712.501973 OPEL SERVICE MANUAL
3. Detent pressure regulator valve.
4. 1 - 2 Accumulator valve.
5. Governor.
B. Selector valves (manually and hydraulically con-
trolled).
I. Manual valve.
2. Detent valve.
3. 1
- 2 Shift valve.
4. 2
- 3 Shift valve.
5. 3
- 2 Downshift control valve.
6. Manual low and reverse control valve.
7. Boost control valve.
C. Timing Valves.
1. Low speed downshift timing valve.
2. High speed downshift timing valve.
3. Second clutch orifice valve.
D. Accumulators.
1. 1
- 2 Accumulator.
2. Low servo piston.
Main Pressure Regulator ValveOil pressure from the pump is delivered to the “line”
port of the main regulator valve. See Figure
7C-30.The port is connected through a damping orifice, to
the regulator port at the end of the regulator valve.
As the pressure in this port increases, it moves the
valve against the spring force until the second spool
of the. valve just opens to the “line” port. This per-
mits the pump pressure to be by- passed into the
pump suction passage. Therefore, the valve will regu-
late at
a’ fixed minimum pressure as determined by
the spring force, and all excess pump delivery will be
by-passed back into the pump suction passage.
In moving from the “bottomed” to the regulating
position, the valve also opens line pressure to the
converter feed passage. This oil is directed to and
through the
cow&x, through the oil cooler, to the
gear box lubrication system, then back to the sump.
In order to provide the required capacity in the band
and clutches, it is desirable to have a variable line
pressure that will increase with engine torque. This
PRESSURE’REGULATORY7c30Figure 7C-30 Pressure Regulator Valve
is accomplished by introducing a “modulator” pres-
sure on the end of the boost valve. The force of the
boost valve acts against the end of the regulator valve
and increases the line pressure above the base pres-
sure as established by the spring force. By introduc-
ing line pressure to the stepped area between the
spools of the boost valve, an additional pressure in-
crease over and above that described above is ob-
tained.
The regulated line pressure is then fed to:
Manual valve.
Modulator valve
Detent pressure regulator valve
Modulator Valve and Vacuum ModulatorLine pressure is directed to the second port of the
modulator valve. See Figure
7C-31. This pressure
passes between the spools of the valve and into the
modulator port. The modulator port is connected to
the regulating port at the end of the valve through a
damping orifice. As the pressure in the regulating
port incieases, it moves the valve outward against
the spring force of the modulator assembly until the
end spool just closes the line port. If excess pressure
has built up in the regulating port the valve will
continue to move till the second spool just opens to
the exhaust port. In other words, the valve tends to
regulate between the line and exhaust ports.
Even though the modulator spring force may be con-
stant, thereby causing the modulator valve to regu-
late at a fixed pressure, the pressure requirements
AUTOMATIC TRANSMISSION7c-51VACUUM MODULATOR7c31
Figure 7C-31 Vacuum Modulator and Modulator Valve
decrease as car speed increases. For this reason, gov-
ernor pressure (which is a function of car speed) is
directed to the area between the two different diame-
ter spools at the outboard end of the valve. As gover-
nor pressure increases, it creates an outward force on
the modulator valve and in effect reduces the spring
force of the modulator assembly.
The modulator assembly consists of two chambers
separated by a diaphragm. The chamber toward the
valve is open to atmosphere and the other chamber
is connected to engine vacuum. The vacwm cham-
ber also contains a spring. When there is no vacuum
(0” of mercury), the full spring force bears against
the diaphragm and is transmitted to the valve
through a plunger. This is the spring force which
establishes the regulated pressure of the modulator
valve. As the vacuum in the outer chamber increases,
an outward force is created on the diaphragm which
cancels out some of the spring force. This continues
up to
16” of vacuum, at which point the diaphragm
force cancels out the spring force and the modulator
pressure becomes zero.
In summary, the following indicates the function of
the total modulator system in combination with the
pressure regulator system.
In addition, higher car speeds will produce a some-
what lower modulator and line pressure for any
given vacuum by virtue of the governor pressure
acting on the modulator valve.
Engine
TorqueLow
High
VacuumHigh
Low
Modulator
PreSSWe
LowHigh
LineLOW
HighModulator pressure is then directed to:
Pressure regulator boost valve.
I - 2.Shift control.
2
- 3-Shift control valve by way of the 3 - 2 control
valve.Detent Valve.
I - 2 Accumulator Va!ve.
Low Speed Downshift Timing Valve.
Detent Pressure Regulator ValveThe regulating action of the Detent Pressure Regula-
tor Valve is essentially the same as for the Modulator
Valve, except that it regulates a constant pressure.
