1973 OPEL GT-R light

7C- 541973 OPEL SERVICE MANUAL
Figure 7C-38 1 2 Shift Valve
To prevent a “hunting” condition of the shift valve,
modulator pressure supply to the second spool of
control valve is cut off as the shift valve opens line
pressure to the second clutch. The oil in this pocket
is exhausted out through the detent passage. An ad-
ditional force keeping the valve in an “upshifted”
position is obtained by line pressure acting on the
larger diameter second spool of the shift valve. Be-
cause of this, even though the governor pressure
might be maintained at a constant pressure after the
valve upshifts, a higher modulator pressure is re-
quired to cause the valve to downshift.
If the accelerator is depressed to the point where the
detent spring force is felt, the vacuum will drop and
the modulator pressure will increase. If the spring
force plus the modulator pressure acting against the
end spool of the shift control valve is great enough
to overcome the governor and line pressure acting on
the shift valve, a “part throttle” forced downshift
will occur. If not, the transmission will remain in the
higher gear.
If the accelerator is depressed through the detent, the
detent valve supplies detent regulator pressure to all
three spools of the shift control valve, a higher down-
shifting force is obtained as compared to the part
throttle condition. Because of this, a “through
detent” forced downshift can be obtained at a speed
higher than for the “part throttle” condition. How-
ever, there is still a limiting speed at which a
“through detent” forced downshift will occur.
If the selector lever is placed in “Manual Low”, line
pressure is supplied directly to the spring pocket
between the valves. Since line pressure can never be
less than governor pressure, the force established by
line pressure on the shift valve plus the spring forcewill move the shift valve to a downshifted position
regardless of car speed.
2 3
,Shift Valve and 3 - 2 Control Valve
The function and operation of the 2 3 Shift and
Shift Control Valves is the same as for the
I 2 valve
except as described below. See Figure
7C-39.The downshifted position establishes “second” gear,
and the upshifted position establishes “third” or
“high” gear.
~ZND CLUTCH*
-I.Figure
7C-39 2 3 Shift Valve and 3 2 Control Valve
Modulator pressure is supplied to the end spool of
the 2
- 3 control valve through the 3 - 2 control valve.
When the shift valve moves to the upshifted position,
line pressure is introduced to the third clutch circuit.
The third clutch circuit also directs pressure to the
end spool of the 3
- 2 control valve.
At light throttle conditions, third clutch pressure
acting on the end of the 3
- 2 control valve moves the
valve against the spring and the force established by
the modulator pressure. This exhausts the modulator
pressure from behind the end spool of the 2
- 3
control valve and the spring is the only remaining
force acting on the shift valve to produce a down-
shift. In this condition, it is not possible to obtain a
“part throttle” forced downshift.
If the accelerator is depressed far enough to cause a
substantial drop in vacuum, the increased modulator
pressure on the 3
- 2 control valve plus the spring will
overc,ome the force of the third clutch pressure. This
feeds modulator pressure back to the 2
- 3 control
valve and a “part throttle” forced downshift will
occur. As with the 1 2 shift valve, there is a limiting
speed at which this can occur.
When the selector lever is placed in “Second”, line
pressure is directed to the spring pocket between the
2
- 3 Shift and Shift Control Valves and the shift

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.

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”,

7C-1021973 OPEL SERVICE MANUAL
Figure 7C-120Figure 7C-122
Figure 7C-12 1
2. Remove modulator valve and sleeve from trans-
mission case.
Removal of Detent Valve Assembly
This operation can be performed with transmission
in vehicle
1. Remove spring pin by pulling upward with pliers.
2. Lightly tap detent valve assembly from front of
case and remove detent valve, sleeve, spring, and
spring seat from rear of easel See Figure 7C-122,Removal of Extension Housing
This operation can be performed with transmission
in vehicle
1. Remove bolt holding speedometer driven gear
housing retainer and carefully remove retainer and
pull speedometer driven gear assembly from exten-
sion housing. See Figure
7C-123.Figure
7C- 123
2. Remove the seven attaching bolts from extension
housing to case.

