1973 OPEL GT-R automatic transmission

DIAGNOSIS
SEQUENCE
1. Check and correct oil level. Refer to Specifications
for checking and refill procedures.
2. Check and correct vacuum line and fittings.
3. Check and correct manual linkage.
4. Road test car using all selective ranges, noting
when discrepancies in operation occur.
5. If engine performances indicates an engine tuneup
is required, this should be performed before road
testing is completed or transmission correction at-
tempted. Poor engine performance can result in
rough shifting or other malfunctions.
CHECKING PROCEDURESBefore diagnosis of any transmission complaint is
attempted, there must be an understanding of oil
checking procedure and what appearance the oil
should have. Many times a transmission malfunction
can be traced to low oil level, improper reading of
dipstick, or oil appearances; therefore, a careful anal-
ysis of the condition of oil and the level may elimi-
nate needless repairs.
When checking oil level in the Opel Three Speed
Automatic Transmission, the procedure outlined in
Specifications should be followed to obtain the most
accurate reading.
Also when the dipstick is removed, it should be noted
whether the oil is devoid of air bubbles or not. Oil
with air bubbles gives an indication of an air leak in
the suction lines, which can cause erractic operation
and slippage. Water in the oil imparts a milky, pink
cast to the oil and can cause spewing.
EXTERNAL OIL LEAKS
Determining source of oil leakBefore attempting to correct an oil leak, the actual
source of the leak must be determined. In many
cases, the source of the leak can be deceiving due to
“wind flow” around the engine and transmission.
The suspected area should be wiped clear of all oil
before inspecting for the source of the leak. Red dyeAUTOMATIC TRANSMISSION 7C- 81
is used in the transmission oil at the assembly plant
and will indicate if the oil leak is from the transmis-
sion.The use of a “Black Light” to locate the point at
which the oil is leaking is 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-engine or transmission.
Oil leaks around the engine and transmission are
generally carried toward the rear of the car by 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 a
leak, proceed as follows:
1. Degrease underside of transmission.
2. Road test to get unit at operating temperature.
3. Inspect for leak with engine running.
4. With engine off, check for oil leaks due to the
raised oil level caused by drain back.
Case Porosity RepairOpel Three-Speed Automatic Transmission external
oil leaks caused by case porosity can be successfully
repaired with the transmission in the car by using the
following recommended procedures:
1. Road test and bring the transmission to operating
temperature, approximately 180 degrees F.
2. Raise car on a hoist or jack stand, engine running,
and locate source of oil leak. Check for oil leaks in
low, drive, and reverse.
3. Shut engine off and thoroughly clean area to be
repaired with a suitable cleaning solvent and a
brush- air dry. A clean, dry soldering acid brush can
be used to clean the area and also to apply the epoxy
cement.
4. Using instructions of the manufacturer, mix a suf-
ficient amount of epoxy, BUICK Group 0.423, Part
No. 1360016, or equivalent, to make the repair. Ob-
serve cautions of manufacturer in handling.
5. While the transmission case is still HOT, apply the
epoxy to the area to be repaired. Make certain the
area to be repaired is fully covered.
6. Allow cement to cure for 3 hours before starting
engine.
7. Road test and check for leaks.

