1997 SUBARU LEGACY power steering fluid

1. Power Steering
1. STEERING CONDITION
Heavy steering
effort in all rangeHeavy steering
effort at stand stillSteering wheel
surges when turn-
ing.Vehicle leads to
one side or the
other.Poor return of
steering wheel to
center
Pulley belt
1. Unequal length of pulley
belts
2. Adhesion of oil and
grease
3. Loose or damage of pul-
ley belt
4. Poor uniformity of pulley
belt cross section
5. Pulley belt touches to
pulley bottom
6. Poor revolution of pulleys
except oil pump pulley
7. Poor revolution of oil
pump pulley
GOOD
NOT GOOD
Adjust or replace.Fluid line
1. Folded hose
2. Flattened pipe
GOOD
NOT
GOODReform or
replace.
Tire and rim
1. Flat tire
2. Mix use of different tires
3. Mix use of different rims
4. Abnormal wear of tire
5. Unbalance of remained
grooves
6. Unbalance of tire pres-
sure
GOOD
NOT
GOODFix or replace.
Tire and rim
1. Improper tires out of
specification
2. Improper rims out of
specification
3. Tires not properly
inflated*1
GOOD
NOT GOOD
Replace or reinflate.Front alignment
1. Improper or unbalance
caster
2. Improper or unbalance
toe-in
3. Loose connection of sus-
pension
GOOD
NOT
GOODAdjust or
retighten.
Fluid
1. Low fluid level
2. Aeration
3. Dust mix
4. Deterioration of fluid
5. Poor warming-up of fluid
*2
GOOD
NOT GOOD
Refill, bleed air, replace or
instruct customer.Others
1. Damaged joint assembly
2. Unbalanced height
3. One-sided weight
GOOD
Measure steering effort.
NOT
GOODReplace, adjust or
instruct customer.
Idling speed
1. Lower idling speed
2. Excessive drop of
idling speed at start
or at turning steering
wheel *3
GOOD
NOT GOOD
Adjust or instruct customer.
*1 If tires and/or rims are wider, the load to power steering system is the more. Accordingly, in a
condition, for example before fluid warms-up, relief valve may work before maximum turning angle.
In this case, steering effort may be heavy. When measured hydraulic pressure is normal, there is
no abnormal thing.
*2 In cold weather, steering effort may be heavy due to increased flow resistance of cold fluid. After
warming up engine, turn steering wheel from stop to stop several times to warm up fluid. Then if
steering effort reduces normally, there is no abnormal thing.
*3 In cold weather or with insufficient warm-up of engine, steering effort may be heavy due to exces-
sive drop of idling when turning steering wheel. In this case, it is recommended to start the vehicle
with increasing engine speed than usual. Then if steering effort reduces normally, there is no
abnormal thing. Measure hydraulic pressure.
GOOD
Measure steering effort.








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4-3DIAGNOSTICS
1. Power Steering

2. MEASUREMENT OF HYDRAULIC PRESSURE
CAUTION:
Be sure to complete all items aforementioned in
“STEERING CONDITION”4-3 [K101], prior to measur-
ing hydraulic pressure. Otherwise, pressure can not be
measured correctly.
Measure regular pressure at
idling with valve opened.
GOOD
NOT GOOD
Flattened pipes or hosesReplace bad parts.
NOT GOOD
Leakage of fluid lineReplace.
NOT GOOD
Obstacle in fluid lineReplace fluid or component of
fluid line.
Measure relief pressure at
idling with valve closed.
GOOD
NOT GOOD
Poor work of relief valveReplace oil pump.
NOT GOOD
Fluid leakage inside oil pump
NOT GOOD
Excessive wear of vane pump
mechanism
Measure working pressure of
control valve at idling with
valve opened, turning steering
wheel from stop to stop.NOT GOOD
Poor work of control valveReplace valve assembly or
pinion and valve assembly.
CAUTION:

Do not leave the valve of pressure gauge closed or
hold the steering wheel at stop end for 5 seconds or
more in any case, as the oil pump may be damaged
due to long keep of these conditions.

Put cotton cloth waste at a place where fluid drops
before pressure gauge is installed. Wipe off split fluid
thoroughly after the measurement.
NOTE:
Keep engine idling during the measurement.


