Mitsubishi 380. Manual - part 450

ROCKER ARMS AND CAMSHAFT

ENGINE OVERHAUL <3.8L ENGINE>

11B-26

>>D<< CAMSHAFT OIL SEAL INSTALLATION

Use special tools MD998713 and MB991559 to install the cam-
shaft oil seal.

INSPECTION

M1113005500463

.

ROCKER ARM SHAFT

Check the rocker arm mounting areas of the rocker arm shafts 
for wear or damage. Replace as necessary.

.

ROCKER ARM

1. Check the roller surface and replace the rocker arm if 

recesses, damage or heat seizure is observed.

2. Check roller rotation and replace the rocker arm if uneven 

rotation or roller backlash of the roller is observed.

3. Check the inside diameter and replace the rocker arm if 

damage or seizure is observed.

.

CAMSHAFT

1. Check the camshaft bearing journals for damage and 

binding. If the journals are binding, check the cylinder head 
for damage. Also check the cylinder head for clogged oil 
holes.

2. Check the tooth surface of the distributor drive gear teeth of 

the camshaft and replace if abnormal wear is evident.

AKX00615

<RIGHT BANK SIDE>

MD998713

AB

AKX00639

<LEFT BANK SIDE>

MB991559

AB

MD998713

AKX00723

ROLLER TIP

AB

ROCKER ARMS AND CAMSHAFT

ENGINE OVERHAUL <3.8L ENGINE>

11B-27

3. Check the cam surface for abnormal wear and damage and 

replace if necessary. Also measure the cam height and 
replace if out of minimum limit.

Standard value:

Intake 37.39 mm (1.472 inches)
Exhaust 37.71 mm (1.485 inches)

Minimum limit:

Intake 36.89 mm (1.452 inches)
Exhaust 37.21 mm (1.465 inches)

.

LASH ADJUSTERS

CAUTION

• The lash adjusters are precision-engineered mecha-

nisms. Do not allow them to become contaminated by 
dirt or other foreign substances.

• Do not attempt to disassemble the lash adjusters.
• Use only fresh diesel fuel to clean the lash adjusters.

1. Prepare three containers and approximately 5 dm

3

 (30.5 

quart) of diesel fuel. Into each container, pour enough diesel 
fuel to completely cover a lash adjuster when it is standing 
upright. Then, perform the following steps with each lash 
adjuster.

2. Place the lash adjuster in container A and clean its outside 

surface.

NOTE: Use a nylon brush if deposits are hard to remove.

CAUTION

The steel ball spring is extremely weak, so the lash 
adjuster's functionality may be lost if the air bleed wire is 
pushed in hard.
3. While gently pushing down the internal steel ball using wire 

[0.5 mm (0.020 inch) in diameter] or special tool MD998442, 
move the plunger through five to ten strokes until it slides 
smoothly. In addition to eliminating stiffness in the plunger, 
this operation will remove dirty oil.

NOTE: If the plunger remains stiff or the mechanism 
appears otherwise abnormal, replace the lash adjuster.

AKX00685

AKX00625

OUTSIDE

CLEANING

INSIDE

CLEANING

FILLING

DIESEL FUEL

A

B

C

AB

AKX00626

DIESEL

FUEL

AB

AK202680

AK202680

DIESEL FUEL

MD998442

AE

ROCKER ARMS AND CAMSHAFT

ENGINE OVERHAUL <3.8L ENGINE>

11B-28

4. Remove the lash adjuster from the container. Then, push 

down the steel ball gently and push the plunger to eliminate 
diesel fuel from the pressure chamber.

CAUTION

The steel ball spring is extremely weak, so the lash 
adjuster's functionality may be lost if the air bleed wire is 
pushed in hard.
5. Place the lash adjuster in container B. Then, gently push 

down the internal steel ball using a wire [0.5 mm (0.020 
inch) in diameter] or special tool MD998442 and move the 
plunger through five to ten strokes until it slides smoothly. 
This operation will clean the lash adjuster's pressure 
chamber.

6. Remove the lash adjuster from the container. Then, push 

down the steel ball gently and push the plunger to eliminate 
diesel fuel from the pressure chamber.

CAUTION

Do not use container C for cleaning. If cleaning is per-
formed in container C, foreign matter could enter the pres-
sure chamber when the chamber is filled with diesel fuel.
7. Place the lash adjuster in container C. Then, gently push 

down the internal steel ball using a wire [0.5 mm (0.020 
inch) in diameter] or special tool MD998442.

8. Stand the lash adjuster with its plunger at the top, then push 

the plunger downward firmly until it moves through its 
greatest possible stroke. Return the plunger slowly, then 
release the steel ball and allow the pressure chamber to fill 
with diesel fuel.

AK202681

DIESEL FUEL

MD998442

AD

AK202680

AK202680

DIESEL FUEL

MD998442

AE

AK202681

DIESEL FUEL

MD998442

AD

AK202682

DIESEL FUEL

MD998442

AD

AK202683

DIESEL FUEL

MD998442

AD

CYLINDER HEAD AND VALVES

ENGINE OVERHAUL <3.8L ENGINE>

11B-29

9. Remove the lash adjuster from the container, then stand the 

lash adjuster with its plunger at the top. Push the plunger 
firmly and check that it does not move. 

NOTE: If the lash adjuster contracts or moves, repeat steps 
7 through 9 again to fill it with diesel fuel completely. 
Replace the lash adjuster if it still contracts or moves after 
performing these steps.

10.Stand the lash adjuster upright to prevent diesel fuel from 

spilling out. Do not allow the lash adjuster to become 
contaminated by dirt or other foreign matter. Install the lash 
adjuster onto the engine as soon as possible.

CYLINDER HEAD AND VALVES

REMOVAL AND INSTALLATION

M1113006900527

AKX00627

AK304296AB

4

12

21

5

6

7

13

14

17

9

11

16

19

10

18

22

20

8

15

108 ± 5 N·m

80 ± 4 ft-lb

    0 N·m

    0 in-lb

108 ± 5 N·m

80 ± 4 ft-lb

1

2

→

→

APPLY ENGINE OIL

TO ALL MOVING

PARTS BEFORE

INSTALLATION.

3

REMOVAL STEPS

<<A>> >>D<<

1.

CYLINDER HEAD BOLT

2.

WASHER

3.

CYLINDER HEAD ASSEMBLY

4.

CYLINDER HEAD GASKET

<<B>> >>C<<

5.

RETAINER LOCK

6.

VALVE SPRING RETAINER

>>B<<

7.

VALVE SPRING

8.

INLET VALVE 

REMOVAL STEPS (Continued)