Subaru Legacy IV (2008 year). Manual - part 971

PS-46

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

B: INSTALLATION

1. H4 MODEL

1) Install the oil pump to the bracket.

Tightening torque:

15.7 N·m (1.6 kgf-m, 11.6 ft-lb)

Tightening torque:

48.4 N·m (4.9 kgf-m, 35.7 ft-lb)

2) Attach the installation bolts of the power steering
pump bracket.

Tightening torque:

<Ref. to PS-6, OIL PUMP, COMPONENT, Gen-
eral Description.>

3) After installing the oil pump, fill the fluid while ro-
tating the pulley by hand to bleed air from the oil
pump.

CAUTION:
Always fill the oil pump with the fluid to prevent
abnormal noise and seizure of the oil pump.

4) Connect the pressure hose and suction hose.

Tightening torque:

Eye bolt

40 N·m (4.1 kgf-m, 29.5 ft-lb)

CAUTION:
Be careful not to twist hoses. Twisted hoses
may contact other parts.
• Non-turbo model

• Turbo model

5) Connect the power steering pressure switch
connector.
6) Install the V-belts to the oil pump.
7) Check the tension of the V-belt.
<Ref. to ME(H4SO)-40, INSPECTION, V-belt.>
8) Tighten the lock bolt of the belt tension nut.

Tightening torque:

25 N·m (2.5 kgf-m, 18.4 ft-lb)

9) Install the pulley belt cover.
10) Install the air intake duct.
<Ref. to IN(H4DOTC)-9, INSTALLATION, Air In-
take Duct.> <Ref. to IN(H4SO)-8, INSTALLATION,
Air Intake Duct.>
11) Connect the ground cable to battery.

PS-00128

PS-00137

PS-00188

(1) Suction hose

(2) Pressure hose

(1) Suction hose

(2) Pressure hose

PS-00688

(1)

(2)

(2)

PS-00459

(1)

PS-47

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

12) Fill with the specified power steering fluid.
<Ref. to PS-53, Power Steering Fluid.>

CAUTION:
Never start the engine before filling with fluid;
otherwise the vane pump may become seized.

2. H6 MODEL

1) Install the oil pump to the bracket.

Tightening torque:

15.7 N·m (1.6 kgf-m, 11.6 ft-lb)

Tightening torque:

37.3 N·m (3.8 kgf-m, 27.5 ft-lb)

2) Tighten the bolt which attaches the power steer-
ing pump bracket.

Tightening torque:

<Ref. to PS-6, OIL PUMP, COMPONENT, Gen-
eral Description.>

3) After installing the oil pump, fill the fluid while ro-
tating the pulley by hand to bleed air from the oil
pump.

CAUTION:
Always fill the oil pump with the fluid to prevent
abnormal noise and seizure of the oil pump.
4) Connect the pressure hose and suction hose.

Tightening torque:

Eye bolt

40 N·m (4.1 kgf-m, 29.5 ft-lb)

CAUTION:
Be careful not to twist hoses. Twisted hoses
may contact other parts.

5) Connect the power steering pressure switch
connector.
6) Install the tensioner adjuster.
7) Install the V-belts.
8) Install the pulley belt cover.
9) Connect the ground cable to battery.
10) Pour the specified power steering fluid. <Ref. to
PS-53, Power Steering Fluid.>

CAUTION:
Never start the engine before filling with fluid;
otherwise the vane pump may become seized.

PS-00229

PS-00702

PS-00701

(1) Suction hose

(2) Pressure hose

PS-00700

(1)

(2)

PS-48

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

C: INSPECTION

1. BASIC INSPECTION

Perform the following inspection procedures and replace faulty parts.

No.

Parts

Inspection

Corrective action

1

Oil pump (Exterior)

(1) Crack, damage or oil leakage

Replace the oil pump with a new part.

(2) Play of pulley shaft

Measure the radial play and axial play.
If any of these exceeds the service limit, replace the 
oil pump with a new part.

2

Pulley

(1) Damage

Replace with a new part.

(2) Bend

Measure the V groove deflection.
If it exceeds the service limit, replace the pulley with a 
new part.

3

Oil pump (Interior)

(1) Faulty or seized of vane pump

Check the rotating resistance of pulley.
If it exceeds the service limit, replace the oil pump with 
new part.

(2) Bend in the shaft or damage to 
bearing

If the a string is wrapped on the pulley and rotated, 
and the oil pump emits a noise that is markedly differ-
ent in tone and loudness from a sound of a new oil 
pump, replace the oil pump with a new part.

4

O-ring

Cracking or deterioration

Replace with a new part.

5

Bracket

Crack

Replace with a new part.

PS-49

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

2. SERVICE LIMIT

Make a measurements as follows. If it exceeds the
service limit, replace with a new part.

CAUTION:
• When securing the oil pump on a vise, hold
the oil pump with the least possible force be-
tween two pieces of wood.
• Do not set the outside of flow control valve or
pulley on a vise; otherwise outside or pulley
might be deformed. Select properly sized wood
pieces.
1) Play of the pulley shaft

Condition:

P: When applying the force of 9.8 N 
(1.0 kgf, 2.2 lb)

Service limit:

Play in the radial direction (Direction 

 

)

0.4 mm (0.016 in) or less

Axial play (Direction 

 

)

0.9 mm (0.035 in) or less

2) Deflection of the pulley groove

Service limit:

1.0 mm (0.039 in) or less

NOTE:
Read the value for one surface of V ditch, and then
the value for another off the dial gauge.

3) Rotating resistance of pulley

Service limit:

Maximum load: 9.22 N (0.94 kgf, 2.07 lb) or 
less

NOTE:
• A rather higher value may be indicated when pul-
ley starts turning.
• Measure the load during rotation to make a judg-
ment.

(1) Dial gauge

(1) Dial gauge

PS-00145

P

(1)

PS-00146

P

(1)

(1) Dial gauge

(1) Spring scale

PS-00147

PS-00148