excessive play or wear, replace the pinion shaft and sleeve as an assembly.
^ The pinion shaft and sleeve are a precise fit; do not intermix old and new pinion shafts and sleeves.





27. Press the valve oil seal (A) and roller bearing (B) out of the valve housing using a hydraulic press and pilot collar.





28. Clean the disassembled parts with solvent, and dry them with compressed air. Do not dip rubber parts in the solvent.

Reassembly
29. Apply vinyl tape (A) to the stepped portion of the pinion shaft, and coat the surface of the vinyl tape with power steering fluid.





30. Install the wave washer (B).
31. Coat the inside surface of the new valve oil seal (C) with power steering fluid, and install the seal with its grooved side facing opposite the bearing, then slide it over the pinion shaft, being careful not to damage its sealing lip (D).
32. Apply vinyl tape (A) to the splines and stepped portion of the shaft, and coat the surface of the vinyl tape with power steering fluid.





33. Fit the new O-ring (B) in the groove of the pinion shaft. Then slide the new valve seal ring (C) over the shaft and in the groove on the pinion shaft.
34. Remove the tape, and apply power steering fluid to the surface of the valve seal ring (A).





35. Apply power steering fluid to the inside of the valve seal ring sizing tool. Set the larger diameter end of the sizing tool over the valve seal ring, and move the sizing tool up and down several times to make the valve seal ring fit in the pinion shaft groove.
36. Remove the sizing tool, turn it over, slide the smaller diameter end over the valve seal ring. Move it up and down several times to make the valve seal ring fit snugly in the pinion shaft groove.