Shift Valve; Governor Assembly - Buick LeSabre 1965 Service Manual

5 - 1 5 0 TROUBLE DIAGNOSIS
SUPER TURBINE "400'
broken, on pump cover; leak in
feed circuits; pump to case gasket
mispositioned or damaged. Piston
ball check stuck or missing.
F. Low sprag assembly
1. Sprag assembled backwards,
sprags inoperative (rolled over).
IL 1-2 Shift - Full Throttle Only
A. Detent switch
1. Sticking or defective (may stick
in cold or wet weather).
B. Detent solenoid
1. Loose
2. Gasket leaking
3. Sticks open
C. Control valve assembly
1. Valve body gaskets - leaking,
damaged, incorrectly installed.
2. Detent valve train.
3. 3-2 valve stuck.
D. Case assembly
1. Porosity
IE. First Speed Only, No. 1-2
Shift
A. Governor assembly
1. Governor valve sticking.
2. Driven gear loose, damaged
or worn, (check for pin in case
and length of pin showing); also
check output shaft drive gear for
nicks or rough finish, if driven
gear shows damage.
B. Control valve assembly
1. 1-2 shift valve train stuck
closed.
2. Governor f e e d c h a n n e l s
blocked, leaking, pipes out of
position.
3. Valve body gaskets - leaking,
damaged, incorrectly installed.
C. Case
1. I n t e r m e d i a t e clutch plug
leaking or blown out.
2. Porosity between channels.
3. Governor feed channel blocked.
D. Intermediate clutch
1. Case center support - oil rings
missing, broken, defective.
2. Clutch piston seals - missing,
improperly assembled, cut.
IV. First and Second Speeds Only,
No 2-3 Shift
A. Detent solenoid
1. Stuck open (Detent shifts only -
the 2-3 shift would occur at very
high speeds being interpreted as
no 2-3 shift.)
B. Detent Switch
C. Control valve assembly
1. 2-3 valve train stuck.
2. Valve body gaskets - leaking,
damaged, incorrectly installed.
D. Direct clutch
1. Case center support - oil rings
missing, broken, defective.
2. Clutch piston seals - missing,
improperly assembled, cut, piston
ball check stuck or missing.
V. Drive In Neutral
A. Manual linkage
1. Maladjusted
B. Forward clutch
1. Clutch does not release - (this
condition will also cause "No
Reverse
;;
).
VI. No Drive in Reverse, or Slips
in Reverse - (Install Pressure
Gauge)
A. Low oil level
B. Manual linkage
C. Oil pressure - (refer to oil
pressure table for specifications)
1. Vacuum modulator assembly -
defective.
2. Vacuum m o d u l a t o r valve -
sticking.
3. Restricted strainer or leak at
intake pipe, or intake "O" ring.
4. Pump assembly - regulator or
boost valve sticking.
D. Control valve assembly
1. Valve body gaskets - leaking,
damaged, incorrectly installed.
(Other malfunctions may also be
indicated.)
2. Low R e v e r s e ball check -
missing from case (this will also
cause no overrun braking in Lo
Range).
3. 2-3 Valve train stuck open (this
will also cause 1-3 upshift in
Drive Range).
4. Reverse feed passage - miss-
ing (refer to Shop Manual for
location); a l s o c h e c k c a s e
passages.
E. Rear servo and accumulator
1. Servo piston seal ring, dam-
aged or missing.
2. Short band apply pin (this may
also cause no overrun braking or
slips in overrun braking - Lo
Range). Refer to Shop Manual for
pin selection procedure.
F. Reverse or low band
1. Burnt, loose lining, apply pin
or anchor pins not engaged, band
broken.
G. Direct clutch
1. Outer s e a l d a m a g e d or
missing.
2. Clutch plates burnt - may be
caused by stuck ball check in
piston.
H. Forward clutch
1. Clutch does not release (will
also cause Drive in Neutral).
VIL Slips in All Ranges, Slips on
Start~ (Install pressure gauge)
A. Oil level
B. Oil pressure (refer to oil
pressure table for specifications).
1. Vacuum modulator defective.
2. V a c u u m m o d u l a t o r valve
sticking.