Mitsubishi Lancer Evolution X. Manual - part 621

CLUTCH RELEASE CYLINDER

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CLUTCH OVERHAUL

21B-7

2. Measure the rivet sink. Replace the clutch disc if it is below 

the limit.

Minimum limit: 0.3 mm (0.012 inch)

3. Check the torsion spring for play and damage. If defective, 

replace the clutch disc.

4. Place the clutch disc on the input shaft and check for sliding 

condition and play in the rotating direction. If poor sliding 
condition is evident, clean, reassemble, and recheck. 
If excessive play is evident, replace the clutch disc and/or 
input shaft.

CLUTCH RELEASE CYLINDER

DISASSEMBLY AND ASSEMBLY

M1212001500595

AKX00764AG

Rivet sink

Torsion spring

AK702336

AC

1

4

5

6

7

9

8

10

11

12

13

2

3

22 ± 2 N·m
16 ± 1 ft-lb

11 ± 1 N·m
97 ± 8 in-lb

DISASSEMBLY STEPS 

1. Cap
2. Air breather
3. Union bolt
4. Union
5. Gasket

>>B<<

6. Valve plate

>>B<<

7. Valve plate spring

8. Push rod
9. Boot

<<A>> >>A<<

10. Piston

<<A>> >>A<<

11. Piston cup
12. Conical spring
13. Release cylinder

DISASSEMBLY STEPS 

CLUTCH RELEASE CYLINDER

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CLUTCH OVERHAUL

21B-8

DISASSEMBLY SERVICE POINT

.

<<A>> PISTON / PISTON CUP REMOVAL

CAUTION

Covering with a shop towel or the like, apply compressed 
air slowly to prevent the piston from popping up and brake 
fluid from splashing.
Using compressed air, remove the piston assembly from the 
release cylinder.

ASSEMBLY SERVICE POINT

.

>>A<< PISTON CUP / PISTON INSTALLATION

1. Apply brake fluid to the entire inner surface of the release 

cylinder.

Specified brake fluid: Brake fluid DOT 3 or DOT 4

2. Apply grease to the piston and piston cups and insert the 

piston assembly into the release cylinder.

Specified grease: Rubber grease

.

AK102083

AK704100AC

AK203875 AE

Piston

Piston cup

CLUTCH RELEASE CYLINDER

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CLUTCH OVERHAUL

21B-9

>>B<< VALVE PLATE SPRING / VALVE PLATE 
INSTALLATION

Install the valve plate spring and valve plate into place with the 
large end of the spring to the valve plate side.

INSPECTION

M1212001600387

.

RELEASE CYLINDER

1. Check the bore of the release cylinder for rust, scratches or 

damage.

2. Using a cylinder gauge, measure the inside diameter of the 

release cylinder at about three positions (the deepest, 
middle and brim positions). If the clearance from the outside 
diameter of the piston exceeds the limit, replace the release 
cylinder as an assembly.

Limit: 0.15 mm (0.006 inch)

AK201696AH

Valve plate spring

Release cylinder

Valve plate

NOTES