SST491B
SST090B ON-VEHICLE
SERVICE
Bleeding Hydraulic System
1. Raise frontendofvehicle untilwheels areclear ofthe
ground.
2. Add fluid intooiltank tospecified level.Thenquickly turn
steering wheelfullytoright andleftand lightly touchsteer-
ing stoppers.
Repeat steering wheeloperation untilfluid level nolonger
decreases.
3. Start engine.
Repeat step2.above.
• Incomplete airbleeding willcause thefollowing tooccur.
When thishappens, bleedairagain.
a. Air bubbles inreservoir tank
b. Clicking noiseinoil pump
c. Excessive buzzinginoil pump
Fluid noise mayoccur inthe valve oroil pump. Thisiscommon
when thevehicle isstationary orwhile turning thesteering
wheel slowly. Thisdoes notaffect theperformance ordurabil-
ity ofthe system.
Checking SteeringWheelTurning Force(For
power steering)
1. Park vehicle onalevel, drysurface andsetparking brake.
2. Start engine.
3. Bring power steering fluiduptoadequate operating temper-
ature. [Make suretemperature offluid isapproximately 60
to 80°C (140to176°F).]
Tires needtobe inflated tonormal pressure.
4. Check steering wheelturning forcewhen steering wheel
has been turned 360°from theneutral position.
Steering wheelturning force: •
39 N(4 kg, 9Ib) orless
5.
If
steering wheelturning forceisout ofspecification, check
rack sliding force.
a. Disconnect steeringcolumnlowerjointandknuckle arms
from thegear.
b. Start andrunengine atidle tomake suresteering fluidhas
reached normaloperating temperature.
c. Pull tie-rod slowlytomove itfrom neutral position to
::l::
11.5
mm
(::l::
0.453 in)atspeed of3.5 mm (0.138 in)/s.Check that
rack sliding forceiswithin specification.
Average racksliding force:
152.0 -240.3 N(15.5 -24.5 kg,34.2 -54.0 Ib)
Maximum forcedeviation:
98 N(10 kg, 22Ib)
6.
If
rack sliding forceisnot within specification, overhaul
steering gearassembly.
7. Ifrack sliding forceisOK, inspect steering column.Referto
ST-13.
ST-7
ST27091000
.. :Direction ofoil flow Low-pressure
hose SST834-AON-VEHICLE
SERVICE
Checking Hydraulic System
Before starting, checkbelttension, drivingpulleyandtirepres-
sure. 1. Set Tool. Open shut-off valve.Thenbleed air.(See "Bleed-
ing Hydraulic System"ST-7.)
2. Run engine.
Make suretemperature offluid intank rises to60 to80°C (140
to 176°F).
WARNING:
Warm upengine withshut-off valvefullyopened. Ifengine is
started withshut-off valveclosed, fluidpressure inoil pump
increases tomaximum. Thiswillraise oiltemperature abnor-
mally.
3. Check pressure withsteering wheelfullyturned toleft and
right positions withengine idlingat1,000 rpm.
CAUTION:
Do not hold thesteering wheelinalocked position formore
than 15seconds.
Oil pump maximum standardpressure:
7,649 -8,238 kPa(76.5 .82.4 bar,
78 -84 kg/cm
2,
1,109-1,194 psi)
4.
If
oil pressure isbelow thestandard pressure, slowlyclose
shut-off valveandcheck pressure.
• When pressure reachesstandard pressure, gearisdam-
aged.
• When pressure remainsbelowstandard pressure, pumpis
damaged.
CAUTION: Do not close shut-off valveformore than15seconds.
5.
If
oil pressure ishigher thanstandard pressure, checkoil
pump flowcontrol valve.
6. After checking hydraulic system,removeToolandaddfluid
as necessary. Thencompletely bleedairout ofsystem.
S1-8
