wheel torque MITSUBISHI 3000GT 1991 Workshop Manual

37B-1
li 4-WHEEL STEERING
SYSTEM (4WS)
CONTENTSMWAA-0
CONTROL VALVE................................................9SPECIAL TOOLS....................................................2
POWER CYLINDER............................................6SPECIFICATIONS................................................2
REAR OIL LINEGeneral Specifications
....................................2....................................................10Lubricants...............................................:............2
REAR OIL PUMP....................................................11Service Specifications....................................2
LJ
SERVICE ADJUSTMENT PROCEDURES . . . . . .4TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._._._3Ball Joint Rotation Starting Torque Check
. . . .5Bleeding
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._______._4
Function Check
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Rear Oil Pump Discharge Flow Volume
Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._...........................5

37B-24-WHEEL STEERING SYSTEM (4WS) -Specifications / Special Tools
SPECIFICATIONS
GENERAL SPECIFICATIONSM37CA-B
Items
Power steering gear box
Type
Oil pump
Type
Displacement
cm”/rev. (cu.in./rev.)
Relief set pressure
MPa (psi)
Rear oil pump
Type
Displacement
cm’/rev. (cu.in./rev.)
Relief set pressure
MPa (psi)
Power cylinder
Type
Strokemm (in.)
Specifications
Rack and pinion
Vane type
9.6 (0.59)
8 (1,138)
Vane type
3.3 (0.20)
4 (569)
Hydraulic double action type
20 i.78) [one side 10 (.39)1
SERVICE SPECIFICATIONSM37CEB
Items
Standard value
Specifications
Rear oil pump displacement [at speedometer reading of
31 mph (50 km/h) for 30 seconds]liter (qts.)
Power cylinder ball joint rotation starting torqueNm (in.lbs.)
Power cylinder tie rod swing torqueN (Ibs.) [Nm (in.lbs.)]
Power cylinder slide resistanceN (Ibs.)
Approx. 1 .O (1.06)
0.5 (4) or less
9 - 55 (2 - 12) IO.5 - 3.0 (4 - 26)l
67 (15) or less
LUBRICANTSM37CD.B
,II
Items
Power steering fluid
Dust cover
Specified lubricant
MITSUBISHI PLUS
ATFiAutomatic Trans-mission fluid “DEXRON” or “DEXRON II”
‘Silicone grease
Quantity
1.45 liter (1.53 qts.)
As requiredSPECIAL TOOLS
M37DA-6
MB990993-01Power steering oilpressure gauge
Measurement of fluid flow volumeTSB Revision

4-WHEEL STEERING SYSTEM (4WS) - Troubleshooting
TROUBLESHOOTING
37B-3
M37EMKBefore inspecting, check the following items:
l Oil pump drive belt tension
lEnsure that the suspension has not been mod-@Power steering fluid level, and air in the system
ified
l Engine
Idle soeed and even idle
lTire and wheel size, specifications, air pressure,
l Oil leakage
balance and amount of wear
l Steering wheel type
l Wheel alignment
Malfunction symptom
4WS does not operateMalfunctioning system
Power cylinderInspection item
Tie rod swing torque
Power cylinder slide resistance
Rear oil pump
Flow volume check
Control valve
-
Poor steering feelingSteering gears and linkage
Rack cracks or deformationFeeling of friction in steering
Poor steering return
Steering wheel efforts
excessive
Control valve
Oil leakage from control valve jornt
Rear wheels cannot be
steered
Poor rear wheels return
Hydraulic pressure for rear
wheel is constantly high
Long rear wheel steering
delayPoor steering response
Poor steering returnPower cylinder
Oil lineOil reservoir
Control valve
Power cylinder
Rear oil pump
Power cylinder
Oil leakage from piston rod
Pressure hose breakage
Oil reservoir deformation or oil leakage
Stuck control valve spool
Stuck power cylinder
Relief valve remains open
Excessive power cylinder friction-
Looseness in power cylinder tie rod ball jo.int
Ball joint dust cover cracks
Poor rear wheel steeringresponsePoor rear wheel steeringrange
Poor steerability (extremetire wear)Control valve
Power cylinder
Rear oil pump
Power cylinder
Oil leakage from control valve spool
Oil leakage from power cylinder
Extreme oil pump internal wear
Tie rod length improperly adjusted after toe-inadjustment
[ TSB Revision

