Mitsubishi 380. Manual — part 855

ON-VEHICLE SERVICE

POWER STEERING

37-18

FLUID REPLACEMENT

M1372002100366

1. Raise and support the front wheels.
2. Disconnect the return hose connection, and then connect a

vinyl hose to the return hose, and drain the fluid into a
container.

3. Disconnect the ignition coil connectors (refer to GROUP 16,

Ignition Coil,

P.16-33

).

4. While operating the starter motor intermittently, turn the

steering wheel all the way to the left and right several times
to drain all of the fluid.

5. Connect the return hose securely, and then secure with the

clip.

6. Fill the oil reservoir with GENUINE MITSUBISHI POWER

STEERING FLUID up to the lower mark of the reservoir, and
then bleed the air.

POWER STEERING SYSTEM AIR BLEEDING

M1372002200352

Perform air bleeding procedure as necessary after replacing
the steering gear, oil pump or the steering fluid lines.
1. Raise and support the front wheels.

2. Disconnect the ignition coil connectors (Refer to GROUP 16,

Ignition Coil,

P.16-33

).

CAUTION

Perform air bleeding only while cranking the engine. Do
not perform air bleeding while the engine is running. If you
do so, air in the fluid will be increased and air bleeding will
become more difficult. During air bleeding, refill the steer-
ing fluid so that the level never falls below the lower mark
on the dipstick.
3. Turn the steering wheel all the way to the left and right five

or six times while using the starter motor to crank the engine
intermittently several times (for 15 to 20 seconds).

4. Connect the ignition coil connectors (Refer to GROUP 16,

Ignition Coil,

P.16-33

).

5. Start the engine and allow to idle.

6. Turn the steering wheel to the left and right until there are no

air bubbles in the oil reservoir.

7. Confirm that the fluid is not milky, and that the level is

between the high and low dipstick marks.

8. Confirm that there is very little change in the fluid level when

the steering wheel is turned left and right.

AC206743

RETURN
HOSE

VINYL HOSE

AB

ON-VEHICLE SERVICE

POWER STEERING

37-19

CAUTION

If the fluid level rises suddenly after the engine is stopped,
the air has not been completely bled. If air bleeding is not
complete, there will be abnormal noises from the pump
and the flow-control valve, and this condition could reduce
the life of the power steering components.
9. Confirm that the change in the fluid level is no more than 5

mm (0.2 inch) when the engine is stopped.

10.If the change of the fluid level is 5 mm (0.2 inch) or more,

the air has not been completely bled from the system. The
air bleeding procedure must be repeated.

OIL PUMP PRESSURE TEST

M1372002300337

Required Special Tools:

• MB990662: Power Steering Oil Pressure Gauge

• MB991548: Power Steering Oil Pressure Gauge Adapter

(Pump Side)

• MB991549: Power Steering Oil Pressure Gauge Adapter

(Hose Side)

1. Disconnect the pressure hose from the oil pump, and then

connect special tools MB991548, MB990662 and
MB991549.

2. Bleed air, then turn the steering wheel several times while

the vehicle is not moving so that the temperature of the fluid
rises to approximately 50

− 60°C (122 − 140°F).

3. Start the engine and idle it.

CAUTION

The pressure gauge shut-off valve must not remain closed
for more than 10 seconds.
4. Fully close the shut-off valve of the pressure gauge and

measure the oil pump relief pressure to confirm that it is
within the standard value range. Open it again immediately
after checking the pressure.

Standard value:

3.8L engine: 9.3

− 9.8 MPa (1,349 − 1,421 psi)

5. If it is not within the standard value, replace the oil pump.

6. Check whether or not the hydraulic pressure is the standard

value when no-load conditions are created by fully opening
the shut-off valve of the pressure gauge.

Standard value: 0.8

− 1.0 MPa (116 − 145 psi)

7. If it is not within the standard value, the probable cause is a

malfunction of the oil line or steering gear, so check these
parts and repair as necessary.

ACX01131

WHILE ENGINE

RUNNING

AC

FLUID LEVEL CHANGE:WITHIN 5 mm (0.2 in)

WHILE ENGINE

STOPPED

ACX01133

THERMO-

METER

RESERVOIR

ADAPTER

(MB991548)

OIL

PUMP

ADAPTER

(MB991549)

AB

SHUT-OFF VALVE

(FULLY CLOSED)

PRESSURE

GAUGE

(MB990662)

ON-VEHICLE SERVICE

POWER STEERING

37-20

8. Turn the steering wheel all the way to the left or right; then

check the retention hydraulic pressure.

