7E-62
1968
PONTIAC
SERVICE
MANUAL
f. Line
pressure tap plug—stripped, shy sealer
compound.
g.
Parking
pawl shaft cup plug—damaged, im-
properly
installed.
h.
Vent pipe (refer to item 5).
I.
Porous case.
4.
FRONT
END
LEAK
a.
Front
seal - damaged (check converter neck
for nicks, etc., also for pump bushing moved
forward);
garter spring missing from pump to
converter hub seal.
b. Pump attaching bolts and seals—damaged,
missing, bolts
loose.
c. Converter—leak in weld.
d.
Pump O-ring seal—damaged. Also check
pump
groove
and case bore.
e. Porous casting (pump or case).
5.
OIL COMES OUT VENT PIPE
a.
Transmission over-filled.
b. Water in oil.
c. Pump to case gasket mispositioned.
d.
Foreign material between pump and case,
or
between pump cover and body.
e. Case—porous, pump face imprope rly
machined.
f.
Pump—
shy of stock on mounting faces, por-
ous casting, breather hole plugged in pump cover.
g. Incorrect dipstick.
h.
Cut O-ring or grommet on strainer.
TURBO
HYDRA-MATIC TRANSMISSION-
VACUUM MODULATOR CHECK
1. Vacuum Diaphragm
Leak
Check
Insert
a pipe cleaner into the vacuum connector
pipe as far as possible and check for the presence
of transmission oil. If oil is found, replace the
modulator.
NOTE:
Gasoline
or water vapor may settle in the
vacuum side of the modulator. If this is found with-
out the presence of oil, the modulator should not
be
changed.
2. Atmospheric
Leak
Check
Apply
a liberal coating of soap bubble solution
(obtainable at a 5f-10£ store) to the vacuum con-
nector pipe seam, the crimped upper to lower hous-
ing seam and the threaded screw seal (Fig. 7E-174).
Using
a short piece of rubber tubing, apply air pres-
sure
to the vacuum pipe by blowing into the tube and
observe for leak bubbles. If bubbles appear, replace
the modulator.
NOTE:
Do not use any method other than human
lung
power for applying air
pressure,
as
pressures
over
6 psi may damage the modulator.
3.
Bellows Comparison
Check
Using
a comparison
gauge
(Fig. 7E-175), compare
the load of a known
good
Hydra-Matic modulator
with
the assembly in question:
a.
Install
the modulator that is known to be
acceptable on either end of the
gauge.
b.
Install
the modulator in question on the op-
posite
end of the
gauge.
c. Holding the modulators in a horizontal po-
sition, bring them
together
under pressure until
either modulator
sleeve
end just touches the line in
the center of the
gauge.
The tap between the op-
posite
modulator
sleeve
end and the
gauge
line
i—THREADED SCREW
SEAL
S
UPPER
TO
LOWER
HOUSING SEAM
-VACUUM CONNECTOR
SEAM
• ENDS
TO BE
SQUARE
WITHIN
1/64"
-1/2'^
-SCRIBED
LINE
32
.
3"
ROUND
OR
8 FLATSTOCK-
Fig.
7E-174
Cross
Section
of
Vacuum
Modulator
Fig.
7E-175 Comparison Gauge
To Next Page
Loading...