7C- 821973 OPEL SERVICE MANUALAUTOMATIC TRANSMISSION TROUBLE
DIAGNOSIS CHART
Condition
CEllE.e
Concerns Transmission Oil1. Low oil level.a) Oil coming out of oil tiller tube.
b) External oil leak.
c) Failed vacuum modulator.
2. Oil coming out of oil filler
tube.a) Oil level too high.
b) Coolant in transmission oil.
c) External vent clogged with mud.
d) Leak in oil pump suction circuit.
3. External oil leaks in the area
of the torque converter housing.a) Leaking torque converter.
b) Converter housing seal.
c) Sealing washers under converter
housing to case bolts.
d) Sealing washers under converter
housing to pump bolts.
e) Converter housing to case seal.
fj Loose attaching bolts on front of
transmission.
4. External oil leaks in the area
of transmission case and extension.a) Shifter shaft seal.
b) Extension seal.
c) Oil pan gasket.
d) Extension to case gasket.
e) Vacuum modulator gasket.
f) Drain plug gasket.
g) Cooler line fittings.
h) Oil tiller tube seal ring.
i) Detent cable seal ring.
j) Line pressure gauge connection.
5. Low oil pressure.a) Low oil level.
b) Clogged suction screen.
c) Leak in oil pump suction circuit.
d) Leak in oil pressure circuit.
e) Priming valve stuck.
t) Pressure regulator valve malfunction.
g) Sealing ball in valve body dropped out.
6. High oil pressure.a) Modulator vacuum line leaky orinteruupted.
b) Failed vacuum modulator.
c) Leak in any part of engine or
accessory vacuum system.
d) Pressure regulator valve malfunction.
7. Excessrive smoke coming from
exhaust.a) Failed vacuum modulator.
b) Oil from vent valve or leak on hot
exhaust pipe.

AUTOMATIC TRANSMISSION 7C- 83
ConditionCause
Starting
1. No starting in any driverange.a) Low oil level.
b) Clogged suction screen.
c) Manual valve linkage or inner trans-
mission selector lever disconnected.
d) Input shaft broken.e) Pressure regulator valve stuck in open
position. -0 Failed oil pump.
2. No starting in any drive range
for a time. Driving possible only
after repeatedly moving selector
lever to and fro.Manual valve position does not coincide
with valve body channels:
a) Selector lever shaft retaining
pin dropped out.
b) Connecting rod to manual valve
shifting.
c) Selector lever shaft nut loose.
3. No starting after shifting
lever from “P” to “D”, “S”, or “L”
(inadequate engine acceleration).a) Parking
paw1 does not disengage.
4. Sudden starting only after
increase of engine RPM.a) Band servo piston jamming.
b) Low oil level.
c) Oil pump defective.
d) Oil screen missing.
e) Sealing ball in valve body dropped out
5. Heavy jerking when starting.a) Low oil pressure.
b) Wrong modulator valve.
c) Pressure regulator valve stuck.
d) Sealing ball in valve body dropped out.
6. No starting in “D” or “S”
range, but in “L” and “R” range.a) Input sprag installed backwards.
b) Input sprag failure.
7. No starting in “D” or “S” and
“L” (proper driving in “R”; see
also point 9).a) Band worn, does not grip.
b) Band servo piston jamming.
c) Excessive leak in band servo.
d) Parking
paw1 does not disengage.

AUTOMATIC TRANSMISSION 7C- 87
HYDRAULIC PRESSURE CHECK SHIFT POINTS
SPECIFICATIONSHYDRAULIC PRESSURE CHECKSNOTE: ON REPLACING PLUG, TOROUE TO 6.7 LEFT.
D65
4. After pressure gage and hose is install&, replace rear
crossmembers65
and side bolts and proceed with pressure checking procedure.L80NOTE: PRESSURES ARE OFF OF THE SERVO APPLY.OPERATING CONDITIONS
Detent Downshift Possible