Standard value:

3.8L engine: 9.3

− 9.8 MPa (1,349 − 1,421 psi)

9. If not the standard value, overhaul or replace the steering

gear. Remeasure fluid pressure.

10. Remove special tools MB991548, MB990662 and

MB991549, connect the pressure hose to the oil pump, and
then tighten the eye bolt to the specified torque.

Tightening torque: 57

± 7 N⋅m (42 ± 5 ft-lb)

11. Bleed the system (Refer to

P.37-18

).

POWER STEERING PRESSURE SWITCH CHECK

M1372007200346

Required Special Tools:

• MB990662: Power Steering Oil Pressure Gauge

• MB991548: Power Steering Oil Pressure Gauge Adapter

(Pump Side)

• MB991549: Power Steering Oil Pressure Gauge Adapter

(Hose Side)

1. Disconnect the pressure hose from the oil pump, and then

connect the special tools MB991548, MB990662 and
MB991549.

2. Bleed air, and then turn the steering wheel several times

while the vehicle is not moving so that the temperature of
the fluid rises to approximately 50

− 60°C (122 − 140°F).

3. The engine should be idling.

4. Disconnect the connector for the oil pressure switch, and

place an ohmmeter at the switch.

5. Gradually close the shut-off valve of the pressure gauge and

increase the hydraulic pressure, then check whether or not
the hydraulic pressure that activates the switch is the
standard value.

Standard value: 1.8

− 2.4 MPa (261 − 348 psi)

6. Gradually open the shut-off valve and reduce the hydraulic

pressure; then check whether or not the hydraulic pressure
that deactivates the switch is the standard value.

Standard value: 0.8

− 2.4 MPa (116 − 348 psi)

7. Remove special tools MB991548, MB990662 and

MB991549, connect the pressure hose to the oil pump, and
then tighten the eye bolt to the specified torque.

Tightening torque: 57

± 7 N⋅m (42 ± 5 ft-lb)

8. Bleed the system. (Refer to

P.37-18

).

ACX01134 AB

THERMO-

METER

ADAPTER

(MB991548)

RESERVOIR

OIL

PUMP

ADAPTER

(MB991549)

SHUT-OFF

VALVE

PRESSURE

GAUGE

(MB990662)

ON-VEHICLE SERVICE

POWER STEERING

37-21

TIE ROD END BALL JOINT DUST COVER CHECK

M1372008600284

1. Press the dust cover with your finger to check whether the

dust cover is cracked or damaged.

2. If the dust cover is cracked or damaged, replace the tie rod

end.

NOTE: If the dust cover is cracked or damaged, the ball joint
could be damaged.

STEERING COLUMN SHAFT ASSEMBLY SHOCK
ABSORBING MECHANISM CHECK

M1372013500131

• If a collision occurs or severe impact is applied to the steer-

ing wheel, the collision energy absorbing mechanism (slide
plate, ripping plate, tilt pin) may have operated. Once the
mechanism has operated, it will be inoperative even if there
is no apparent damage. Determine if the steering column
shaft can be reused by the following procedure. If the colli-
sion energy absorbing mechanism has already operated,
replace the steering column assembly.

• If any excessive radial or axial free play on the steering

wheel is found with the tilt lever in the lock position, always
check the steering column assembly.

WARNING

1.

If the vehicle continues to be driven after the colli-
sion absorbing mechanism has operated, the
steering column shaft may be damaged while driv-
ing.

2.

If there is a slack in the one-way capsule, do not
attempt to repair it. Replace the steering column
assembly.

Inspection Procedure

1. Remove the steering column covers (lower and upper).

CAUTION

Do not release the tilt lever until the steering column has
been installed to complete this inspection procedure.

2. Place the tilt lever in the locked position.

3. Loosen the two upper steering column mounting bolts by

two turns.

4. Hold the steering wheel, and then try to rock it. If there is a

radial or axial free play, replace the steering column
assembly.

AC308268 AC

SLIDE PLATE

RIPPING PLATE

TILT PIN