1973 OPEL 1900 rod

7C- 561973 OPEL SERVICE MANUALMODULATORFigure
7C-42 Low Speed Downshift Timing Valve
During a “coast” condition, the vacuum is high and
the modulator pressure is zero. The spring holds the
timing valve in a bottomed position and the servo
release pressure is exhausted through a restricting
orifice, thus delaying the apply of the servo.
During a “power on” 3-2 downshift at lower car
speeds, the servo must be applied rapidly. During
such a shift, the vacuum will be somewhat lower and
the resulting modulator pressure will force the valve
over against the spring. This provides an unrestricted
passage for servo release, thus permitting rapid apply
of the servo.
High Speed Downshift Timing Valve
When a 3-2 downshift is “forced” at high car speeds,
the application of the band must be delayed. Servo
apply pressure is directed through the high speed
downshift timing valve. See Figure
7C-43.The timing valve is held in a bottomed position by
the spring at lower car speeds. This permits an unre-
stricted
flow for servo apply. At higher car speeds,
approximately 25 to 35 MPH, (depending on axle
ratio and engine), governor pressure forces the valve
over against the spring. This closes off the direct feed
to servo apply and the feed is controlled by a fixed
orifice.While it may outwardly appear that the functions of
the two downshift timing valves are contradictory,
whether or not the application of the band is delayed
during a 3-2 downshift is a combined function of car
speed and throttle position.
--Figure
7C-43 High Speed Downshift Timing Valve
Second Clutch Orifice Valve
For reasons of shift timing, it is necessary to have
different restricting orifice sizes for the feed and ex-
haust of the second clutch. This is accomplished by
introducing a “one way” ball check in the second
clutch circuit. See Figure
7C-44.2ND CLUTCH
I?C-44
Figure
7C-44 Second Clutch Orifice Valve
When the second clutch is being applied, the apply
pressure seats the ball and the feed is directed
through a single orifice. During the release of the
clutch, the ball is unseated and the clutch can ex-
haust at a faster rate through the two orifices.

AUTOMATIC TRANSMISSION7c-57
ACCUMULATORFigure
7C-46 1-2 Accumulator
l-2 AccumulatorIn order to obtain a smooth 1-2 upshift, it is neces-
sary to control the rate of pressure build-up in the
second clutch. This is accomplished by introducing
a hydraulic modulator in the clutch circuit. Prior to
the second clutch being applied, the spring holds the
accumulator piston in an upward position. When
line pressure is introduced to the second clutch cir-
cuit by way of the 1-2 shift valve, the pressure in the
second clutch will be permitted to build up rapidly
until the clutch pressure acting on the accumulator
piston is sufficient to overcome the accumulator
spring. As the clutch pressure increases on the top
side of the accumulator piston, the piston will start
to move against the spring force until the piston is
forced all the way down. This provides a time delay
for the apply of the second clutch before the pressure
reaches its maximum value. When upshifts are made
at heavier throttle, it is necessary to increase the
pressure at which this time delay occurs. This is
accomplished by introducing a vacuum sensitive
pressure from the 1-2 accumulator valve to the bot-
tom side of the accumulator piston. This pressure
assists the spring and the clutch pressure will have to
build up to a higher value before the accumulator
piston will move. See Figure
7C-46.
SERVO7c-47
Figure 7C-47 Low Servo
Low ServoThe low servo provides a dual function. See Figure
7C-47. It is the means by which the band is applied
and it provides an accumulator action for the third
clutch during a 2-3 upshift.
In first and second gear, servo apply pressure acting
on the bottom side of the low servo piston moves the
piston against the spring force and applies the band.
During a 2-3 upshift, third clutch pressure is intro-
duced to the top side of the servo piston. When third
clutch pressure, acting on the top side of the piston
and assisted by the servo release spring, is sufficient
to overcome the servo apply force, the servo will
move downward. This removes the apply force from
the band and the band will release while the clutch
is being applied. During the downward movement of
the piston, a time interval occurs which cushions the
apply of the third clutch in the same manner that the
1-2 accumulator cushions the apply of the second
clutch. It is because of this accumulator action that
the band adjustment is so critical. The main function
of the band adjustment is to control the servo release
spring load rather than to control band clearance.

c. Operation of Controls in Drive Range Second Gear
Reverse Clutch
ReleasedThird Clutch Released
Second Clutch AppliedLow Band Applied
Sprag Over Running
As the vehicle increws speed. the govwnor
allow more drive oil 10 pass through, and this increased pressure, acting on the end of the 1 2 shift
vahre. overcomes the I 2 shift valve spring pressure and allovn drive oil 10 pasr through the valve to feed the second clutch oil parsages.Second clutch oil passes through the second clutch orifice control valve, seating the ball and is metered to the second clutch piRon
to begin to apply
the second clutch, whileportion of the oil is directed
10 the accumulator. As the upper portion of the accumulator fills with second clutch oil. itovercomes the leer prewre of 1 2 accumulator oil and spring at the bottom of the accumulator piston. forcing the piston downward. The upper
portion of the accumulator is now filled, allowing full oil preaure
to the second clutch piEton far the final apply. The accumulator, therefore, acts as a
reservoir
10 produce a damping effect for a smooth second clutch apply and the 1 2 shift.
Second clutch oil from the 1 2 shift
valve is simultaneously directed to the 2 3 shift valve to be used as the oil source for the 2 3 shift.
Summary
The second clutch is on. the band is on, the transmission is in drive range
i second gear.

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.

AlITOMATIC TRANSMISSION 7C- 85
ConditionCtSlSl?8. After full throttle upshifting
transmission shifts immediately
into lower gear upon easing off
accelerator pedal.a) Detent valve stuck in open position,
b) Detent cable stuck.
c) Modulator vacuum line interrupted.
9. At higher speeds, transmission
shifts into lower gear.a) Retaining pin of selector lever shaft
in transmission dropped out.
b) Loose connection of selector lever
linkage to manual valve.
c) Pressure loss at governor.
10. Hard disengagement of selector
lever from “P” position.a) Steel guide bushing of parking
paw1actuating rod missing.
b) Manual selector lever stuck.
Shifts1. Slipping l-2 upshifts (engine
flares).a) Low oil pressure.
b) Sealing ball in valve body dropped out.
c) Second clutch piston seals leaking.
d) Second clutch piston centrifugal ball
stuck open.
e) Second clutch piston cracked or broken.
f) Second clutch plates worn.
g) Seal rings of oil pump hub leaky.
2. Slipping 2-3 upshifts (engine
flares).a) Low oil pressure.
b) Band adjustment loose.
c) Third clutch piston seals leaking.
d) Third clutch piston centrifugal ball
stuck open.
e) Third clutch piston cracked or broken.
f) Wear of input shaft bushing.
g) Sealing ball in valve body dropped out
3. Abrupt l-2 upshift.a) High oil pressure.
b) l-2 accumulator valve stuck.
c) Spring cushion of second clutch broken,
d) Second gear ball valve missing.
4. Abrupt 2-3 upshift.
a) High oil pressure
b) Incorrect band adjustment.
5. Abrupt 3-2 detent downshift at
high speed.a) High speed downshift valve stuck open.
b) Band adjustment.

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”,

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.