Power Steering Gear Service

Fig. 5 Power rack & pinion steering gear exploded view.:

Disassembly

1. Remove clamps securing rack boots, and pull back boots to expose tie rod joint.
2. Bend up tabs on tie rod lock plates, position rack as needed to secure rack with suitable spanner, then remove tie rods.
3. Disconnect and remove fluid lines.
4. Remove cap spring and spacer from rack adjuster pressure piece, Fig. 5.
5. Thread self-tapping screw into pressure piece, then remove pressure piece along with seal and plastic insulator.
6. Pull off cap protecting pinion steering spindle, then ensure that rack is centered.
7. Mark position of steering spindle, valve body housing and gear housing in relation to each other.
8. Remove valve housing bolts, the housing and pinion assembly, and the housing O-ring.
9. Remove pinion and thrust washer from valve housing, then the seal and bearing, noting installation position.
10. Mark position of cylindrical tube (22), Fig. 5, in relation to gear housing, then loosen ring nut and remove tube.
11. Withdraw rack assembly from gear housing, then remove piston assembly (11-14) and cylindrical tube (8), Fig. 5, from rack, noting installation position for assembly.
12. Remove seal, spacer, snap ring and friction washer (4-7) from tube (8), Fig. 5, then drive seal and support ring out of opposite end of tube.
13. Insert screwdriver through slot in bearing retainer in tube (22), Fig. 5, and drive remove seal and support ring.
14. Remove seal (1) and snap ring (18) from end of tube (22), Fig. 5.
15. Remove seal and piston ring from piston.
16. Inspect components and replace any that are damaged, deformed or excessively worn.

Assembly

Replace seals and O-rings, and coat seal and friction surfaces with suitable hydraulic fluid during assembly.
1. Replace pinion shaft seal in gear housing, as needed, ensure that seal is fully seated, then pack seal lip with grease.
2. Install support ring into tube (8), Fig. 5, with chamfer facing inside of tube, then press seal into tube with open end facing out.
3. Cover cuts in rack with cellophane tape to prevent seal damage, then slide tube (8) over rack and remove tape.
4. Install friction washer, snap ring, spacer and O-ring on end of tube (8), Fig. 5.
5. Install piston, washers, O-ring and circlips (11-14) on rack, Fig. 5, in position noted during disassembly.
6. Install O-ring and piston ring on rack piston, then coat assembly with hydraulic fluid.
7. Install support ring and seal (10) into tube (22), Fig. 5, ensuring that seal is fully seated and that open end faces up.
8. Measure and record thickness of snap ring (18), then install snap ring and new O-ring over end of tube (22).
9. Insert rack into tube assembly (22), slightly compressing piston ring to prevent damage, and ensure that tube is flush with friction washer (7), Fig. 5.
10. Lubricate rack teeth with grease, then insert rack assembly into gear housing and tighten ring nut.
11. Ensure that rack teeth are properly positioned and that mounting flanges on tube and housing are aligned horizontally, then torque ring nut. Ring nut torque is dependent upon thickness of snap ring (18), Fig. 5, recorded in step 8. If snap ring is .098 inch thick, torque ring nut to 87 ft.lbs. If snap ring is .138 inch thick, torque ring nut to 108 ft.lbs.
12. Install seals (88) and round seals (87) onto pinion valve body, ensuring that round seals are positioned on top, then coat assembly with hydraulic fluid.

Fig. 6 Rack centering measurement:

13. Center rack in gear housing, ensuring that distance between ends of rack and cylinder stops (A), Fig. 6, is 2.835 inches on both sides.
14. Coat pinion splines with grease, then insert pinion into gear housing, ensuring that marks made during disassembly are aligned.
15. Install new oil seal in valve body housing with open end facing in, then install the bearing, ensuring that both bearing and seal are fully seated.
16. Position valve body seal on gear housing, install valve body housing ensuring that matching marks are aligned and torque bolts to 14 ft.lbs.
17. Pack spindle cap with grease, then install cap, aligning tab on cap with slot in housing.
18. Install new seal and plastic insulator on rack adjuster pressure piece, then insert assembly into gear housing.
19. Install adjuster spring, spacer and cap, and torque cap bolts to 14 ft.lbs.
20. Install fluid lines, using new seals on union bolts, and torque union bolts to 14 ft.lbs.
21. Install rack boots, tie rod lock plates and tie rods, secure rack with suitable spanner and torque tie rods to 50-56 ft.lbs.
22. Secure rack boots with clamps, install steering gear and check operation.