1999 SUBARU LEGACY Service Repair Manual

: Control valve is inoperative. Replace
control valve itself or control valve andpinion as a single unit with new ones.
C: MEASUREMENT OF STEERING EFFORT
B4M1142A
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1) Measurement of steering effort is as shown in
the figures.
B4M0146
B4M0147
2) Measurement of folding torque of universal joint
is as shown in the figures.
G4M0199
G4M0200
G4M0201
G4M0202
3) Using ST, measure resistances of gearbox.
ST 926230000 SPANNER
Rotating resistance:
Straight-ahead position within 30 mm (1.18
in) from rack center
Less than 11.18 N (1.14 kg, 2.51 lb)
Maximum allowable torque
15.7 N (1.6 kg, 3.5 lb)
G4M0203
Sliding resistance:
Right-turn steering
304 N (31 kg, 68 lb) or less
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G4M0204
Left-turn steering
304 N (31 kg, 68 lb) or less
G4M0205
D: FLUID LEAKAGE
CAUTION:
It is likely that although one judges fluid
leakage, there is actually no leakage. This is
because the fluid spilt during the last mainte-
nance was not completely wiped off. Be sure to
wipe off spilt fluid thoroughly after mainte-
nance.
B4M0564B
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Fluid leaking area Possible cause Corrective action
Leakage from connecting portions of
pipes and hoses, numbered with (1) thru
(9) in figureInsufficient tightening of flare nut, catch-
ing dirt or the like, damage to flare or
flare nutLoosen and retighten, if ineffective,
replace.
Poor insertion of hose, poor clamping Retighten or replace clamp.
Damaged O-ring Replace O-ring pipe or hose with new
one, if ineffective, replace gearbox also.
Leakage from hose (10) and (11) in fig-
ureCrack or damage in hose Replace with a new one.
Crack or damage in hose hardware Replace with a new one.
Leakage from surrounding of cast iron
portion of oil pump (12) and (13) in fig-
ureDamaged O-ring Replace O-ring.
Damaged gasket Replace gasket.
Leakage from oil tank, (14) and (15) in
figureCrack in oil tank, (14) Replace oil tank.
Damaged O-ring, (15) Replace O-ring.
Leakage from filler neck (16) Damaged cap packing Replace cap.
Crack in root of filler neck Replace oil tank.
High fluid level *1 Adjust fluid level.
Leakage from surrounding of power cyl-
inder of gearbox, (17) in figureDamaged oil seal Replace oil seal.
Leakage from control valve of gearbox,
(18) and (19) in figureDamaged packing or oil seal Replace problem parts.
Damage in control valve Replace control valve.
*1 Fluid level is specified at optimum position (range) for ordinary use. Accordingly, if the vehicle is used often under hard
conditions such as on very rough roads or in mountainous areas, fluid may bleed out from cap air vent hole. This is not
a problem. 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 frequency than usual.
E: NOISE AND VIBRATION
CAUTION:
Don't keep the relief valve operated over 5 sec-
onds at any time or inner parts of the oil pump
may be damaged due to rapid increase of fluid
temperature.
NOTE:
IGrinding 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 condition.
IOil 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 pro-
vided that the noise eliminates when the vehicle is
running.
IWhen stopping with service brake and/or park-
ing brake applied, power steering can be operated
easily due to its light steering effort. If doing so, thedisk 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 sys-
tem.
IThere may be a little vibration around the steer-
ing devices when turning steering wheel at
standstill, even though the component 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 combined 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 ªDº range for automatic trans-
mission vehicle.
Trouble Possible cause Corrective action
Hiss noise (continuous)
While engine is running.Relief valve emits operating sound when steering wheel is
completely turned in either direction. (Don't keep this condition
over 5 seconds.)Normal
Relief valve emits operating sound when steering wheel is not
turned. This means that the relief valve is faulty.Defective
Replace oil pump.
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Trouble Possible cause Corrective action
Rattling noise (intermittent)
While engine is running.Interference with adjacent parts Check clearance.
Correct if necessary.

Loosened installation of oil pump, oil tank, pump bracket, gear-
box or crossmemberRetighten.
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 columnRetighten or replace.
Sound generates from the inside of gearbox or oil pump. Replace the gearbox or oil
pump.
Knocking
When turning steering wheel
in both direction with small
angle repeatedly at engine
ON or OFF.Excessive backlash
Loosened lock nut for adjusting backlashAdjust and retighten.
Loosened tightening or play of tie-rod, tie-rod end Retighten or replace.
Grinding noise (continuous)
While engine is running.Vane pump aeration Inspect and retighten fluid line
connection.
