10. Power Steering Fluid
A: RECOMMENDED AIR BLEEDING AND
POWER STEERING FLUID
Recommended power steering fluid Manufacturer
ATF DEXRON II or ATF DEXRON IIEB.P.
CALTEX
CASTROL
MOBIL
SHELL
TEXACO
1) Feed the specified fluid with its level being about 5 cm
(2.0 in) lower than the mouth of tank.
2) Continue to turn steering wheel slowly from lock to lock
until bubbles stop appearing in the tank while keeping the
fluid at that level.
3) In case air is absorbed to deliver bubbles into piping
because the fluid level is lower, leave it about half an hour
and then do the step 2) all over again.
4) Start, and idle the engine.
5) Continue to turn steering wheel slowly from lock to lock
again until bubbles stop appearing in the tank while keep-
ing the fluid at that level.
It is normal that bubbles stop appearing after three times
turning of steering wheel.
6) In case bubbles do not stop appearing in the tank, leave
it about half an hour and then do the step 5) all over again.
7) Stop the engine, and take out safety stands after jack-
ing up vehicle again.
Then lower the vehicle, and idle the engine.
8) Continue to turn steering wheel from lock to lock until
bubbles stop appearing and change of the fluid level is
within 3 mm (0.12 in).
9) In case the following happens, leave it about half an
hour and then do step 8) again.
(1) The fluid level changes over 3 mm (0.12 in).
(2) Bubbles remain on the upper surface of the fluid.
(3) Grinding noise is generated from oil pump.
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4-3SERVICE PROCEDURE
10. Power Steering Fluid
10) Check the fluid leakage at flare nuts after turning
steering wheel from lock to lock with engine running.
CAUTION:
Before checking, wipe off any fluid on flare nuts and
piping.
In case the fluid leaks from flare nut, it is caused by
dust (or the like) and/or damage between flare and
tapered seat in piping.
So remove the flare nut, tighten again it to the speci-
fied torque after cleaning flare and tapered seat. If flare
or tapered seat is damaged, replace it with a new one.
11) Inspect fluid level on flat and level surface with engine
“OFF”by indicator of filler cap.
If the level is at lower point or below, add fluid to keep the
level in the specified range of the indicator. If at upper point
or above, drain fluid by using a syringe or the like.
Fluid capacity:
0.7(0.7 US qt, 0.6 Imp qt)
B4M0563
(1) Check at temperature 21°C (70°F) on reservoir sur-
face of oil pump.
(2) Check at temperature 60°C (140°F) on reservoir
surface of oil pump.
82
4-3SERVICE PROCEDURE
10. 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.
83
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.
84
4-3DIAGNOSTICS
1. Power Steering
3. MEASUREMENT OF STEERING EFFORT
*4
Measure steering efforts in stand still with engine idling on
concrete road.
Result: 29.4 N (3.0 kg, 6.6 lb) or less in both directions
GOOD
NOT GOOD
Adjust backlash.
Measure steering efforts in stand still with engine stalled on
concrete road.
Result: 294.2 N (30.0 kg, 66.2 lb) or less in both directions
NOT GOOD GOOD*4 When turning steering more
quickly than necessary from
a direction to the other direc-
tion at an engine speed over
2,000 rpm, steering effort
may be heavy. This is caused
by flow characteristic of oil
pump and is not a problem.
Adjust backlash.
Remove universal joint.
Measure steering wheel effort.
Result: Maximum force is 2.26 N (0.23 kg, 0.51 lb) or less in
both directions.
Fluctuation width is 1.08 N (0.11 kg, 0.24 lb) or less.
GOOD
NOT GOOD
Check, readjust, replace if
necessary.
Measure folding torque of the joint.
Result: 5.49 N (0.56 kg, 1.23 lb) or less for long yoke
8.43 N (0.86 kg, 1.90 lb) or less for short yoke
GOOD
NOT GOOD
Replace with a new one.
Check front wheels for unsteady revolution or rattling and brake
for dragging.
GOOD
NOT GOOD
Inspect, readjust, replace if
necessary.
Remove tie-rod ends.
(To be continued.)
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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.
94
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.
95
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.
96
4-3DIAGNOSTICS
1. Power Steering