transmission oil OPEL GT-R 1973 Service Manual

LUBRICATION AND MAINTENANCE OC-7SERVICESLUBE AND GENERAL MAINTENANCE
Vehicle operation under conditions such as heavy
dust, continuous short trips, use of other than un-
leaded or low lead fuels or pulling trailers, is not
considered normal use and therefore more frequent
maintenance will be required. Such additional
maintenance requirements are included where appli-
cable.
Engine OilChange each 4 months or
3,COO miles, whichever
occurs first, or each 2 months or
3,ooO miles when
the vehicle is operated under the following condi-
tions: (a) driving in dusty conditions, (b) trailer pull-
ing, (c) extensive idling or (d) short-trip operation at
freezing temperatures (with engine not thoroughly
warmed-up).Engine oils have a definite effect on ease of starting,
oil economy, combustion chamber deposits and en-
gine wear. It is recommended that a” oil which,
according to the label on the can is; (1) intended for
service SE and (2) passes car makers’ tests be used.
Oils confotming to these types contain detergent ad-
ditives. -
Select the proper oil viscosity from Figure OC-3.
Engine Oil FilterReplace at the first oil change and every other oil
change thereafter using Part No. 7965051 or equiva-
lent.
ChassisLubricate transmission shift linkage, hood latch and
parking brake cable guides and linkage.
Fluid LevelsCheck level of fluid in brake master cylinder, battery,
engine, axle, transmission and windshield washer.
Engine coolant also should be checked for proper
level and for corrosion and freeze protection to at
least -20°F or to the lowest temperature expected
during the period of vehicle operation. Proper engine
coolant also provides corrosion protection.
Any significant fluid loss in any of these systems or
units could mea” that a malfunction is developing
and corrective action should be taken immediately.
A low fluid level in the brake master cylinder front
reservoir could also be a” indtcator that the disc
brake pads need replacing.
The engine oil should be maintained at proper level.
The best time to check it is before operating the
engine or as the last step in a fuel stop. THIS WILL
ALLOW THE NORMAL OIL ACCUMULA-
TION IN THE ENGINE TO DRAIN BACK IN
the crankcase. To check the level, remove the oil
gauge rod (dipstick), wipe it clean, and reinsert it for
a” accurate reading. The oil level should be main-
tained in the safety margin, neither going above the
“FULL” mark “or below the “ADD OIL” mark.
See Figure OC-4.
DIP STICK MUST BE
INSERTED TO STOP
---L- -FULL+, 1 OT. ,-ADD
OIL
Figure OC-4 Engine Oil Dipstick
All models are equipped with tandem brake cylin-
ders. Maintain fluid level between MIN and MAX
marks on reservoir. See Figure OC-5. When adding
fluid use Delco Supreme No. 11 or equivalent.
TiresTo equalize wear, rotate tires as illustrated in Figure
OC-6.Adjust clutch when necessary as indicated by the
clutch warning lamp on Opel 1900 and Manta or

