Pontiac tempest 1968 Service Manual page 536

T W O SPEED A U T O M A T I C TRANSMISSION
7F-35
I . Porous castings.
4. Leak at Front of Transmission
a. Front pump seal leaks.
(1) Seal l i p cut. Check converter hub, etc.
(2) Bushing moved and damaged. Oil return
hole plugged.
(3) No o i l return hole.
b. Front pump attaching bolts loose or damaged
or missing.
c. Front pump housing O-ring damaged or cut.
d. Converter leak in weld area.
e. Porous casting (pump).
5. Oil Comes Out Vent Pipe
a. Transmission over-filled.
b„ Water i n o i l .
c. Foreign material between pump and case or
between pump cover and body.
d. Case - porous near converter bosses. Front
pump cover or housing o i l channels shy of stock
near breather.
e. Pump to case gasket mispositioned.
WO DRIVE IN ANY SELECTOR POSITION
1. Check o i l level.
2* Check o i l pressure.
3 . Check manual shift linkage adjustment.
4. Check internal linkage.
5. Check for defective pressure regulator valve.
6. Check for pressure regulator valve retaining
ring out of groove.
7. Check for defective front pump.
ERRATIC OPERATION AND SLIPPAGE
(Light to Medium Acceleration)
1. Check strainer and suction pipe assembly for
leaks.
2. Check suction pipe O - r i n g .
3 . Low o i l level.
4. Check for defective modulator.
EXCESSIVE SLIP OR ENGINE FLARE ON
COASTING TO A STOP WHEN CORNERING
1. Check engine Idle.
2. Check for suction leak.
3 . Check low band adjustment.
4. Check for proper modulator can assembly.
NO REVERSE
1. Check reverse clutch piston seals.
2. Check freedom of reverse clutch piston.
3 . Check for open feed lines to reverse clutch.
HARSH NEUTRAL TO DRIVE SHIFT AT IDLE
1. Check engine idle speed.
2. Check vacuum line connections.
3 . Check for loose
or broken engine mounts.
NO UPSHIFT
1. Check freedom of shift valve and detent valve.
2. Check for plugged orifice in detent valve.
3 . Check for open detent solenoid and loose at­
taching bolts.
4. Check for plug i n front pump cover assembly.
5. Check clutch piston seals.
6. Check for broken clutch piston o i l seal rings.
7. Check clutch lines in front pump cover and
stator shaft assembly.
8. Check governor for failed pinion or stuck valve.
LONG SHIFT TIME-SHIFT DOES NOT HAVE
POSITIVE ENGAGEMENT
1. Check engine idle.
2. Check for suction leak.
3 . Check low band adjustment.
4. Check for proper modulator can assembly.
5. Check for defective modulator can—no bellows
load.