Disassemble

Dissassemble



NOTE:
- When repairing the power steering pump, always use the repair kit of the respective manufacturer.
- Scrupulous cleanliness is essential when performing any work on the power steering pump.
- The work should be performed, wherever possible, on a plastic base. Chamois cloths are particularly suitable for this kind of work. A strict standard should be applied when examining steering parts. Always replace the part in question in cases of doubt.

NOTE:
For application identification refer to "Steering : Power Steering Pump : Service and Repair : Overhaul Procedures : Application and ID" Application and ID


Disassembly:





1. Unscrew breather cap (47), take off end cover (45).
2. Unscrew self-locking nut (6) downwards from the stud bolt, take off plastic sleeve (60), spring (43), and filter set (41).





3. On the Vickers/LUK power steering pump, the fluid reservoir (35) can be removed. Replace O-ring.
On the ZF power steering pump, the fluid reservoir is cast on to the pump housing (2).





4. Unscrew bolts (25) and take off the bearing flange (4). Examine ground face of bearing flange (4) for signs of damage.





5. Take off pressure plate (3) and cam insert (6).
Examine ground face of pressure plate as well as sliding face of vanes on cam insert (6) for signs of scoring and wear.
There must not be any perceptible scoring present on the sliding face of the cam insert.





6. Take locking ring (18) off the drive shaft (11). Replace locking ring.





7. Detach rotor (7) with a plastic.headed hammer from the drive shaft (11) and take off together with the vanes (10 vanes). Examine the vanes (16) in the grooves of the rotor (7); they must slide easily in the rotor.

Examine sliding face of vanes at cam insert (6) for signs of wear. If necessary, repair power steering pump by using the "Pump operation" repair kit.





8. Remove drive shaft (11) from the bearing flange (4).
Examine drive shaft (11) and bearing bushes for signs of wear.





9. Use a screwdriver to press radial seal ring (13) out of the bearing flange (4).




34a Vickers/LUK pump
34b ZF pump

10. Remove locking ring (34a or 34b).

CAUTION: When removing locking ring, ensure that the housing bore is not damaged.





11. Remove flow control valve (32) and compression spring (30) from the pump housing (2).





12. Clamp flow control valve (32) in a vise at the part which is not ground, and unscrew valve screw (53) of the overpressure valve. Remove sealing cone (51) and compression spring (50).
Examine the ground faces of the flow control valve (32) and the bore in the pump housing for signs of wear and damage. If scoring is detected on the sliding faces, the power steering pump must be replaced.

13. Check both sealing cones (high-pressure expansion hose, return pipe connection). Replace misshapen sealing cones. This is done by cutting a thread with M7 or M10 a few thread turns deep into the sealing cone. Withdraw the sealing cone from the housing with an M7 or M10 bolt.
Fit new sealing cone into the housing and press into the housing by screwing in the high-pressure expansion hose or the return pipe.