Subaru XT 1988 Service Manual page 406

2-10
CLUTCH
TROUBLESHOOTING
Condition
1. Clutch
slippage
2. Clutch
drags
Possible cause and testing Corrective action
It is hard to perceive clutch slippage in the early stage, but pay attention to the following symptoms.
(a) Engine revs up when shifting.
(b) High speed driving is impossible; especially rapid acceleration impossible and vehicle speed does
not increase in proportion to an increase in engine speed.
(c) Power falls, particularly when ascending a slope, and there is a smell of burning of the clutch facing .
• Method of testing:
Put the car in stationary condition with parking brake fully applied. Disengage the clutch and shift
the transmission gear into the first. 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 car does not start off and the engine does not stall.
(a)
No clutch pedal play Readjust.
(b)
No release lever end play Readjust.
(c)
Clutch facing smeared by oil Replace.
(d)
Worn clutch facing Replace.
(e) Deteriorated diaphragm spring Replace.
(f)
Distorted pressure plate or flywheel Correct or replace.
(g)
Defective release bearing holder Correct or replace.
(h)
Defective pedal and cable system Correct or replace.
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 first gear. However,
because much trouble of this sort is due to defective synchronization mechanism, carry out the test as
described after.
• Method of testing:
Refer to diagnostic diagram on page after.
It may be judged as insufficient disengagement of clutch if any noise occurs during this test.
(a) Excessive clutch pedal play
(b) Excessive clutch release lever play
(c) Worn or rusty clutch disc hub spline
(d) Excessive deflection of clutch disc facing
(e) Seized crankshaft pilot needle bearing
(f) Malfunction of pedal and cable system
(g) Cracked clutch disc facing
(h) Sticked clutch disc (smeared by oil or water)
10
Readjust.
Readjust.
Replace clutch disc.
Correct or replace.
Replace.
Correct or replace.
Replace.
Replace.