Overhaul

Hydraulic Power Steering Pump Overhaul

Exploded View





Special Tools Required

- Pulley Holder 07ZAB-S5A0100
- Driver Handle, 15 x 135L 07749-0010000
- Bearing Driver Attachment, 28 x 30 mm 07946-1870100

Disassembly

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

1. Remove the power steering pump Removal and Replacement.

2. Hold the power steering pump (A) in a vise with soft jaws (B), then hold the pulley (C) with the pulley holder (D), and remove the pulley nut (E) and pulley. Be careful not to damage the pump housing with the jaws of the vise.






3. Remove the inlet joint and the O-ring.

4. Loosen the flow control valve cap with a hex wrench, and remove the cap, the O-ring, the spring, and the flow control valve.

5. Remove the pump cover and pump cover seal.

6. Remove the outer side plate, the cam ring, the rotor, the vanes, the side plate and the O-rings.

7. Remove the snap ring, then remove the subvalve from the pump housing.

8. Remove the 40mm snap ring, then remove the driveshaft by tapping the shaft end with a soft face hammer.

9. Remove the pump seal from the pump housing.

Inspection

10. Check the flow control valve for wear, burrs, and other damage to the edges of the grooves in the valve.





11. Inspect the bore of the flow control valve on the pump housing for scratches and wear.

12. Slip the flow control valve back in the pump housing, and check that it moves in and out smoothly. If OK, go to step 14; if not, replace the pump as an assembly. The flow control valve (A) is not available separately.






13. Attach a hose (A) to the end of the flow control valve (B) as shown. Then submerge the flow control valve in a container of power steering fluid (C), and apply compressed air in the hose.

- If air bubbles leak through the valve at less than 98 kPa (1.0 kgf/cm2, 14.2 psi), replace the pump as an assembly. The flow control valve is not available separately.
- If the flow control valve is OK, set it aside for reassembly later.





14. Inspect the ball bearing by rotating the outer race slowly. If you feel any play (axial or radial) or roughness, remove the faulty ball bearing (A) and install a new one (B).






Reassembly

15. Align the pin (A) of the subvalve (B) with the oil passage (C) in the pump housing, and push the subvalve into place, then install the snap ring (D).






16. Install a new pump seal (with its grooved side facing in) (A) into the pump housing (B) by hand first, then drive it in using the 15 x 135L driver handle and the 28 x 30 mm bearing driver attachment until there is no step at the top of the pump seal, and the seal is fully seated in the pump housing.






17. Position the driveshaft (A) in the pump housing, then press it in with the appropriate size socket (B) as shown.





18. Install the 40 mm snap ring (C) with its beveled edge facing out.

19. Coat a new pump cover seal (A) with power steering fluid, and install it into the groove in the pump cover (B).





20. Install the outer side plate (C) over the 4.5 mm pin (D) and the 5.0 mm pin (E) with its arrow marks stamped (F) facing down.

21. Set the cam ring (A) over the two roll pins with the "-" marks (B) facing down.






22. Install the rotor (A) to the pump cover (B).





23. Set the 10 vanes (C) into the grooves in the rotor. Make sure that the round ends (D) of the vanes are in contact with the sliding surface of the cam ring.

24. Coat a new 15.2 mm O-ring (A) with power steering fluid, and install it into the groove in the side plate (B).





25. Install the side plate on the cam ring (C) by aligning the roll pin set holes (D) in the side plate with the roll pins (E).

26. Coat a new 51 mm O-ring (A) with power steering fluid, and position it in the bottom of the pump housing.





27. Install the pump cover assembly (B) in the pump housing. Tighten the bolts to the specified torque alternating in two or more steps.

28. Coat the flow control valve (A) with power steering fluid, then install it and the spring (B) in the pump housing.





29. Coat a new 16.7 mm O-ring (C) with power steering fluid, and install it on the flow control valve cap (D), then install the cap on the pump housing. Tighten it to the specified torque.

30. Coat a new 13 mm O-ring (A) with power steering fluid, and install it on the inlet joint (B). Install the inlet joint on the pump housing.






31. Install the pulley (A), then loosely install the pulley nut (B). Hold the steering pump in a vise with soft jaws. Be careful not to damage the pump housing with the jaws of the vise.





32. Hold the pulley using the pulley holder, and tighten the pulley nut to the specified torque.

33. Check that the power steering pump turns smoothly by turning the pulley by hand. If it turns hard, loosen the four flange bolts on the cover, then retighten them in same manner as in step 29 and retest. If the pump is still hard to turn, replace the pump.

34. Reinstall the power steering pump Removal and Replacement.