Refill fluid and vent air.
Vane pump seizing Replace oil pump.
Pulley bearing seizing of oil pump Replace oil pump.
Folded hose, flat pipe Replace.
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 pulley Clean or replace.
Sizzling noise (continuous)
While engine is running.Fluid aeration Fix wrong part causing aera-
tion.
Replace fluid and vent air.
Damaged pipe of gearbox Replace pipe.
Abnormal inside of hose or pipe
Flat hose or pipeRectify or replace.
Abnormal inside of oil tank Replace.
Removed oil tank cap Install cap.
Whistle (continuous)
While engine is running.Abnormal pipe of gearbox or abnormal inside of hose Replace bad parts of gearbox
or hose.
Whine or growl (continuous or
intermittent)
While engine is running with/
without steering turned.Loosened installation of oil pump, oil pump bracket Retighten.
Abnormal inside of oil pump, hose Replace oil pump, hose, if the
noise can be heard when run-
ning as well as stand still.
Torque converter growl air conditioner compression growl Remove power steering pul-
ley belt and confirm.
Creaking noise (intermittent)
While engine is running with
steering turned.Abnormal inside of gearbox Replace bad parts of gear-
box.
Abnormal bearing for steering shaft Apply grease or replace.
Generates when turning steering wheel with brake (service or
parking) applied.If the noise goes off when
brake is released, it is normal.
Vibration
While engine is running with/
without steering turned.Too low engine speed at start Adjust and instruct custom-
ers.
Vane pump aeration Fix wrong part.
Vent air.
Damaged valve in oil pump, gearbox Replace oil pump, bad parts
of gearbox.
Looseness of play of steering, suspension parts Retighten.
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F: CLEARANCE TABLE
CAUTION:
This table lists various clearances that must be
correctly adjusted to ensure normal vehicle
driving without interfering noise, or any other
faults.
LocationMinimum
allowance
mm (in)LocationMinimum
allowance
mm (in)
(1) Crossmember Ð Pipe 5 (0.20) (6) Exhaust pipe Ð Pipe 15 (0.59)
(2) DOJ Ð Shaft or joint 14 (0.55) (7) Exhaust pipe Ð Gearbox bolt 15 (0.59)
(3) DOJ Ð Valve housing 11 (0.43) (8) Side frame Ð Hose A and B 15 (0.59)
(4) Pipe Ð Pipe 2 (0.08) (9) Cruise control pump Ð Hose A and B 15 (0.59)
(5) Stabilizer Ð Pipe 5 (0.20) (10) Pipe portion of hose A Ð Pipe portion of
hose B1.5 (0.059)
(11)AT cooling hose Ð Joint 20 (0.79)
B4M0565B
G: BREAKAGE OF HOSES
CAUTION:
Although surface layer materials of rubber
hoses have excellent weathering resistance,
heat resistance and resistance for low tem-
perature brittleness, they are likely to be dam-
aged chemically by brake fluid, battery
electrolyte, engine oil and automatic transmis-
sion fluid and their service lives are to be very
shortened. It is very important to keep thehoses free from before mentioned fluids and to
wipe out immediately when the hoses are
adhered with the fluids.
Since resistances for heat or low temperature
brittleness are gradually declining according to
time accumulation of hot or cold conditions for
the hoses and their service lives are shortening
accordingly, it is necessary to perform careful
inspection frequently when the vehicle is used
in hot weather areas, cold weather area and/or
a driving condition in which many steering
operations are required in short time. Particu-
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larly continuous work of relief valve over 5 sec-
onds causes to reduce service lives of the
hoses, the oil pump, the fluid, etc. due to over
heat.So, avoid to keep this kind of condition when
servicing as well as driving.
Trouble Possible cause Corrective action
Pressure hose burst Excessive holding time of relief status Instruct customers.
Malfunction of relief valve Replace oil pump.
Poor cold characteristic of fluid Replace fluid.
Forced out return hose Poor connection Correct.
Poor holding of clip Retighten.
Poor cold characteristic of fluid Replace fluid.
Fluid bleeding out of hose
slightlyWrong layout, tensioned Replace hose.
Excessive play of engine due to deterioration of engine
mounting rubberReplace defective parts.
Improper stop position of pitching stopper Replace defective parts.
Crack on hose Excessive holding time of relief status Replace.
Instruct customer.
Excessive tightening torque for return hose clip Replace.
Power steering fluid, brake fluid, engine oil, electrolyte
adhere on the hose surfaceReplace.
Pay attention on service work.
Too many times use in extremely cold weather Replace.
Instruct customers.
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MEMO:
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