Subaru Legacy IV (2008 year). Manual - part 972

PS-50

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

3. HYDRAULIC PRESSURE

NOTE:
• To measure hydraulic pressure correctly, be
sure to complete all the items in “INSPECTION”,
prior to performing the measurement. <Ref. to PS-
54, INSPECTION, General Diagnostic Table.>
• Do not leave the valve of pressure gauge closed
or hold the steering wheel at lock for 5 seconds or
more in any case, this can damage the oil pump.
• Before attaching a pressure gauge, place a
waste cloth at locations where fluid can be expect-
ed to spill. Wipe off any spilt fluid completely after
the measurement.
1) Regular pressure measurement

(1) Connect the ST1, ST2 and ST3.

ST1

925711000

PRESSURE GAUGE

ST2

34099AC020 ADAPTER HOSE B

ST3

34099AC010 ADAPTER HOSE A

(2) Remove the air intake duct.
(3) Disconnect the pipe C from pump.
(4) Using the gasket (Part No. 34621AC021)
and bolt (Part No. 34620AC010), attach the
ST2 to pump instead of pressure hose.
• Non-turbo model

• Turbo model

(5) Attach the ST3 to the end of pressure hose
which is removed from pump.
(6) Replenish power steering fluid up to the
specified level.

(7) Open the valve, and start the engine.
(8) Measure the regular pressure.

ST1

925711000

PRESSURE GAUGE

ST2

34099AC020 ADAPTER HOSE B

ST3

34099AC010 ADAPTER HOSE A

Service limit:

981 kPa (10 kg/cm

, 142 psi) or less

(9) If it is not within the specification, replace the
problem part for the following problems. (Pipe
or hose clogged, leaks from fluid line, and mix-
ture of foreign matter in fluid line)

2) Measure the relief pressure.

(1) Using the STs, measure the relief pressure.
(2) Close the valve.
(3) Measure the relief pressure.

ST1

925711000

PRESSURE GAUGE

ST2

34099AC020 ADAPTER HOSE B

ST3

34099AC010 ADAPTER HOSE A

Service limit:

H4 non-turbo model:

7,350 — 8,050 kPa
(75 — 82 kg/cm

, 1,067 — 1,165 psi)

H4 turbo model:

8,100 — 8,800 kPa
(83 — 90 kg/cm

, 1,174 — 1,276 psi)

H6 model:

8,300 — 9,000 kPa
(85 — 92 kg/cm

, 1,204 — 1,305 psi)

(4) If it is not within the specification, replace the
oil pump.

(1) Suction hose

(2) Pressure hose

(1) Suction hose

(2) Pressure hose

PS-00688

(1)

(2)

PS-00459

(1)

(1) Valve

PS-00152

PS-00153

PS-51

Oil Pump

POWER ASSISTED SYSTEM (POWER STEERING)

3) Measure the working pressure.

(1) Using the ST, measure the working pres-
sure.
(2) Open the valve.
(3) Measure the working pressure of control
valve by turning steering wheel from stop to
stop.

ST1

925711000

PRESSURE GAUGE

ST2

34099AC020 ADAPTER HOSE B

ST3

34099AC010 ADAPTER HOSE A

Service limit:

7,650 — 8,330 kPa
(78 — 85 kg/cm

, 1,110 — 1,208 psi)

(4) If it is out of specification, measure the
steering effort. <Ref. to PS-57, MEASURE-
MENT OF STEERING EFFORT, INSPEC-
TION, General Diagnostic Table.> If it is not
within specification, replace the control valve it-
self or control valve and pinion as a single unit,
using new parts.

(1) Valve

PS-00152

PS-52

Reservoir Tank

POWER ASSISTED SYSTEM (POWER STEERING)

8. Reservoir Tank

A: REMOVAL

1) Drain fluid from the reservoir tank.
2) Disconnect the hose from reservoir tank.

CAUTION:
To prevent foreign matter from entering the
hose and pipe, cover the open ends of them
with clean cloth.

3) Remove the reservoir tank from the body.

B: INSTALLATION

1) Install the reservoir tank to the body.

Tightening torque:

13 N·m (1.32 kgf-m, 9.6 ft-lb)

2) Connect the hose to the reservoir tank.

3) Replenish power steering fluid up to the speci-
fied level. <Ref. to PS-53, Power Steering Fluid.>

C: INSPECTION

Check the reservoir tank for cracks, breakage or
damage. If a failure is found, replace the reservoir
tank.

(1) Reservoir tank

(2) Suction hose

(3) Return hose

(1) Reservoir tank

(2) Suction hose

(3) Return hose

PS-00799

(3)

(1)

(2)

PS-00799

(3)

(1)

(2)

PS-53

Power Steering Fluid

POWER ASSISTED SYSTEM (POWER STEERING)

9. Power Steering Fluid

A: SPECIFICATION

B: INSPECTION

1) Check the power steering fluid for deterioration
or contamination. If the fluid is highly deteriorated
or contaminated, drain it and refill with new fluid.
2) Check the joints and units for oil leakage. If any
oil leaks are found, repair or replace the applicable
part.
3) Inspect the fluid level of reservoir tank with vehi-
cle on level surface and engine stopped.
If the level is at “MIN.” point or below, add fluid to
keep the level in the specified range of the indica-
tor. If fluid level is at “MAX.” point or above, drain
fluid by using a syringe or the like.

(1) Check at power steering fluid temperature
20°C (68°F); read the fluid level on the “COLD”
side.
(2) Check at power steering fluid temperature
80°C (176°F); read the fluid level on the “HOT”
side.

C: REPLACEMENT

1) Lift up the vehicle.
2) Remove the crossmember support.
3) Remove the pipe joint in the center of gearbox,
and connect the vinyl hose to the pipe and joint.
Wipe fluid off while turning the steering wheel.
4) Add the specified fluid to reservoir tank at “MAX”
level.
5) Continue to turn the steering wheel slowly from
lock to lock until the bubbles stop appearing on oil
surface while keeping the fluid at the level in the
Step 4).
6) If the steering wheel is turned in a low fluid level
condition, air will be sucked into the pipe. If air has
entered, leave it for about half an hour and then re-
peat step 5) again.
7) Start the engine and let it idle.
8) Continue to turn the steering wheel slowly from
lock to lock again until the bubbles stop appearing
on oil surface, while keeping the fluid at the level in
Step 4).
Normally bubbles will stop appearing after turning
the steering wheel from lock to lock three times.
9) In case bubbles do not stop appearing in the
tank, leave it for about half an hour and then repeat
from step 4) again.
10) Lower the vehicle, and then idle the engine.
11) Continue to turn the steering wheel from lock to
lock until the bubbles stop appearing and change of
the fluid level is within 3 mm (0.12 in).
12) In case the following happens, leave it about
half an hour and then perform step 8) to 11) again.

(1) The fluid level changes by 3 mm (0.12 in) or
more.
(2) Bubbles remain on the upper surface of the
fluid.
(3) Grinding noise is generated from oil pump.

13) Check the fluid leakage after turning steering
wheel from lock to lock with engine running.

Recommended power steering fluid

SUBARU ATF or ATF DEXRON III

PS-00463

HOT MAX

COLD MAX

HOT MIN

COLD MIN

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