Mitsubishi Montero Sport (2004+). Manual - part 139

CYLINDER HEAD AND VALVES

TSB Revision

ENGINE OVERHAUL

11B-31

INSPECTION

M1113007000022

.

CYLINDER HEAD
1. Check the cylinder head gasket surface for flatness by using 

a straightedge in the directions of A through G shown in the 
illustration.

Standard value: 0.03 mm (0.0012 inch) 
Limit: 0.2 mm (0.007 inch)

2. If the service limit is exceeded, correct to meet the 

specification.

Grinding limit: *0.2 mm (0.007 inch)

3.  *If the service limit is exceeded, correct to meet the 

specification.

Cylinder head height (specification when new):

120 mm (4.7 inches)

.

VALVE
1. Check the valve face for correct contact. If incorrect, reface 

using a valve refacer. The valve should make a uniform 
contact with the seat at the center of the valve face.

2. If the margin exceeds the service minimum limit, replace the 

valve.

Standard value:

<Intake> 1.0 mm (0.04 inch)
<Exhaust> 1.2 mm (0.05 inch)

Minimum limit:

<Intake> 0.5 mm (0.02 inch)
<Exhaust> 0.7 mm (0.03 inch)

3. Measure the valve's total length. If the measurement is less 

than specified, replace the valve.

Standard value:

<Intake> 112.30 mm (4.421 inches)
<Exhaust> 114.11 mm (4.493 inches)

Minimum limit:

<Intake> 111.80 mm (4.402 inches)
<Exhaust> 113.61 mm (4.473 inches)

.

VALVE SPRINGS
1. Measure the free height of the spring and, if it is smaller than 

the minimum limit, replace the spring.

Standard value: 51.0 mm (2.01 inches)
Minimum limit: 50.0 mm (1.97 inches)

2. Measure the squareness of the spring and, if the limit is 

exceeded, replace the spring.

Standard value: 2

° or less

Limit: 4

°

AKX00733

AKX00619

MARGIN

VALVE SEAT 
CONTACT

AB

AKX00624

AKX00607

2˚

FREE
HEIGHT

AB

CYLINDER HEAD AND VALVES

TSB Revision

ENGINE OVERHAUL

11B-32

.

VALVE GUIDES
Measure the clearance between the valve guide and valve 
stem. If the limit is exceeded, replace the valve guide, valve, or 
both.

Standard value:

<Intake> 0.02 

− 0.05 mm (0.0008 − 0.0019 inch)

<Exhaust> 0.04 

− 0.07 mm (0.0016 − 0.0027 inch)

Limit:

<Intake> 0.10 mm (0.003 inch)
<Exhaust> 0.15 mm (0.005 inch)

.

VALVE SEAT
Assemble the valve, then measure the valve stem projection 
between the end of the valve stem and the spring seating sur-
face. If the measurement exceeds the specified limit, replace 
the valve seat.

Standard value: 49.30 mm (1.941 inches)
Limit: 49.80 mm (1.960 inches)

.

VALVE SEAT RECONDITIONING PROCEDURE

CAUTION

Before correcting the valve seat, check the clearance 
between the valve guide and valve and, if necessary, 
replace the valve guide.
1. Using the special tool or a seat grinder, correct to obtain the 

specified seat width and angle.

2. After correcting the valve seat, lap the valve and valve seat 

using lapping compound. Then, check the valve stem 
projection.

.

VALVE SEAT REPLACEMENT PROCEDURE

CAUTION

Before replacing the valve seat, check the valve guide and, 
if necessary, replace the valve guide.
1. Cut the valve seat from the inside to thin the wall thickness. 

Then, remove the valve seat.

AKX00714

VALVE 
GUIDE

STEM OUTSIDE 
DIAMETER

GUIDE INSIDE DIAMETER

AB

AKX00695

SPRING SEATING
SURFACE

VALVE STEM END

VALVE STEM
PROJECTION

AB

AKX00717

0.9 – 1.3 mm
(0.04 – 0.05 in)

65˚

45˚

30˚

AB

AKX00610

0.5 – 1 mm 
(0.020 – 0.039 in)

0.5 – 1 mm (0.020 – 0.039 in)

CUT
AWAY

AB

CYLINDER HEAD AND VALVES

TSB Revision

ENGINE OVERHAUL

11B-33

2. Rebore the valve seat hole in the cylinder head to a selected 

oversize valve seat diameter.

