Diesel Data: Automotive Repair

Overhaul




Hydraulic Power Steering Pump Overhaul

Exploded View





Special Tools Required

- Pulley Holder 07ZAB-S5A0100
- Bearing Driver Attachment, 32 x 35 mm 07746-0010100
- Driver Handle, 15 x 135L 07749-0010000

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

Disassembly

1. Remove the power steering pump Removal and Replacement.

2. Drain the remaining fluid from the power steering pump Testing and Inspection.

3. 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 a vise.






4. Remove the inlet joint and the 13.0 mm O-ring.

5. Remove the pressure control valve cap, the 16.7 mm O-ring, the pressure control valve, and the valve spring.

6. Remove the pump housing cap, the 12.7 mm O-ring, and the pump preload spring.

7. Remove the pump cover, the 13.0 mm O-ring, and the pump cover seals.

8. Pull out the roll pin.

9. Remove the outer case, the cam ring, the rotor, the vanes, and the side plate.

10. Remove the rubber seal and the slipper seal from the outer case.

11. Remove the 23.8 mm O-ring and 51.0 mm O-ring from the bottom of the housing.

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

13. Remove the pump seal from the pump housing.

Inspection

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





15. Inspect the bore of the pressure control valve on the pump housing for scratches and wear.

16. Slip the pressure control valve (A) back in the pump housing, and check that it moves in and out smoothly. If OK, go to step 17; if not, replace the pump as an assembly. The pressure control valve is not available separately.






17. Attach a hose (A) to the end of the pressure control valve (B) as shown. Then submerge the pressure 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 pressure control valve is not available separately.
- If the pressure control valve is OK, set it aside for reassembly later.





18. 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).





19. Inspect each part shown with an asterisk in the Exploded View. If any of them are worn or damaged, replace the pump as an assembly.

Reassembly

20. Install the new pump seal (A) (with its grooved side facing in) into the pump housing (B) by hand first, then drive it in using the driver handle (C) and the attachment (D) until the pump seal is fully seated in the pump housing. Do not apply more than 1,370 N (140 kgf, 308 lbf) of pressure.






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





22. Install the 40 mm internal snap ring (C) with its reduced edge facing out.

23. Coat the new 23.8 mm O-ring (A) with power steering fluid, then position it on the bottom (B) of the pump housing.






24. Coat the new pump cover seals (A) and new 13.0 mm O-ring (B) with power steering fluid, then position them into the grooves on the pump cover (C).

NOTE: Be careful not to install the inlet joint O-ring because they are the same sizes.






25. Install the outer case (A) by aligning the slot (B) inside the outer case with the pump cover roll pin hole (C). Be sure that the slit (D) on the outer case is in the direction shown.





26. Apply power steering fluid to the new rubber seal (E) (black), and install it in the slot (F) of the outer case.

27. Apply power steering fluid to the new slipper seal (G) (white), and install it on top of the rubber seal you just installed.

28. Install the cam ring (A) by aligning the slot (B) with the slot (C) in the outer case.





29. Install the roll pin (D) into the slots between the cam ring and outer case, then push the roll pin into the set hole (E).

30. Install the rotor (A) into the cam ring (B).





31. Set the 11 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.

32. Place the side plate (A) on the cam ring, and align the roll pin set hole (B) with the roll pin (C).





33. Coat the new 51.0 mm O-ring (D) with power steering fluid, then position it into the groove on the side plate.

34. Install the pump housing (A) over the pump cover assembly (B).






35. Align the bolt holes in the pump cover (A) with the threaded holes in the pump housing. Install the flange bolts loosely first, then tighten the flange bolts to the specified torque alternating in two or more steps.






36. Push in the cam ring (A) from the pump housing cap hole (B) with a flat-tip screwdriver to make sure the cam ring is fully seated against the outer case.






37. Install the pump preload spring (A) in the pump housing.





38. Coat the new 12.7 mm O-ring (B) with power steering fluid, and install it on the pump housing cap (C).

39. Install the pump housing cap on the pump housing, and tighten it to the specified torque.

40. Install the pressure control valve spring (A) in the pump housing.





41. Coat the pressure control valve (B) with power steering fluid, and install it in the pump housing.

42. Coat the new 16.7 mm O-ring (C) with power steering fluid, and install it on the pressure control valve cap (D).

43. Install the pressure control valve cap on the pump housing. Tighten it to the specified torque.

44. Coat the new 13.0 mm O-ring (A) with power steering fluid, and install it on the inlet joint (B).





45. Install the inlet joint on the pump housing.

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





47. Hold the pulley with the pulley holder (D), and tighten the pulley nut to the specified torque.

48. 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 pump cover, then retighten them in the same manner as in step 35. Retest. If the power steering pump is still hard to turn, replace the power steering pump.

49. Install the power steering pump Removal and Replacement.