See Figure
7C-32. The feed port, regulating port and
exhaust port all function in the same manner as the
Modulator Valve. Since the force set up by the pres-
sure in the regulating port acts only against a
fixedspring force, the resulting detent pressure is con-
stant. The detent regulator pressure is directed to the
Detent Valve and to the Manual Low and Reverse
Control Valve.
DET. PRESS.,REG.
i7G3-2
Figure 7C-32 Detent Pressure Regulator Valve
l-2 Accumulator ValveThe
I 2 Accumulator Valve, Figure 7C-33, is used
to establish a desired pressure to ultimately control
the rate of apply of the second clutch during a
I to
2 upshift. Here again, the regulating action is essen-
tially the same as for the Modulator Valve or Detent
Pressure Regulator Valve.
7C- 521973 OPEL SERVICE MANUAL
CCUMULATOR
DRIVE:--7633
Figure 7C-33 1
- 2 Accumulator Valve
The ports and spools operate as previously described.
However, for increased engine torque, it is necessary
to increase the accumulator pressure. This is accom-
plished by introducing modulator pressure to the
small end of the 1-2 accumulator valve. As the
modulator pressure increases, it adds to the spring
force and increases the l-2 accumulator pressure.
The 1-2 accumulator pressure is fed to the bottom
(spring loaded side) of the 1-2 accumulator piston.
The Governor is mounted on the output shaft and
contains two interconnected regulating valves See
Figure
7C-34. Its purpose is to supply an oil pressure
5 8I. GOVERNOR SECONDARY VALVE6
SPRING RETAINER
2. GOVERNOR SECONDARY VALVE SPRING
3. GOVERNOR SECONDARY VALVE
4. GOVERNOR PRIMARY VALVE
5. GOVERNOR BODY6. ROLL PINIC~VFigure 7C-34 Governor Assemblythat is a function of output shaft or car speed. Line
pressure is supplied to the governor from the Manual
Valve (to be covered later). The governor operates on
the principle of centrifugal force. That is, as an object
spins off center at changing speeds, its outward force
is a function of the rotating speed.
Line pressure is directed to the outer-most port of the
secondary valve. The secondary spring holds the
valve in an outward position so that the outer spool
of the valve is open to “line”. As the line pressure
builds up between the spools, it exerts a force on the
larger diameter inner spool to start counteracting the
spring. When the hydraulic force is large enough, it
moves the valve inward against the spring force until
the outer spool closes the line port. If the pressure
between the spools still creates a force larger than the
spring force, the valve will continue to move inward
until the excess pressure opens to the exhaust port.
The valve then regulates between the line and ex-
haust port.
A fixed governor pressure in the secondary valve has
now been established with no rotation of the output
shaft. As the governor begins to rotate, the outward
force (due to the weight of the secondary valve) is
added to the force of the spring. Therefore, as the
speed increases, the outward force and in turn the
secondary valve pressure increases.
The secondary valve pressure is directed to the feed
port of the primary valve. With no rotation of the
governor, the pressure acts against the large inner
spool and forces it to open to the exhaust port. Since
there is no spring force on the primary valve, it will
continue to keep the feed port closed and the exhaust
port open. The final governor pressure is then zero.
As the governor begins to rotate, the weight of the
primary valve creates an outward force working
against the oil pressure. The pressure in the primary
valve port now increases as a function of speed. This
continues up to the speed where the outward force
finally holds the primary valve outward, keeping the
feed port open.
In summary, at zero speed, the governor pressure is
zero. As the speed increases, the governor pressure
will increase as dictated by the primary valve until
the speed is great enough to hold the primary valve
all the way out. At speeds above this point, the gover-
nor pressure is established by the secondary valve.
Governor pressure is then directed to:
Modulator Valve.
1 - Two Shift Valve.
2
- Three Shift Valve.
3 High Speed Downshift Timing Valve.
7c. 581973 OPEL SERVICE MANUAL
a. NEUTRAL & PARK
- ENGINE RUNNING
Neutral
- Engine Running
Reverse Clutch. Released
Second Clutch. Released
Sprag
- LockedThird Clutch
- Released
Low Band .
.ReleasedIn neutral, the low band and all clutches are released. With this condition, no member of the planetary gear set is
held and there is no reaction member. All gears are free to rotate around their own axis and no torque is trans-
mitted to the planet carrier assembly and output shaft.
Park
- Engine Running
The same power flow conditions in the neutral position are in effect in the park position. Additionally, mechan-
ical linkage actuates a parking pawl which engages with the
splines in the periphery of the governor assembly.
Since the governor assembly is splinad to the output shaft, the parking pawl holds the output shaft locked to the
extension, preventing the vehicle from rolling.7ci48
Figure 7C-48 Neutral and Park Engine Running
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- 95
12. Place suitable jack under transmission and
remove transmission support bolts.