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4-3DIAGNOSTICS
1. Power Steering

B4M1193A
1) Install STs to power steering pump.
(1) Drain the power steering fluid about 0.35
(0.4 US
qt, 0.3 Imp qt) from oil tank.
(2) Remove two bolts securing power steering pipes to
engine.
(3) Install ST1, 2 and 3 between power steering pump
and pipes using gasket (Part No. 34621AC020) and
bolt (Part No. 34620AC010).
ST1 925711000 PRESSURE GAUGE
ST2 34099AC020 ADAPTER B
ST3 34099AC010 ADAPTER A
(4) Replenish power steering fluid up to specified level.
2) Using STs, measure regulator pressure.
Regulator pressure:
981 kPa (10 kg/cm
2, 142 psi) or less
B4M1162A
3) Using STs, measure relief pressure.
Relief pressure:
7,159—7,748 kPa
(73—79 kg/cm
2, 1,038—1,123 psi)
84
4-3DIAGNOSTICS
1. Power Steering

4. FLUID LEAKAGE (LHD MODEL)
CAUTION:
It is likely that although one judges fluid leakage, there
is actually no leakage. This is because the fluid spilt
during the last maintenance was not completely wiped
off. Be sure to wipe off spilt fluid thoroughly after
maintenance.
Leakage from connecting portions of
pipes and hoses, numbered with1thru9in figure
Insufficient tightening of flare nut,
catching dirt or the like, damage to
flare or flare nutLoosen and retighten, if ineffective,
replace.
Poor insertion of hose, poor clamp-
ingRetighten or replace clamp.
Damaged O-ringReplace O-ring pipe or hose with
new one, if ineffective, replace gear-
box also.
Leakage from hose10and11in
figureCrack or damage in hoseReplace with a new one.
Crack or damage in hose hardware
Leakage from surrounding of cast
iron portion of oil pump12and13in
figureDamaged oil sealReplace oil seal.
Damaged oil seal
Leakage from oil tank,14and15in figureCrack in oil tank,14Replace oil tank.
Damaged O-ring,15Replace O-ring.
Leakage from filler neck16Damaged cap packingReplace cap.
Crack in root of filler neckReplace oil tank.
High fluid level *5Adjust fluid level.
Leakage from surrounding of power
cylinder of gearbox,17in figureDamaged oil sealReplace bad parts.
Leakage from control valve of
gearbox,18and19in figureDamaged packing or oil seal
Damage in control valve
*5 Fluid level is specified at optimum position (range) for ordinary use. Accordingly, if the vehicle is used often under hard con-
ditions such as on very rough roads or in mountainous areas, fluid may bleed out from cap air vent hole. This is not a prob-
lem. If a customer complains strongly and is not likely to be satisfied with the leakage, lower the fluid level to the extent that
fluid will not bleed out under the conditions described, and have the customer check the fluid level and its quality more fre-
quency than usual.
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4-3DIAGNOSTICS
1. Power Steering

5. FLUID LEAKAGE (RHD MODEL)
CAUTION:
It is likely that although one judges fluid leakage, there
is actually no leakage. This is because the fluid spilt
during the last maintenance was not completely wiped
off. Be sure to wipe off spilt fluid thoroughly after
maintenance.
Leakage from connecting portions of
pipes and hoses, numbered with1thru9in figure
Insufficient tightening of flare nut,
catching dirt or the like, damage to
flare or flare nutLoosen and retighten, if ineffective,
replace.
Poor insertion of hose, poor clamp-
ingRetighten or replace clamp.
Damaged O-ringReplace O-ring pipe or hose with
new one, if ineffective, replace gear-
box also.
Leakage from hose10and11in
figureCrack or damage in hoseReplace with a new one.
Crack or damage in hose hardware
Leakage from surrounding of cast
iron portion of oil pump12and13in
figureDamaged oil sealReplace oil seal.
Damaged oil seal
Leakage from oil tank,14and15in figureCrack in oil tank,14Replace oil tank.
Damaged O-ring,15Replace O-ring.
Leakage from filler neck16Damaged cap packingReplace cap.
Crack in root of filler neckReplace oil tank.
High fluid level *5Adjust fluid level.
Leakage from surrounding of power
cylinder of gearbox,17in figureDamaged oil sealReplace bad parts.
Leakage from control valve of
gearbox,18and19in figureDamaged packing or oil seal
Damage in control valve
*5 Fluid level is specified at optimum position (range) for ordinary use. Accordingly, if the vehicle is used often under hard con-
ditions such as on very rough roads or in mountainous areas, fluid may bleed out from cap air vent hole. This is not a prob-
lem. If a customer complains strongly and is not likely to be satisfied with the leakage, lower the fluid level to the extent that
fluid will not bleed out under the conditions described, and have the customer check the fluid level and its quality more fre-
quency than usual.
91
4-3DIAGNOSTICS
1. Power Steering

