Mitsubishi 380. Manual — part 853

POWER STEERING DIAGNOSIS

POWER STEERING

37-10

INSPECTION PROCEDURE 9: Vibration

NOTE: A slight vibration may be felt when the stationary steer-
ing effort is made due to the condition of the road surface. To
check whether the vibration actually exists or not, test-drive the
vehicle on a dry concrete or asphalt surface. A very slight
amount of vibration is not a malfunction.

DIAGNOSIS

STEP1. Check the tyres for out-of-balance.

Q: Is the check result OK?

YES : Go to Step 2.
NO : Balance the tyres (Refer to GROUP 31, Wheel and

Tyre Diagnosis

− Wheel Balance Accuracy

P.31-3

).

And then go to Step 4.

STEP 2. Check the fluid level.
(1) Park the vehicle on a flat, level surface, and then start the

engine.

(2) Turn the steering wheel several times to raise the

temperature of the fluid to approximately 50

− 60°C (122 −

140

°F).

(3) With the engine running, turn the wheel all the way to the

left and right several times.

(4) Check the fluid in the oil reservoir for foaming or milkiness.

Check the difference of the fluid level when the engine is
stopped, and while it is running.

Q: Is the check result OK?

YES : Go to Step 3.
NO : Bleed the air (Refer to

P.37-18

). And then go to Step

4 .

STEP 3. Check the steering gear for damage.

Q: Is there damage?

YES : Repair or replace the part. And then go to Step 4.
NO : Go to Step 4.

STEP 4. Retest the system.
Confirm that there is no steering wheel vibration.

Q: Is there vibration?

YES : Repeat from Step 1.
NO : The procedure is complete.

ACX01131

WHILE ENGINE

RUNNING

WHILE ENGINE

STOPPED

AB

FLUID FLUCTUATION

POWER STEERING DIAGNOSIS

POWER STEERING

37-11

INSPECTION PROCEDURE 10: Oil Leakage from Hose Connection

DIAGNOSIS

STEP 1. Check for loosening of the
pressure/return tube flare nut.

Q: Is the flare nut loose?

YES :

Tighten it to 15

± 3 N⋅m (11 ± 2 ft-lb). And

then go to Step 3.

NO :

Go to Step 2.

STEP 2. Check the hose connection and the
clamp installation.
Refer to

P.37-45

.

Q: Are they correct?

YES :

Go to Step 3.

NO :

Correct hose connection and/or clamp
installation. And then go to Step 3.

STEP 3. Retest the system.
Check that no oil is leaking.

Q: Is there oil leakage?

YES :

Repeat from Step 1.

NO :

The procedure is complete.

INSPECTION PROCEDURE 11: Oil Leakage from Hose Assembly

DIAGNOSIS

STEP 1. Check the hose for damage or clogging.

Q: Is the hose damaged or clogged?

YES :

Repair or replace it. And then go to Step 2.

NO :

Go to Step 2.

STEP 2. Retest the system.
Check that no oil is leaking.

Q: Is there oil leakage?

YES :

Repeat from Step 1.

NO :

The procedure is complete.

INSPECTION PROCEDURE 12: Oil Leakage from Oil Reservoir

DIAGNOSIS

STEP 1. Check the oil reservoir for damage.

Q: Is there damage?

YES :

Repair or replace it. And then go to Step 3.

NO :

Go to Step 2.

STEP 2. Check for overflowing.

Q: Is there oil overflowing from the reservoir?

YES :

Adjust fluid level. And then go to Step 3.

NO :

Go to Step 3.

STEP 3. Retest the system.

Q: Is there oil leakage?

YES :

Repeat from Step 1.

NO :

The procedure is complete.

POWER STEERING DIAGNOSIS

POWER STEERING

37-12

INSPECTION PROCEDURE 13: Oil Leakage from Oil Pump

DIAGNOSIS

STEP 1. Check the oil pump body for damage.

Q: Is there damage?

YES :

Replace the part. And then go to Step 3.

NO :

Go to Step 2.

STEP 2. Check the O-ring or oil seal for damage.

Q: Is there damage?

YES :

Replace the part. And then go to Step 3.

NO :

Go to Step 3.

STEP 3. Retest the system.
Check that no oil is leaking.

Q: Is there oil leakage?

YES :

Repeat from Step 1.

NO :

The procedure is complete.

INSPECTION PROCEDURE 14: Oil Leakage from Steering Gear

DIAGNOSIS

STEP 1. Check the steering gear housing for
damage.

Q: Is there damage?

YES :

Replace the part. And then go to Step 2.

NO :

Go to Step 2.

STEP 2. Retest the system.
Check that no oil is leaking.

Q: Is there oil leakage?

YES :

Repeat from Step 1.

NO :

The procedure is complete.

SPECIAL TOOLS

POWER STEERING

37-13

SPECIAL TOOLS

M1372000600387

TOOL

TOOL NUMBER
AND NAME

SUPERSESSION APPLICATION

MB991897
Ball joint remover

MB991113-01,
MB990635-01 or
General service
tool

Knuckle and tie rod end ball joint
disconnection

NOTE: Steering linkage puller
(MB990635 or MB991113) is also
available to disconnect knuckle and
tie rod end ball joint.

MB990326
Preload socket

General service
tool

Tie rod end ball joint breakaway
torque check

MB991548
Power steering oil
pressure gauge
adapter (Pump
side)

MB991548-01

Oil pump pressure test

MB991549
Power steering oil
pressure gauge
adapter (Hose
side)

MB991549-01

MB990662
Power steering oil
pressure gauge

MB990662-01

AC106827

MB990326

MB991548

MB991549

MB990662