Spacer-Control Valve Assy. (Typical) - Pontiac TRANS AM 1977 Service Manual

7A4-8 1977 PONTIAC SERVICE MANUAL
MOD O I L
OF MOD
RND TO F SERVO
3RD CL. EX.
MOD T O
2-3 DR O I L TO F SERVO
REV O I L T O 3RD
REV 3 R D C L
382 1
Fig. 7A4-8 Spacer-Control Valve Assy. (Typical)
3. FILTER
A. BLOCKED OR RESTRICTED.
B. "0" RING ON INTAKE PIPE AND/OR
GROMMET OMITTED OR DAMAGED.
C. SPLIT OR LEAKING INTAKE PIPE.
D. WRONG FILTER ASSEMBLY.
4. PUMP
A. PRESSURE REGULATOR OR BOOST VALVE
STUCK.
B. GEAR CLEARANCE, DAMAGED, WORN
(PUMP WILL BECOME DAMAGED I F DRIVE GEAR
IS INSTALLED BACKWARDS OR IF CONVERTER
PILOT DOES NOT ENTER CRANKSHAFT FREELY).
C. PUMP TO CASE GASKET MISPOSITIONED.
D. PUMP BODY AND/OR COVER MACHINING
ERROR OR SCORING OF PUMP GEAR POCKET.
E. MISMATCH PUMP COVEWPUMP BODY
TYPES.
5. INTERNAL CIRCUIT LEAKS
A. FORWARD CLUTCH LEAK (PRESSURE
NORMAL IN NEUTRAL AND REVERSE-PRESSURE
LOW IN DRIVE):
1. CHECK PUMP RINGS FOR DAMAGE.
2. CHECK FORWARD CLUTCH SEALS FOR
DAMAGE.
3. CHECK TURBINE SHAFT JOURNALS FOR
DISTRESS.
4. CHECK STATOR SHAFT BUSHINGS FOR
DAMAGE.
B. DIRECT CLUTCH LEAK (PRESSURE
NORMAL IN NEUTRAL, LOW, SUPER AND DRIVE-
PRESSURE LOW IN REVERSE):
1. CHECK CENTER SUPPORT OIL SEAL RINGS
FOR DAMAGE.
2. CHECK DIRECT CLUTCH OUTER SEAL FOR
DAMAGE.
3. CHECK REAR SERVO AND FRONT ACCUM.
PISTONS AND RINGS FOR DAMAGE OR MISSING.
6. CASE ASSEMBLY
A. POROSITY IN INTAKE BORE AREA.
B. CHECK CASE FOR INTERMEDIATE CLUTCH
PLUG LEAK OR BLOWN OUT (SEE FIG. 7A4- 13 1).
C. LOW LINE PRESSURE IN REVERSE OR IF LO-
REVERSE CHECK BALL MISPOSITIONED OR
MISSING (THIS WILL CAUSE NO REVERSE AND NO
OVERRUN BRAKING IN LO RANGE).
THERE IS NOT APPROVED WAY FOR
CHECKING OR CLEANING THE FILTER. I F THE
FILTER IS SUSPECTED OF BEING PLUGGED OR
RESTRICTED, IT MUST BE REPLACED.
HIGH LINE PRESSURE
1. VACUUM LEAK
A. FULL LEAK, VACUUM LINE
DISCONNECTED.
B. PARTIAL LEAK IN LINE FROM ENGINE TO
MODULATOR.
C. IMPROPER ENGINE VACUUM.
D. VACUUM OPERATED ACCESSORY LEAK
(HOSES, VACUUM ADVANCE, ETC.).
2. DAMAGED MODULATOR
A. STUCK VALVE.
B. WATER IN MODULATOR.