Isuzu Trooper (2000 year). Manual — part 50

2A–30

POWER ASSISTED SYSTEM

Power Steering Pump Disassembled View

412RX005

Legend

(1) Bolt
(2) Suction Pipe
(3) O-ring
(4) Front Housing
(5) Snap Ring
(6) Shaft Assembly
(7) Bearing
(8) Shaft
(9) Retaining Ring

(10) Oil Seal

(11) O-ring

(12) O-ring
(13) Gasket

(14) Rear Housing Assembly and Pump Cartridge
(15) Side Plate
(16) Rotor and Vane
(17) Pin
(18) Cam
(19) Rear Housing
(20) Bolt
(21) Spring
(22) Retaining Ring
(23) Filter
(24) Valve
(25) O-ring
(26) Connector
(27) Pressure Switch

Disassembly

1. Clean the oil pump with solvent (plug the discharge

and suction ports to prevent the entry of solvent). Be
careful not to expose the oil seal of shaft assembly to
solvent.

2. Remove the bolt.
3. Remove the suction pipe.
4. Remove the O-ring.
5. Remove the connector.
6. Remove the O-ring.

7. Remove the valve.
8. Remove the retaining ring.
9. Remove the filter.

10. Remove the spring.

11. Remove the snap ring.

12. Remove the shaft assembly.
13. Remove the retaining ring.
14. Remove the oil seal.

CAUTION: When removing the oil seal, be careful
not to damage the housing.

POWER ASSISTED SYSTEM

2A–31

15. Remove the bolt.
16. Remove the rear housing assembly and the pump

cartridge.

17. Remove the gasket.
18. Remove the O-ring.
19. Remove the O-ring.
20. Remove the front housing.
21. Remove the side plate.
22. Remove the rotor and vane.
23. Remove the cam.
24. Remove the pin.
25. Remove the rear housing.
26. Remove the pressure switch.

Inspection and Repair

Make all necessary adjustments, repairs, and part
replacements if wear, damage, or other problems are
discovered during inspection.

Rotor

442RS002

Check that the groove in the vane is free from excessive
wear and that the vane slides smoothly. When part
replacement becomes necessary, the pump cartridge
should be replaced as a subassembly.

Vane

442RS003

Sliding faces of the vane should be free from wear.
(Particularly the curved face at the tip that contact with the
cam should be free from wear and distortion). When part
replacement becomes necessary, the pump cartridge
should be replaced as a subassembly.

Cam

The inner face of the arm should have a uniform contact
pattern without a sign of step wear. When part
replacement becomes necessary, the pump cartridge
should be replaced as a subassembly.

Side Plate

The sliding faces of parts must be free from step wear
(more than 0.01 mm), which can be felt by the finger nail.
The parts with minor scores may be reused after lapping
the face.

Valve

The sliding face of the valve must be free from burrs and
damage. The parts with minor scores may be reused after
smoothing with emery cloth (#800 or finer).

Shaft

Oil seal sliding faces must be free from a step wear which
can be felt by the finger nail. Needle bearing fitting face
must be free from damage and wear.

O-ring, Oil Seal, Retaining Ring

Be sure to discard used parts, and always use new parts
for installation. Prior to installation, lubricate all seals and
rings with power steering fluid.

Pressure Switch

Check the switch operation as follows:
With engine idling and A/C on, turn the steering wheel
fully to the left; compressor should interrupt and engine
idle speed will increase. Shut off A/C and again turn

2A–32

POWER ASSISTED SYSTEM

steering fully to the left; engine idle will increase. If system
fails to function properly, disconnect connector at the
pressure switch and repeat system check while testing
continuity across disconnected SW connector.

Reassembly

1. Install rear housing.
2. Install pin.
3. Install cam.
4. Install the rotor with punch mark facing the front

housing.

442RS004

5. Install the vanes with curved face in contact with the

inner wall of the cam.

442RS005

6. Install side plate.

CAUTION: When installing side plate, be careful not
to damage its inner surface. Damaged side plate may
cause poor pump performance, pump seizure or oil
leakage.

7. Install front housing.
8. Install a new o-ring and be sure to discard used parts.

9. Install a new o-ring and be sure to discard used parts.

10. Install a new gasket and be sure to discard used

parts.

11. Install rear housing and pump cartridge.

12. Install bolt and tighten it to the specified torque.

Torque: 17.6 N·m (12.8 lb ft)

13. Install a new oil seal and be sure to discard used

parts.

CAUTION: When installing the oil seal, be careful
not to damage the oil seal contacting surface of the
housing.

14. Install shaft assembly.
15. Install snap ring.
16. Install spring.
17. Install retaining ring.
18. Install filter.
19. Install valve.
20. Install retaining ring.
21. Install a new o-ring and be sure to discard used parts.
22. Install connector and tighten it to the specified torque.

Torque: 19.6 N·m (14.3 lb ft)

23. Install a new o-ring and be sure to discard used parts.
24. Install suction pipe.
25. Install bolt and tighten it to the specified torque.

Torque: 15.7 N·m (11.5 lb ft)

26. Install pressure switch and tighten it to the specified

torque.

Torque: 20 N·m (14 lb ft)

POWER ASSISTED SYSTEM

2A–33

Main Data and Specifications

General Specifications

Oil pump

Type

Vane

Operating
fluid

ATF DEXRON



–III

Torque Specifications

E02RX005