Mitsubishi Evolution X. Manual — part 207

CRANKSHAFT AND CYLINDER BLOCK

TSB Revision

ENGINE OVERHAUL

11B-75

>>E<< CRANKSHAFT BEARING CAP /
CRANKSHAFT BEARING CAP BOLT
INSTALLATION

AK702195AD

Timing chain side

10

11

12

15

16

19

20

13

14

5

6

9

1

2

3

4

7

8

17

18

10

11

12

15

16

19

20

13

14

5

6

9

1

2

3

4

7

8

17

18

1. Install the crankshaft bearing cap with reference to the

identification mark as illustrated.

AK702196

77 mm
(3.03 in)

46 mm
(1.81 in)

AC

44 mm
(1.73 in)

23 mm
(0.91 in)

<M10>

<M8>

A

B

A

B

2. Before using the crankshaft bearing cap bolt again, carry out

the check according to the following procedure:

(1) Measure the 2 points on the outside diameter of thread

as shown in the illustration.

(2) When the difference between the measured outside

diameters is beyond the limit value, replace the
crankshaft bearing cap bolt.

Limit value

M10: 0.15 mm (0.006 inch)
M8: 0.10 mm (0.004 inch)

3. Apply engine oil to the threaded portion and seat surface of

the bolt.

4. Tighten crankshaft bearing cap bolts to the specified torque

according to the tightening order.

Specified torque

M10: 37.2

± 2.0 N⋅ m (27 ± 1 ft-lb)

M8: 9.0

± 2.0 N⋅ m (80 ± 17 in-lb)

AK703290

90˚

AC

Paint mark

Paint mark

5. Make a paint mark on the head of each bolt.
6. Make a paint mark on the bearing cap 90

° from the paint

mark made on the bolt, in the direction of tightening the bolt.

CAUTION

• When the tightening angle is smaller than the specified

tightening angle, the appropriate tightening capacity
cannot be secured.

• When the tightening angle is larger than the specified

tightening angle, remove the bolt to start from the
beginning again according to the procedure.

7. Turn each bolt 90

° in the tightening sequence specified in

step 1, and make sure that the paint marks on the bolt and
cap are aligned.

AK503375

CRANKSHAFT AND CYLINDER BLOCK

TSB Revision

ENGINE OVERHAUL

11B-76

8. Check end play of the crankshaft after installing the

crankshaft bearing cap. If the end play exceeds the limit,
replace the thrust bearing.

Standard value: 0.05

− 0.25 mm (0.002 − 0.010 inch)

Limit: 0.4 mm (0.02 inch)

INSPECTION

M1113008801767

.

CRANKSHAFT OIL CLEARANCE (PLASTIGAGE
METHOD)

Oil clearance can be easily measured by using a "plastigage."
When using a "plastigage," perform measurement in the follow-
ing procedure.
1. Fully wipe oil off the outside diameter of the crankshaft and

inside diameter of the bearing.

2. Assemble the crankshaft.

AK703296AC

Plastigage

3. Place a plastigage in length equal to the bearing width on

the journal shaft straight in alignment with the shaft center.

4. Carefully install the bearing cap and tighten the bolt

according to the main point of installation >>B<<.

5. Remove the bolt, and then carefully remove the crankshaft

bearing cap.

AK703297

6. Measure the crushed plastigage width (area most widely

crushed) using a scale printed on the plastigage bag.

Standard value:

No. 1, 2, 4, 5: 0.039

− 0.065 mm (0.0015 − 0.0026 inch)

No. 3: 0.051

− 0.077 mm (0.0020 − 0.0030 inch)

Limit: 0.10 mm (0.004 inch)

.

CRANKSHAFT AND CYLINDER BLOCK

TSB Revision

ENGINE OVERHAUL

11B-77

CYLINDER BLOCK

1. Visually check the cylinder block for scratch, rust and

corrosion. Use a flaw detecting agent to check for cracks. If
it is found faulty, repair or replace it.

AK502746

2. Measure distortion on the top surface of the cylinder block

using a straight edge and thickness gauge.
If distortion exceeds the limit, grind and repair it.
A gasket or the like must not be adhered to the top surface
of the cylinder block during measurement.

Distortion on bottom

Standard value: Within 0.05 mm (0.002 inch)
Limit: 0.2 mm (0.01 inch)
Grinding limit: 0.2 mm (0.01 inch)

3. Check the cylinder bore for scoring or seizure. If faulty,

correct (boring) or replace.

AK703729AC

45 mm

(1.78 in)

12 mm

(0.47 in)

100 mm

(3.94 in)

4. Measure the bore and cylindricity of the cylinder using a

cylinder gauge.
If the cylinder is excessively worn, repair the cylinder and
replace the piston and piston rings.
Measuring points are as shown in the illustration.

Standard value

Cylinder bore: 86 mm (3.4 inches)
Cylindricity: 0.010 mm or less (0.0004 inch)

.

BORING CYLINDERS

AK703827AB

12 mm (0.5 in)

1. Oversize pistons should be based on the largest bore

cylinder.

Size

Size mark

0.25 mm (0.010 inch)
oversize

25

NOTE: The size mark is stamped on the piston top.

2. In case of 0.25 mm (0.010 inch) oversized piston, a hole

shall be bored through the cylinder block so that the
clearance can have the standard value. The standard
measuring point for the outside piston diameter is at shown
in the illustration.

3. Based on the measured piston outside diameter (O.D.),

calculate the boring finish dimension.

Boring finish dimension = Piston O.D. + 0.03

− 0.05 mm

(0.001

− 0.002 inch) <Clearance between piston O.D.

and cylinder>

− 0.02 mm (0.001 inch) <honing margin>

4. Bore each cylinders to the calculated boring finish

dimension.

CRANKSHAFT AND CYLINDER BLOCK

TSB Revision

ENGINE OVERHAUL

11B-78

CAUTION

To prevent distortion caused by heat increased during bor-
ing, bore the cylinders in the following order: No.2, No.1,
No.3.
5. Hone the cylinders to the final finish dimension (piston O.D.

+ piston-to-cylinder clearance).

6. Check the clearance between the pistons and cylinders.

Standard value: 0.03

− 0.05 mm (0.001 − 0.002 inch)

NOTE: When boring cylinders, finish all of four cylinders to
the same oversize. Do not bore only one cylinder to an over-
size.