4-WHEEL STEERING SYSTEM (4WS) -Service Adjustment Procedures37B-5
Rubber hose
13FOOl
Graduated cylinder13FOOllFUNCTION CHECK
_M37FWAA
(1) Raise the vehicle so that all four wheels may turn freely.
(2) Start the engine, running the vehicle at an indicated speed
of about 80
km/h (50 mph).
(3) Turn the steering wheel all the way to left and right and turn
it swiftly, checking to ensure that the rear wheels steer to
the same directions as the front wheels.
REAR OIL PUMP DISCHARGE FLOW VOLUME
CHECKM37FLBA
(1) Disconnect the pressure hose from the rear oil pump and
install the special tool with a rubber hose.
(2) Place the other end of the rubber hose in a container which
permits measurement of flow rate (2-liter graduated cylin-
der).(3) Start the engine. Increase speed slowly, then hold the
indicated speed of 50 km/h (31 mph), measuring discharge
flow volume for 30 seconds.
Caution
While performing this work, continuously add fluid intothe oil reservoir.
Standard value: Approximately
1.0 liter (1.06 qts.)
(4) If the discharge flow volume is extremely high or low, the
rear oil pump should be replaced.
BALL JOINT ROTATION STARTING TORQUE
CHECKM37FECA
(1) Holding the power cylinder tie rod with a spanner, discon-
nect the tie rod and trailing arm.
(2) After swinging the ball joint stud several times, install the
stud nut, then measure the ball joint rotation starting torque
with the special tool.
Standard value: 0.5 Nm (4
in.lbs.) or less
(3) If the rotation starting torque exceeds the standard value,
replace the tie rod end.
(4) If the rotation starting torque is less than the standard
value, check that the ball joint is not loose and operates
smoothly. If not, it may be reused.
TSB Revision

4-WHEEL STEERING SYSTEM (4WS) - Power Cylinder378-712AOlOE
IlZAO2;91
3A009
Wire
SERVICE POINTS OF REMOVALM37SBM3. REMOVAL OF CROSSMEMBER MOUNTING NUT
(1) Before removing the self-locking nuts, support the
differential case with a transaxle jack.
(2) Remove the self-locking nuts.
9. REMOVAL OF TIE ROD END NUT
Secure the power cylinder on the tie rod side with a
spanner and remove the power cylinder mounting nut.
INSPECTIONM37SCM
TIR ROD SWING TORQUE INSPECTION
(1) Swing the tie rod ten times hard.
(2) Point the tie rod end down, then attach a spring balance as
shown in the illustration to measure swing resistance
(swing torque).
Standard value: 9
- 55 N (2 - 12 Ibs.)
[0.5 - 3 Nm (4 - 26 in.lbs.)l(3) If the swing resistance exceeds the standard value, replace
the tie rod.
(4) If the swing resistance is less than the standard value, the
ball joint may be reused as long as it is not loose and
operates smoothly.
POWER CYLINDER SLIDE RESISTANCE CHECK
(1) Place the piston in a neutral position.
(2) Wrap a wire around the tie rod end, then measure slide
resistance with a spring balance as shown in the illustration.
Standard value: 67 N (15
Ibs.) or less
(3) If the slide resistance exceeds the standard value,
replace,the power cylinder.
(4) If the slide resistance is less than the standard value, the
power cylinder may be reused as long as it is not loose and
slides smoothly.
SERVICE POINTS OF INSTALLATIONM37SDP911. INSTALLATION OF’ POWER CYLINDER
/ 10. POWER
CYLINDER INSTALLATION BOLTS(1) Secure the power cylinder to the crossmember.
(2) Move the power cylinder piston rod over its full stroke
to determine its neutral position.
(3) Align tie rod ends and the installation holes at trailing
arm.
TSB RevisionI

HEATERS AND MANUAL AIR CbNDlTlONER -Service Adjustment Procedures 55 17
ADJUSTMENT PROCEDURES(1) Select a quiet area for testing. Duplicate conditions as much
as possible. Switch compressor on and off several times to
clearly identify compressor noise.
To duplicate high ambient conditions (high head pressure),
restrict air flow through condenser. Install manifold gauge
set to make sure discharge pressure doesn’t exceed 2,070
kPa (300 psi).
(2) Tighten all compressor mounting bolts, clutch mounting
bolt, and compressor drive belt. Check to assure clutch coil
is tight (no rotation or wobble).
(3) Check refrigerant hoses for rubbing or interference that can
cause unusual noises.
(4) Check refrigerant charge. (See “Charging System”.)
(5) Recheck compressor noise as in Step 1.
(6) If noise still exists, loosen compressor mounting bolts and
retorque. Repeat Step 1.
(7) If noise continues, replace compressor and repeat Step 1.
POWER RELAY CHECKMBBFNAK(1) Remove the radiator fan motor relays (HI) and (LO) from the
relay box on the right of the engine compartment.
(2) Remove the radiator fan motor relay (air conditioner),
condenser fan motor relays (HI) and (LO), and
air-conditioner compressor relay from the relay box on the left
of the engine compartment.
(3) Remove the blower motor relay from the junction box.
(4) Remove the blower motor HI relay from the blower case
assembly.
(5) Check the continuity between terminals using a circuit
tester.
J Blower m.otor HI relay\2OFOO6l
IDLE-UP OPERATION CHECKM55FOAB
(1) Before inspection and adjustment set vehicle in the
following condition:
lEngine coolant temperature: 80 - 95°C (176 - 203°F)
lLights, electric cooling fan and accessories: Set to OFF
l Transaxle: Neutral (N or P for vehicles with
A/T)l Steering wheel: Straightforward
(2) Check to be sure that the idling speed becomes the
standard value when the air conditioner switch is switched
ON and the air conditioner is activated.
Standard value: 900
+ 100 rpm
NOTEThere is no necessity to make an adjustment, because the
idling speed is automatically adjusted by the ISC” system.
If, however, there occurs a deviation from the standard
value for some reason, check the ISC” system.
ISC: Idle Speed Control
1 TSB RevisionI -