13. Lower transmission enough to remove detent
cable and modulator vacuum line.
14. Remove speedometer cable.
15. Remove selector lever.
16. Mark flywheel and converter for reassembly in
same position, and remove converter to flywheel
bolts. See Figure 7C-106.17. Remove converter housing to engine bolts and
tiller tube.
18. Pry transmission loose from engine.
19. Keep rear of transmission lower than front to
prevent converter from falling and install converter
holding fixture J-21366. Lower transmission and
move to bench.
Installation. Opel 1900 and Manta1. Assemble transmission to suitable jack and raise
transmission into position. Rotate converter to per-
mit coupling of fly wheel and converter with original
relationship. Remove J-21366.
2. Install tiller tube and converter housing to engine
block bolts. Torque to 35 lb. ft. DO NOT over
torque.
3. Install flywheel to converter bolts. Torque to 30 lb.
ft.4. Install detent cable to transmission.
5. Connect oil cooler lines.
6. Install lower bolt on starter. Torque to 40 lb. ft.
7. Connect shift linkage to transmission.
8. Connect modulator line.
9. Connect speedometer cable.
10. Install transmission support.
11. Install drive shaft. Torque U-Bolts to 18 lb. ft.
12. Install flywheel cover pan. Torque to 15 lb. ft.
13. Install engine support brackets.
14. Reconnect exhaust system.15. Attach stabilizer supports and tighten stabilizer
bolts in lower control arms.
16. Lower car.
17. Install starter bolts. Torque to 40 lb. ft.
18. Reconnect battery.
19. Fill transmission with fluid as described in
Specifications. Check selector lever and detent cable
adjustment.
Removal GT1. Disconnect battery.
2. Remove dipstick.
3. Pull throttle control rod off ball pin.
4. Remove screws from fan shroud.
5. Raise car and provide support for front and rear.
6. Remove heat protection shield from right side to
make room for exhaust pipe removal.
Figure 7C-957. Detach exhaust pipe from manifold flange.
8. Unhook damper rings on front muffler and tail
pipe from brackets on body floor panel. Place ex-
haust pipe assembly onto rear axle. See Figure 7C-
96.9. Remove propeller shaft. Make sure that spring in
front universal joint does not get lost.
AUTOMATIC TRANSMISSION JC- 97
Figure 7C-101Figure 7C-103
Figure 7C-102
19. Pry detent cable and oil cooler pipes out of retain-
ers on transmission oil pan.
20. Unscrew speedometer cable and pull it out of
speedometer driven gear housing.
21. On both engine sides unscrew engine support
brackets from torque converter housing. Slacken’
front attaching bolt only. See Figure
7C-105.22. Remove torque converter housing cover plate.Figure 7C-104
23. Mark flex plate and converter for reassembly in
same position.
24. Unscrew the three torque converter to
flex plate
attaching bolts. See Figure
7C-106.25. Pry transmission loose from engine.
26. Move transmission rearward to provide clear-
ance between converter and flex plate to install con-
verter holding tool J-21366. Lower transmission and
move to bench.
7C- 981973 OPEL SERVICE MANUAL
Figure 7C-105Figure
7C-106Installation GT
1. Assemble transmission to suitable jack and raise
into position. Rotate converter to permit coupling
with flywheel in original relationship. Remove hold-
ing fixture.
2. Install tiller tube and converter housing to engine
bolts. Torque to 35
lb.ft.3. Install flywheel to converter bolts. Torque to 30
lb.ft.4. Install detent cable.
5. Connect oil cooler lines.6. Install lower bolt on starter. Torque to 40 lb.ft.
7. Connect modulator line.
8. Connect speedometer cable.
9. Connect shift linkage.
10. Install transmission support.
11. Install drive shaft. Torque U-bolts to 18 lb.ft.
12. Install flywheel cover pan.
13. Reconnect exhaust system and heat shield.
14. Install engine support brackets.
15. Lower car,
16. Install starter bolts, Torque to 40
lb.ft.17.
C:onnect battery.
18. Fill transmission with fluid, as described in
Specifications. Check selector lever and detent cable
adjustment.
DISASSEMBLY, INSPECTION AND REASSEMBLY
Transmission Installation Into Holding FixtureI. Remove transmission tiller tube.
2. With transmission on cradle of portable jack,
remove converter assembly by pulling straight out.
Converter contains a large amount of oil.
3. Install holding fixture, J-8763-01, on transmission.
4. Install holding fixture and transmission into hold-
ing base tool J-3289-20 with bottom pan up. See
Figure
7C-107. Do not overtighten.
Figure
7C-107