Disassembly and Assembly
Steering Gear Without Torque Specifications:
DISASSEMBLY
CAUTION: Do not clamp the steering gear assembly in a vise by the power cylinder housing.
1. Remove dust cover.
2. Remove retaining ring.
3. Remove back up ring.
4. Remove oil seal.
- Clean the faces of the extended stub shaft.
- Plug the hose fitting on the inlet side.
- Remove the oil seal by blowing compressed air through the hole in the outlet side.
5. Remove lock nut.
- Remove the adjusting screw lock nut and turn the adjusting screw counter-clockwise to remove the preload between the sector gear and the rack piston.
6. Remove the top cover bolts and the top cover assembly.
- Holding the top cover stationary, turn the adjusting screw clockwise to raise and free to cover, then remove the cover with O-ring.
7. Bring the stub shaft into straight-ahead position. Do not force the sector shaft off the gear box with a hammer or other impact tools then remove sector shaft.
8. Remove ball-nut and valve housing assembly.
- Always keep the ball nut and valve housing assembly in a horizontal position to prevent them from traveling to the end of the worm shaft and damaging the ball tubes.
9. Remove O-ring.
10. Remove seal ring.
11. Remove O-ring.
12. Remove gear box.
INSPECTION AND REPAIR
Inspect the following parts for wear, damage or any other abnormal conditions.
- Bearing
- Ball-nut and valve housing
- Sector shaft
- Top cover
- Gearbox
- Needle bearing
- Dust seal
- Seal ring
- Gasket
Ball-Nut Rotation
Hold the ball nut and valve housing assembly vertically and see if the ball-nut lowers by turning smoothly. If the ball-nut does not lower smoothly, check the worm shaft for bending and foreign matter.
NOTE: When testing the ball nut and valve housing assembly, do not let it travel all the way to the end of worm shaft, or damage to the ball tubes will result.
- Check sector shaft outside diameter.
Limit: 31.7 mm (1.25 inch)
Dust Seal And Seal Ring Setting
- Note the dust seal (1) and the seal ring (2) installation direction. Always install a new part.
- Apply a thin coat of power steering fluid to lip of each part.
Gasket Setting
- Note the gasket (1) installation direction.
- Apply a thin coat of power steering fluid to lip of each part.
REASSEMBLY
1. Install gear box.
2. Apply a thin coat of power steering fluid to the new O-ring (2) and be sure to discard used part, then install O-ring.
3. Apply a thin coat of power steering fluid to the new seal ring (1) and be sure to discard used part, then install seal ring.
4. Apply a thin coat of power steering fluid to the new O-ring and be sure to discard used part, then install O-ring.
5. Install ball-nut and valve housing assembly.
- Always keep the ball screw and valve housing assembly in a horizontal position (avoid holding it vertically), or the rack piston will fall off onto the end of the worm, causing the rack piston to slip out of the worm shaft and ball to fall out.
- Be careful not to drop the O-ring into the valve housing.
- Tighten the valve housing bolts to the specified torque.
Torque: 47 Nm (35 ft. lbs.)
6. Install sector shaft.
- Tape the sector shaft serrations to protect the seal ring from damage.
- Align the center tooth of ball nut with that of the sector shaft.
7. Install O-ring.
8. Install top cover assembly and tighten the fixing bolts to specified torque.
Torque: 47 Nm (35 ft. lbs.)
9. Adjust the backlash between the worm gear and the ball nut.
- With the worm gear rotating, set it to the straight ahead position.
- Set the worm shaft preload to below 10 kg cm with the sector shaft adjusting screw.
- Measure the worm shaft preload with the worm gear turned 450° both to the right and to the left. The worm gear preload in these positions should be 0.4 - 0.6 Nm (4 - 6 kg cm) lower than in the straight ahead position.
- Lock the sector shaft adjusting screw with the lock nut.
Lock nut torque: 41 Nm (30 ft. lbs.)
10. Apply a thin coat of power steering fluid to oil seal lip of each part, then use installer J-26508 to install oil seal.
11. Install back up ring and position the chamfered face (outer circumference) towards the oil seal.
12. Install retaining ring and position the chamfered face (outer circumference) towards the oil seal.
13. Install dust cover.