6. NOISE AND VIBRATION
*6
Hiss noise (continu-
ous)
While engine is run-
ning with maximum
turning angle.
Relief valve soundGenerates at max.
turning angle.Normal (Don’t keep
this condition over 5
seconds.)
Generates without
steering operation.Defective
Replace oil pump.
Rattling noise
(intermittent)
While engine is run-
ning.Interference with adjacent partsCheck clearance.
[Refer to next article
6.]
Correct if necessary.
Loosened installation of oil pump, oil tank, pump bracket,
gearbox or crossmember.Retighten.
Loosened installation of oil pump pulley or other pulley(s).Retighten.
Loosened linkage or play of steering or suspension.
Loosened tightening of joint or steering column.Retighten or replace.
Sound generates from the inside of gearbox or oil pump.Replace the gearbox
or oil pump.
Knocking
When turning steer-
ing wheel in both
direction with small
angle repeatedly at
engine ON or OFF.Excessive backlash
Loosened lock nut for adjusting backlash.Adjust and retighten.
Loosened tightening or play of tie-rod, tie-rod end.Retighten or replace.
*6 Don’t keep the relief valve operated over 5 sec. at any time or inner parts of the oil pump may be damaged due to rapid increase
of fluid temperature.
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4-3DIAGNOSTICS
1. Power Steering

*7
Grinding noise (continuous)
While engine is running.
Vane pump aerationInspect and retighten fluid line
connection.
Refill fluid and vent air.
Vane pump seizingReplace oil pump.
Pulley bearing seizing of oil pump
Folded hose, flat pipeReplace.
Squeal, squeak
(intermittent or continuous)
While engine is running.Maladjustment of pulley belt
Damaged or charged pulley belt
Unequal length of pulley beltsAdjust or replace.
(Replace two belts as a set.)
Run out or soilage of V-groove
surface of oil pump pulleyClean or replace.
Sizzling noise (continuous)
While engine is running.Fluid aerationFix wrong part causing aeration.
Replace fluid and vent air.
Damaged pipe of gearboxReplace pipe.
Abnormal inside of hose or pipe
Flat hose or pipeRectify or replace.
Abnormal inside of oil tankReplace.
Removed oil tank capInstall cap.
Whistle (continuous)
While engine is running.Abnormal pipe of gearbox or
abnormal inside of hoseReplace bad parts of gearbox
or hose.
*7 Grinding noise may be heard immediately after the engine start in extremely cold condition. In this case, if the noise goes off
during warm-up there is no abnormal function in the system. This is due to the fluid characteristic in extremely cold condi-
tion.
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4-3DIAGNOSTICS
1. Power Steering

Whine or growl (continuous or
intermittent)
While engine is running with/
without steering turned.Loosened installation of oil pump,
oil pump bracketRetighten.
*8
Abnormal inside of oil pump, hoseReplace oil pump, hose, if the
noise can be heard when running
as well as stand still.
Torque converter growl
air conditioner compression growlRemove power steering pulley
belt and confirm.
Creaking noise (intermittent)
While engine is running with
steering turned.Abnormal inside of gearboxReplace bad parts of gearbox.
Abnormal bearing for steering
shaftApply grease or replace.
*9
Generates when turning steering
wheel with brake (service or park-
ing) applied.If the noise goes off when brake
is released, it is normal.
*10
Vibration
While engine is running with/
without steering turned.
Too low engine speed at startAdjust and instruct customers.
Vane pump aerationFix wrong part.
Vent air.
Damaged valve in oil pump, gear-
boxReplace oil pump, bad parts of
gearbox.
Looseness of play of steering,
suspension partsRetighten.
*8 Oil pump makes whine or growl noise slightly due to its mechanism. Even if the noise can be heard when steering wheel
is turned at stand still there is no abnormal function in the system provided that the noise eliminates when the vehicle is
running.
*9 When stopping with service brake and/or parking brake applied, power steering can be operated easily due to its light
steering effort. If doing so, the disk rotates slightly and makes creaking noise. The noise is generated by creaking between
the disk and pads. If the noise goes off when the brake is released, there is no abnormal function in the system.
*10 There may be a little vibration around the steering devices when turning steering wheel at standstill, even though the com-
ponent parts are properly adjusted and have no defects.
Hydraulic systems are likely to generate this kind of vibration as well as working noise and fluid noise because of com-
bined conditions, i.e., road surface and tire surface, engine speed and turning speed of steering wheel, fluid temperature
and braking condition.
This phenomena does not indicate there is some abnormal function in the system.
The vibration can be known when steering wheel is turned repeatedly at various speeds from slow to rapid step by step
with parking brake applied on concrete road and in“D”range for automatic transmission vehicle.
95
4-3DIAGNOSTICS
1. Power Steering