General Diagnostic - Subaru IMPREZA 2002 Service Manual

GENERAL DIAGNOSTIC
I
MANUAL TRANSMISSION AND DIFFERENTIAL
21 .General Diagnostic
A: INSPECTION
1. MANUAL TRANSMISSION
I
Symptom
1. Gears are difficult to intermesh.
VOTE:
The cause for difficulty in shifting gears
:an be classified into two kinds: one is
malfunction of the gear shift system and
:he other is malfunction of the transmis-
sion. However, if the operation is heavy
and engagement of the gears is difficult,
jefective clutch disengagement may also
D e responsible. Check whether the clutch
s correctly functioning, before checking
the gear shift system and transmission.
2. Gear slips out.
road.
.-
Gear slips out during acceleration.
Gear slips out when coasting on rough
3. Unusual noise comes from transmis-
sion.
NOTE:
If an unusual noise is heard when the ve-
hicle is parked with its engine idling and if
the noise ceases when the clutch is disen-
gaged, it may be considered that the
noise comes from the transmission.
Possible cause
(a) Worn, damaged or burred chamfer of
internal spline of sleeve and reverse
driven gear
(b) Worn, damaged or burred chamfer of
spline of gears
(c) Worn or scratched bushinas
(d) Incorrect contact between synchro-
nizer ring and gear cone or wear
(a) Defective pitching stopper adjustment
(b) Loose engine mounting bolts
(c) Worn fork shifter, broken shifter fork
rail spring
Id) Worn or damaaed ball bearina
(e) Excessive clearance between splines
of synchronizer hub and synchronizer
sleeve
(f) Worn tooth step of synchronizer hub
(resDonsible for slipout of 3rd clear)
(9) Worn 1 st driven gear, needle bearing
and race
(h) Worn 2nd driven gear, needle bearing
and race
Ii) Worn 3rd drive aear and bushinn
(i)
Worn 4th drive gear and bushing
(k) Worn reverse idler gear and bushing
(a) Insufficient or improper lubrication
(b) Worn or damaged gears and bearings
NOTE:
If the trouble is only wear of the tooth sur-
faces, merely a high roaring noise will oc-
cur at high speeds, but if any part is
broken, rhythmical knocking sound will be
heard even at low speeds.
Remedv
~~
Replace.
Replace.
Redace.
Correct or replace.
Adjust.
Tiahten or redace.
u
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Lubricate or replace with specified oil.
Replace.
MT-84