AUTOMATIC TRANSMISSION 7C-105
Figure 7C-133thrust bearing and race from case by pulling straight
out. See Figure
7C-134.Figure
7C-135Figure
7C-1344. Remove needle thrust bearing and race from rear
of case. See Figure
7C-135.5. Remove low band by slightly compressing band
and pulling straight out. See Figure
7C-137.6. If necessary to remove case vent, install new case
vent. Do not attempt to reinstall old vent.
Disassembly, Inspection and Reassembly of
Converter Housing, Oil Pump and Reverse Clutch1. Remove second clutch assembly from oil pump
shaft. See Figure
7C-138.

712.1081973 OPEL SERVICE MANUALCHSJ
351. RETAINING PIN
72. PRESSURE REGULATOR BOOST VALVE SLEEVE
3. PRESSURE REGVLATOR BOOST VALVE
4. PRESSURE REGULATOR VALVE SPRING SEAT
5. PRESSURE REGULATOR VALVE SPRING
6. PRESSURE REGULATOR VALVE
7. OIL PUMP BODY
8. OIL PUMP PRIMING VALVE, SPRING 8 SPRING SEAT
16. Remove reverse clutch piston.
17. Remove priming valve from oil pump body by
lightly tapping with a drift through the hole at the
rear of oil pump. (Only if diagnosis requires removal
or if excessive dirt has passed through transmission.)
18. Pressure regulator and boost valve may be
removed by using a pari of wire cutters to remove the
retaining pin. Due to the difficulty of removing the
retaining pin, it is not recommended that the pres-
sure regulator valve and boost valve be disassembled
during overhaul, unless it was determined by oil
pressure checks to have been malfunctioning prior to
tear down.
19. Remove pressure regulator boost valve sleeve,
spring, pressure regulator valve and two washers. See
Figure
7C-147.20. Inspect and if necessary replace the oil pump hub
bushing by threading a 3/4” standard pipe tap such
as tool J-23130-5 into bushing. See Figure
7C-148.Figure 7C-148

AUTOMATIC TRANSMISSION 7C-129
4. Install reverse clutch cushion plate (wave washer)2. Insert guide pin into oil pump for alignment of
into case.converter housing and lower housing onto pump.Determining Selective Washer Size
1. Place gauging tool J-23085 on case flange andagainst input shaft. See Figure
7C-215.3. Install new oil seal washers on converter housing
to oil pump bolts, and loosely install bolts into con-
verter housing.
4. Use convkrter housing to oil pump aligning tool J-23082 to align converter housing to pump. See Fig-
ure
7C-216. Tool should bottom on oil pump gear.
Figure 7C-2 152. Loosen thumb screw on tool to allow inner shaft
to drop on second clutch drum hub.
3. Tighten thumb screw and remove tool J-23085.
4. Place selective washer removed from transmission
against inner shaft of tool J-23085. Selective washer
should be flush with top face of shaft. If not flush,
select next larger or smaller washer until correct size
is obtained. The washer selected should be exactly
flush or slightly below inner shaft for correct end
play in transmission. Selective washer removed from
transmission may be oil soaked and discolored.
CObX
ID
Yellow
Blue
Red
BVSNIl
GPX3”
Black
Thickness,070.,074,076.,080
.08 l-.085,086.,090,091.,095
,097.,101
Installation of Converter Housing, Oil Pump and
Reverse Clutch Assembly1. Turn case so that bottom of transmission is facing
upward.
1. Install oil pump wear plate onto oil pump.2. Slide governor hub along output shaft and seat
Figure 7C-2 165. Tighten the five bolts. Torque to
13-17 Ibs. ft. and
remove aligning tool l-23082.
6. Install new converter housing to case rubber oil
seal.7. Install new pump flange gasket.
8. Place selective washer, previously determined,
onto the oil pump shaft and retain with petroleum
jelly (unmedicated).
9. Install two guide pins in case and lower converter
housing and oil pump into case. See Figure
7C-217.10. Bolt converter housing to case using new oil seal
washers on all seven bolts. Torque to 13-17 lbs. ft.
I I. Check for correct assembly by turning input shaft
by hand.
Installation of Governor Assembly