AUTOMATIC TRANSMISSION 7C- 89
DRIVESERVO
LINE
REVERSEI
,NTERMEDlATE\T
SERVO APPLYMODULATOR OR
Figure 7C75 Valve Body Top

AUTOMATIC TRANSMISSION 7C- 91
MAINTENANCE AND ADJUSTMENTS
DETENT CABLE REPLACEMENT AND
ADJUSTMENT
The reliability of the detent bowden control cable is
greatly dependent upon the proper adjustment of the
wire whenever installation is being made. It is impor-
tant to remember that the free end of the wire is not
kinked, as individual strands will break due to the
continuous bending during operation. To avoid this
situation, it is important that the bowden control
cable be properly installed. Although replacement
and adjustment procedures on various models are
identical, the location of the upper, or throttle, end
of the detent cable may vary. For proper model iden-
tification, see Figures
7C-61, 7C-62, 7C-63, and 7C-
64.Figure JC-79 Opel 1900 and Manta
Figure
7~80 Opel 1900 and MantaFigure JC-81 GT Models
Figure JC-93 GT Models
Removal
I. Detach retainer at detent cable to accelerator link-
age.2. Loosen rear transmission crossmember from body
and remove right side bolt. See Figure
7C-84, Callout
” A ”3. Insert block of wood between floor pan and right
rear corner of transmission to expose detent cable
bracket at transmission. See Figure
7C-85.4. Unscrew detent cable connecting retainer from
transmission and pull cable out of transmission. See
Figure
7C-86.

AUTOMATIC TRANSMISSION 7C- 93
(on Manta models, turn adjuster) until ball end of
cable rests firmly against lever.
2. At this point, measure length of exposed detent
inner cable. Depress accelerator pedal fu/fy, and
again measure inner cable. If correctly adjusted, de-
tent cable should move approximately 3/S inch.
Servicing Selector Lever1. Unscrew console from floor panel, on small con-
sole remove three (3) attaching screws and
on large
console remove four (4) screws. The fourth screw is
accessible after removal of ash tray. See Figure 7C-
88.Figure
7C-88Figure
7C-892. Unplug cigar lighter and lamps from console and
remO”e co”sole.
3. From below vehicle, remove selector rod from
intermediate selector lever.
4. Remove neutral start switch (A) and remove sup-
port housing attaching bolts. See Figure
7C-89.5. Remove support housing and, from the underside
of support housing, remove three (3) support attach-
ing bolts. See Figure
7C-90.Figure
7C-906. Remove intermediate selector lever (B) from shaft
and remove assembly from support housing. See Fig-
ure 7C-92.7GB2
Figure
7C.92

7C. 941973 OPEL SERVICE MANUAL
7. Drive out retaining pin and shaft and remove se-
lector detent. See Figure 7C-93.Figure
7C-93Figure
7C-94 - Exploded View of Selector Lever
8. To replace bowden cable in selector lever, knock
off selector handle, remove screws from clamping
piece and pull knob.
9. Remove pull knob and bowden cable, taking care
not to lose lock bolt bushing, thrust springs, ‘and
washer.
10. Place thrust spring, bushing, washer, and thrust
spring onto new bowden cable, in that order, and
insert cable into selector lever.
1 I. Slide pull onto selector lever and clamping piece
onto cable.
12. Heat up new selector lever handle in water to 176
degrees F. and push onto selector lever.
13. Set dimension between pull knob and selector
lever handle at
.4 inch and tighten set screws.
14. Lubricate selector lever detent and shaft. Install
detent, align selector lever with support, install shaft,
and drive in new retaining pin.
15. Install assembly to support housing and install
intermediate selector lever.
16. Install assembly to vehicle and install neutral
start switch.
17. Install console lights and cigar lighter connec-
tions to console and install console to vehicle.
18. Lubricate and connect selector rod to intermedi-
ate selector lever and adjust according to Figure 7C-
198.
MAJOR REPAIRREMOVAL AND INSTALLATION OF AUTOMATIC
TRANSMISSION
Removal
- Opel 1900 and Manta
I. Disconnect battery.
2. Remove dipstick.
3. Remove screws from fan shroud.
4. Remove 2 upper starter bolts.
5. Raise car and provide support for front and rear
and drain oil.
6. Remove bolts from engine support brackets, both
sides. Let brackets hang by front bolts. See Figure7c-105.
7. Remove flywheel cover pan.
8. Remove exhaust pipe from manifold and unhook
rubber tailpipe suspension.
9. Remove drive shaft. Do not misplace thrust spring
in spline.
10. Disconnect cooler lines at flexible hoses.
II. Detach both stabilizer supports from
crossmem-ber to body supports and loosen stabilizer bolts in
lower control arms. See Figure X-84, Callout “B”,