Subaru Legacy 2004 Service Manual page 2750

12.General Diagnostic Table
A: INSPECTION
1. CLUTCH
Symptom
1. Clutch slippage
It is hard to perceive clutch slippage in
the early stage, but pay attention to the
following symptoms.
• Engine speeds up when shifting.
• High-speed driving is impossible; espe-
cially rapid acceleration is impossible and
vehicle speed does not increase in pro-
portion to the increase in engine speed.
• Power falls, particularly when ascend-
ing a slope, and there is a smell of burn-
ing of the clutch facing.
• Method of testing: Put the vehicle in a
stationary condition with parking brake
fully applied. Disengage the clutch and
shift the transmission gear into the 1st.
Gradually allow the clutch to engage
while gradually increasing the engine
speed. The clutch function is satisfactory
if the engine stalls. However, the clutch is
slipping if the vehicle does not start off
and the engine does not stall.
2. Clutch drags.
As a symptom of this trouble, a harsh
scratching noise develops and control
becomes quite difficult when shifting
gears. The symptom becomes more
apparent when shifting into the 1st gear.
However, because much trouble of this
sort is due to defective synchronization
mechanism, carry out the following tests.
• Method of testing: <Ref. to CL-34,
DIAGNOSTIC DIAGRAM OF CLUTCH
DRAG, INSPECTION, General Diagnos-
tic Table.>
It may be judged as insufficient disen-
gagement of clutch if any noise occurs
during this test.
3. Clutch chatters.
Clutch chattering is an unpleasant vibra-
tion to the whole body when the vehicle is
just started with clutch partially engaged.
4. Noisy clutch
Examine whether the noise is generated
when the clutch is disengaged, engaged,
or partially engaged.
General Diagnostic Table
Possible cause
(a) Clutch facing smeared by oil
(b) Worn clutch facing
(c) Deteriorated diaphragm spring
(d) Distorted pressure plate or flywheel
(e) Defective release bearing holder
(a) Worn or rusty clutch disc hub spline
(b) Excessive deflection of clutch disc
facing
(c) Stick of crankshaft pilot needle bear-
ing
(d) Cracked clutch disc facing
(e) Stuck clutch disc (smeared by oil or
water)
(a) Adhesion of oil on the facing
(b) Weak or broken damper spring
(c) Defective facing contact or excessive
disc
(d) Warped pressure plate or flywheel
(e) Loose disc rivets
(f) Loose engine mounting
(g) Improper adjustment of pitching stop-
per
(a) Broken, worn or unlubricated release
bearing
(b) Insufficient lubrication of pilot bearing
(c) Loose clutch disc hub
(d) Loose damper spring retainer
(e) Deteriorated or broken damper spring Replace clutch disc.
CL-33
CLUTCH SYSTEM
Corrective action
Replace.
Replace.
Replace.
Rectify or replace.
Rectify or replace.
Replace clutch disc.
Rectify or replace.
Replace.
Replace.
Replace.
Replace clutch disc.
Replace clutch disc.
Replace the defective clutch disc.
Rectify or replace.
Replace clutch disc.
Retighten or replace mounting.
Adjustment.
Replace the release bearing.
Replace the pilot bearing.
Replace clutch disc.
Replace clutch disc.