Seat ring hole diameter:

Intake valve

0.3 oversize 34.30 

− 34.33 mm (1.3504 − 1.3516 

inches)

0.6 oversize 34.60 

− 34.63 mm (1.3622 − 1.3634 

inches)

Exhaust valve

0.3 oversize 31.80 

− 32.83 mm (1.2520 − 1.2531 

inches)

0.6 oversize 32.10 

− 32.13 mm (1.2638 − 1.2650 

inches)

3. Before fitting the valve seat, either heat the cylinder head up 

to approximately 250

°C (482°F) or cool the valve seat in 

liquid nitrogen, to prevent the cylinder head bore from 
galling.

4. Using a valve seat cutter, correct the valve seat to the 

specified width and angle. Using a valve seat cutter, correct 
the valve seat to the specified width and angle. See "VALVE 
SEAT RECONDITIONING PROCEDURE" on the previous 
page.

.

VALVE GUIDE REPLACEMENT PROCEDURE
1. Remove the snap ring from the exhaust valve guide.
2. Using a press, remove the valve guide toward the cylinder 

head gasket surface.

CAUTION

Do not install a valve guide of the same size again.
3. Re bore the valve guide hole of the cylinder head so that it 

fits the press-fitted oversize valve guide.

Valve guide hole diameter:

0.05 oversize 11.05 

− 11.07 mm (0.4350 − 0.4358 inch)

0.25 oversize 11.25 

− 11.27 mm (0.4429 − 0.4437 inch)

0.50 oversize 11.50 

− 11.52 mm (0.4528 − 0.4535 inch)

4. Install the new snap ring into the groove of exhaust valve 

guide.

5. Press-fit the valve guide until it protrudes 14 mm (0.55 inch) 

from the cylinder head top surface as shown in the 
illustration.
NOTE: When press-fitting the valve guide, work from the 
cylinder head top surface.
NOTE: After installing the valve guides, insert new valves in 
them to check for sliding condition.

AKX00611

HEIGHT OF 
SEAT RING

OVERSIZE DIAMETER

AB

AKX00712

REMOVAL

INSTALLATION

PRESS

PRESS

PUSH ROD

VALVE 
GUIDE

VALVE 
GUIDE

AB

AKX00727

14 mm 
(0.55 in)

AB

OIL PAN AND OIL PUMP

TSB Revision

ENGINE OVERHAUL

11B-34

OIL PAN AND OIL PUMP

REMOVAL AND INSTALLATION

M1113008100419

AK000437

2

3

4

5

6

7

8

9

10

12

14

15

16

17

18

19

20

11

23 ± 3 N·m
17 ± 2 ft-lb
(M8 BOLT)

39 ± 5 N·m
29 ± 4 ft-lb

19 ± 3 N·m
14 ± 2 ft-lb

44 ± 5 N·m
33 ± 4 ft-lb

9.0 ± 1.0 N·m
80 ± 9 in-lb 

14 ± 1 N·m
124 ± 9 in-lb

10 ± 2 N·m
89 ± 18 in-lb 

11 ± 1 N·m
97 ± 9 in-lb

11 ± 1N·m
97 ± 9 in-lb

AC

APPLY ENGINE OIL
TO ALL MOVING
PARTS BEFORE
INSTALLATION.

41 ± 8 N·m
30 ± 6 ft-lb
(M10 BOLT)

21

10 ± 2 N·m
89 ± 18 in-lb

23 ± 3 N·m
17 ± 2 ft-lb
(M8 BOLT)

9.0 ± 3.0 N·m
80 ± 27 in-lb

11 ± 1N·m
97 ± 9 in-lb

1

9.0 ± 3.0 N·m
80 ± 27 in-lb

13

REMOVAL STEPS

>>H<<

1. OIL PRESSURE SWITCH

>>G<<

2. OIL FILTER
3. OIL FILTER BRACKET
4. OIL FILTER BRACKET GASKET
5. DRAIN PLUG

>>F<<

6. DRAIN PLUG GASKET

<<A>> >>E<<

7. LOWER OIL PAN

<<B>> >>D<<

8. UPPER OIL PAN
9. COVER
10. BAFFLE PLATE
11. OIL SCREEN

12. OIL SCREEN GASKET
13. PLUG
14. RELIEF SPRING
15. RELIEF PLUNGER

>>C<<

16. CRANKSHAFT OIL SEAL

>>B<<

17. OIL PUMP CASE
18. O-RING
19. OIL PUMP COVER

<<C>> >>A<<

20. OIL PUMP OUTER ROTOR

<<C>> >>A<<

21. OIL PUMP INNER ROTOR

REMOVAL STEPS (Continued)