Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Service manual — part 459

CL-11

Clutch Disc and Cover

CLUTCH SYSTEM

2. Clutch Disc and Cover

A: REMOVAL

1) Remove the transmission assembly from the ve-

hicle. <Ref. to 6MT-31, REMOVAL, Manual Trans-

mission Assembly.> <Ref. to 5MT-23, REMOVAL,

Manual Transmission Assembly.>

2) Attach the ST on the flywheel.

ST 499747100

CLUTCH DISC GUIDE

3) Remove the clutch cover and clutch disc.
NOTE:

• Take care not to allow oil to touch the clutch disc

face.

• Do not disassemble the clutch cover or clutch

disc.

B: INSTALLATION

1) Insert the ST into the clutch disc and attach to

the flywheel by inserting the ST end into pilot bear-

ing.
NOTE:

When installing the clutch disc, be careful to attach

in the correct direction.

ST 499747100

CLUTCH DISC GUIDE

2) Install the clutch cover to the flywheel and tight-

en the bolts to the specified torque.
NOTE:

• When installing a clutch cover to the flywheel,

position the clutch cover so that the spacing be-

tween the unbalance marks (paint mark) on the fly-

wheel and clutch cover is 120° or more apart. (The

unbalance mark indicates the direction of residual

unbalance.)

• Temporarily tighten the bolts by hand. Each bolt

should be tightened to the specified torque in a

crisscross order.
Tightening torque:

16 N·m (1.6 kgf-m, 11.8 ft-lb)

• STI model

(A) Clutch cover

(A) Flywheel side

CL-00011

( A )

S T

CL-00208

(A)

ST

(A) Unbalance mark (paint)

CL-00792

( A )

S T

( 2 )

( 5 )

( 3 ) ( 1 )

( 6 )

( 4 )

( 7 )

( 8 )

( 9 )

CL-12

Clutch Disc and Cover

CLUTCH SYSTEM

• Except for STI model

3) Remove the ST.

ST 499747100

CLUTCH DISC GUIDE

4) Install the transmission assembly. <Ref. to 6MT-

33, INSTALLATION, Manual Transmission Assem-

bly.> <Ref. to 5MT-26, INSTALLATION, Manual

Transmission Assembly.>

C: INSPECTION

1. CLUTCH DISC

1) Facing wear

Measure the depth from the facing surface to the

rivet head. Replace if the face is worn locally or

worn down to less than the specified value.
Depth to rivet head:

Limit of sinking

0.8 mm (0.031 in)

NOTE:

Do not wash the clutch disc with any type of clean-

ing fluid.

2) Hardened facing

Replace the clutch disc.

3) Oil soakage on facing

Replace the clutch disc and inspect the transmis-

sion front oil seal, transmission case mating sur-

face, engine rear oil seal and other locations for oil

leakage.

4) Deflection on facing

If deflection exceeds the specified value at the out-

er circumference of the facing, replace the clutch

disc.

ST 499747100

CLUTCH DISC GUIDE

Limit for deflection:

STI model

0.7 mm (0.028 in) at R = 115 mm (4.53 in)

Except for STI model

0.7 mm (0.028 in) at R = 110 mm (4.33 in)

(A) Unbalance mark (paint)

CL-00013

( A )

S T

( 2 )

( 5 )

( 3 )

( 1 )

( 6 )

( 4 )

CL-00014

(A) Clutch facing

CL-00015

(A)

CL-00016

S T

CL-13

Clutch Disc and Cover

CLUTCH SYSTEM

5) If there is spline wear, loose rivets, failed damper

springs, etc., replace the clutch disc.

2. CLUTCH COVER

NOTE:

Visually check the following items without disas-

sembling, and replace or repair if defective.

1) Loose thrust rivet

2) Damaged or worn bearing contact area at the

center of diaphragm spring

3) Damaged or worn disc contact surface of the

pressure plate

4) Loose strap plate installation area

5) Worn diaphragm sliding area

(A) Spline
(B) Rivet

(C) Damper spring

(A) Thrust rivet
(B) Diaphragm spring

(A) Pressure plate
(B) Strap plate

CL-00017

CL-00018

( A )

( B )

CL-00176

(A)

(B)

CL-14

Flywheel

CLUTCH SYSTEM

3. Flywheel

A: REMOVAL

1) Remove the transmission assembly. <Ref. to

6MT-31, REMOVAL, Manual Transmission As-

sembly.> <Ref. to 5MT-23, REMOVAL, Manual

Transmission Assembly.>

2) Remove the clutch cover and clutch disc. <Ref.

to CL-11, REMOVAL, Clutch Disc and Cover.>

3) Using the ST, remove the flywheel.

ST 498497100

CRANKSHAFT STOPPER

B: INSTALLATION

1) Install the flywheel and ST.

ST 498497100

CRANKSHAFT STOPPER

2) Tighten the flywheel mounting bolts to the spec-

ified torque.
NOTE:

Tighten the flywheel attachment bolts gradually.

Each bolt should be tightened to the specified

torque in crisscross order.
Tightening torque:

75 N·m (7.6 kgf-m, 55.3 ft-lb)

3) Install the clutch disc and cover. <Ref. to CL-11,

INSTALLATION, Clutch Disc and Cover.>

4) Install the transmission assembly. <Ref. to 6MT-

33, INSTALLATION, Manual Transmission Assem-

bly.> <Ref. to 5MT-26, INSTALLATION, Manual

Transmission Assembly.>

C: INSPECTION

CAUTION:

Because the center bearing is grease-sealed

and is a non-lubrication type, do not wash with

gasoline or solvents.

1) If there is damage or defectiveness in the facing

sliding surface or ring gear, replace the flywheel.

2) Smoothness of rotation

Rotate the ball bearing while applying pressure in

the thrust direction.

3) If noise or excessive play is noted, replace the

flywheel.

(A) Flywheel

CL-00019

S T

( A )

CL-00801

S T

(A) Flywheel
(B) Ring gear

CL-00021

( 1 )

( 2 )

( 3 )

( 4 )

( 5 )

( 6 )

( 7 )

( 8 )

CL-00022

( B )

( A )