Isuzu KB P190. Service manual — part 70

POWER-ASSISTED STEERING SYSTEM 3B-19

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, suction pipe and O-ring.
3. Remove the connector, O-ring, relief valve and

spring.

4. Remove the bolt, rear housing and O-ring.
5. Remove the snap ring.
6. Remove the shaft assembly.
7. Remove the oil seal.

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

8. Remove the pump cartridge assembly from the front

housing.

9. Remove two O-rings.

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 cam 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 (0.0004 in)), which can be felt by
the finger nail.
The parts with minor scores may be reused after lapping
the face.

Relief 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. Bushing fitting face
must be free from damage and wear.

O-ring, Oil Seal, Snap 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.

3B-20 POWER-ASSISTED STEERING SYSTEM

Reassembly

1. Install oil seal to front housing. Be sure to discard

used oil seal, and always use new parts for
installation.

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

2. Install shaft assembly.
3. Install the vanes to roter with curved face in contact

with the inner wall of cam.

442RS005

4. Install roter and vanes to cam.
5. Install pin to front housing.
6. Install two new O-rings to front housing. Be sure to

discard used O-ring.

7. 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.

8. Install pump cartridge assembly to front housing.
9. Install snap ring to shaft end.
10. Install rear housing with a new O-ring. Be sure to

discard used O-ring. Then install bolt and tighten it
to specified torque.

Torque: 25 N･

･･

･m (2.5 kgf････m/18 lb････ft)

11. Install suction pipe with a new O-ring. Be sure to

discard used O-ring. Then install bolt and tighten it
to specified torque.

Torque: 10 N･

･･

･m (1.0 kgf････m/87 lb････in)

12. Install relief valve and spring.
13. Install connector with a new O-ring. Be sure to

discard used O-ring. Tighten the connector to
specified torque.

Torque: 59 N･

･･

･m (6.0 kgf････m/43 lb････ft)

Main Data and Specifications

General Specifications

Oil pump

Type

Vane

Operating

fluid

ATF DEXRON

®

―III

POWER-ASSISTED STEERING SYSTEM 3B-21

Torque Specifications

4JH1-TC, 4JA1-T

N･m (kgf･m/Ib･ft)

RTW73BLF000901

3B-22 POWER-ASSISTED STEERING SYSTEM

Power Steering Pump (4JJ1-TC, 4JK1-TC)

Power Steering Pump and Associated Parts

RTW53BMF000201

Legend

(1) Pump Assembly

(2) Flexible Hose

(3) Bolt

(4) Suction Hose

(5) Nut

Removal

1. Remove the cooler compressor drive belt.

2. Place a drain pan below the pump.

3. Disconnect the suction hose.

4. Disconnect the flexible hose.

5. Remove the power steering fixing nut, and remove

the pump assembly.

Installation

1. Install the pump assembly. Tighten the fixing nut to

the specified torque.

Torque:

25 N·m (2.5 kgf·m/18 lb·ft)

2. Install the flexible hose.

Tighten the bolts to the specified torque.

Torque: 8 N·m (0.8 kgf·m/69 lb·in)

3. Install the cooler compressor drive belt.

4. Connect the suction hose, then fill the power steering

fluid and bleed the power steering system.

Refer to Bleeding the Power Steering System in this

section.