Pontiac FIREBIRD 1972 Service Manual page 900

7E-10 1972 PONTIAC SERVICE MANUAL
d. Intermediate clutch piston seals damaged or
missing.
of the leak can be deceiving due to wind flow around the
engine and transmission.
The suspected area should be wiped clean of all oil before
inspecting for the source of the leak. Red dye is used in
the transmission oil at the assembly plant and will indicate
if the oil leak is from the transmission.
e. Center support bolt loose.
f. Low line pressure (see LOW LINE PRESSURE
above).
g. Intermediate clutch cup plug in case missing.
The use of a black light to identify the oil at the source of
leak is also helpful. Comparing the oil from the leak to
that on the engine or transmission dipstick (when viewed
by black light) will determine the source of the leak.
h. Transmission case valve body face not flat or
porosity between channels.
i. Manual valve bent and center land not ground
properly.
Oil leaks around the engine and transmission are generally
carried toward the rear of the car by the air stream. For
example, a transmission oil filler tube-to-case leak will
sometimes appear as a leak at the rear of the transmission.
In determining the source of an oil leak, it is most helpful
to keep the engine running.
3. Direct Clutch:
a. Restricted orifice in vacuum line to modulator
(poor vacuum response).
POSSIBLE POINTS OF OIL LEAKS
b. Check ball in clutch piston damaged, stuck or
missing.
TRANSMISSION OIL PAN
c. Defective modulator bellows.
1. Attaching bolts not correctly torqued.
d. Center support bolt loose (bolt may be tight in
support but not holding support tight to the case).
2. Improperly installed or damaged pan gasket.
3. Oil pan gasket mounting face not flat.
e. Center support oil rings or grooves damaged or
missing.
CASE EXTENSION
1. Attaching bolts not correctly torqued.
f. Clutch piston cracked, seals damaged or missing.
2. Rear seal damaged or improperly installed.
g. Front and rear servo pistons and/or seals da-
maged.
3. Extension-to-case gasket damaged or improperly in-
stalled.
h. 3-2 valve, 3-2 valve spring or 3-2 spacer pin in-
stalled in wrong location in 3-2 valve train bore.
4. Porous casting
*.
CASE
i. Manual valve bent and center land not ground
properly.
1. Filler pipe O-ring seal damaged or missing; misposi-
tion of filler pipe bracket to engine
-
loading one side
of O-ring.
j.
Transmission case valve body not flat or porosity
between channels. 2. Modulator O-ring seal damaged or improperly in-
stalled.
k. Intermediate sprag installed backwards.
3. Governor cover, gasket and bolts damaged, loose;
case face leak.
4. In addition, burned clutch plates can be caused by
incorrect usage of clutch plates. Also, anti-freeze in
transmission fluid can cause severe damage, such as
large pieces of clutch plate material peeling off.
4. Speedometer gear O-ring damaged.
5. Manual shaft seal damaged, improperly installed.
6. Line pressure tap plug stripped, shy sealer com-
pound.
OIL LEAKS
Before attempting to correct an oil leak, the actual source
of the leak must be determined. In many cases, the source
7. Parking pawl shaft cup plug damaged, improperly
installed.