IoC-91973 OPEL SERVICE MANUAL
Figure OC-5 Brake Master Cylinder
I
Figure OC-6 Tire Rotation Methods
when the clutch pedal has in excess of 1
l/4 inch fr&
travel. See Figure OC-7.
Rear Axle
Change lubricant every
12,ooO miies when vehicle is
used for pulling a trailer.
Cooling SystemCheck at 12-month or
12,000~mile intervals, wash
radiator cap and filler neck with clean water, pres-
sure test system and radiator cap for proper pressure
holding capacity (tighten hose clamps and inspect
condition of all cooling and heater hoses). Replace
hoses every 24 months or 24,000 ,miles or earlier :if
checked, swollen or otherwise deteriorated.
Also each 12 months or
12,ooO miles, clean exteribr
of radiator core. Every 24 months or
24,OCO miles,Floor-Pan
-Clutch Pedal
Figure OC-7 GT Clutch Lash
drain, flush, and refill the cooline svstem with a new
coolant so&ion of permanent
6~; anti-freeze and
water for protection-of -20°F.
D-6 NOT REMOVE
RADIATOR CAP WHEN SOLUTION IS HOT
AND UNDER PRESSURE.
Wheel BearingsClean and repack front wheel bearings with a lubri-
cant as specified on the lubrication chart, Figure
oc-1.
Automatic Transmission FluidUnder normal driving conditions, change the trans-
mission fluid every 24,000 miles. Under unusual con-
ditions such as constant driving in heavy city traffic
during hot weather, trailer pulling, etc., this service
should be performed at
12,COO mile intervals.
General Motors DEXRON Automatic Transmis-
sion Fluid, which has been especially formulated and
tested for use in your automatic transmission, is
recommended. Other automatic transmission fluids
identified with the mark DEXRON are also recom-
mended.
Check the fluid level at each engine oil change
period. To make an accurate fluid level check:
1. Drive car several miles, making frequent starts and
stops, to bring transmission up to normal operating
temperature (approximately
180-190’F.)2. Park car on a level surface.
3. Place selector lever in “Park” and leave engine
running.

CC-10 1973 OPEL SERVICE MANUAL
wiper blades. Check amount and direction of fluid
sprayed by washers during use.,
E. Defrosters - Check performance by moving con-
trols to “DEF” and noting
am$nmt of air directed
against the windshield.
I
F. Wheel Alignment and
Balabce - In addition to
abnormal tire wear, the need fbr wheel alignment
service may be indicated by a pull to the right or
!eftwhen driving on a straight and level road. The need
for wheel balancing is usually
iddicated by a vibra-
tion of the steering wheel or
se;+ tihile driving at
normal highway speeds.I
IG. Brakes
- Be alert to illumiriation of the brake
warning light or changes in braking action,
SUCK as
repeated pulling to one side, unusual sounds when
braking or increased brake pedal travel. Any of thesecould indicate the need for
brakk system inspection
and/or service.
H. Parking Brake and Transmission “PARK”
Mechanism
- Check parking brake holding ability by
parking on a fairly steep hill and restraining the vehi-
cle with the parking brake only.
eon cars with auto-
matic transmissions, check the holding ability of the
“PARK” mechanism by releasing all brakes after
the transmission selector lever hak been placed in the“P” position.
I. Glass
- Check for broken, scrritched, dirty or da-
maged glass on vehicle that
coulld obscure vision’or
become an injury hazard.
J. Lights and Buzzers
- Check all instrument panel
illuminating and warning lights,’ seat belt reminder
light and buzzer, ignition key
b&er, interior lights,
license plate lights, side marker! lights, headlamps,
parking lamps, tail lamps, brake lights, turn signals,
backup lamps, and hazard warding flashers. Have
someone observe operation of
&ach exterior light
while you activate the controls: The operation of
instrument panel warning lights is covered in the
“Starting and Operating“ section of your
Own&%
Manual.K. Transmission Shift Indicator
‘- Check to be sure
automatic transmission shift
indiCator accurately i”-
dicates the shift position selected.
I
CAUTION: Before making thk check below,I
be sure to have a clear dist&e ahead and:
behind the car, set the parking brake and
firmly apply the foot brake.
Do not depress
accelerator pedal. Be prepared to
turn off ’
ignition switch
immediat+y if engine
should start.L. Starter Safety Switch (Automatic Transmissibn
Cars)
- Check starter safety switch by placing the
transmission in each of the driving gears while
at-tempting to start the engine. The starter should oper-ate only in the Park (“P”) or Neutral (“N”)
positions.
M. Horn
- Blow the horn occasionally to be sure thatit works. (Ignition switch must be in the “ON” posi-
tion.)
N. Seat Back Latches
- Check to see that seat back
latches are holding by pulling forward on the top of
each folding seat back.
0. Rearview Mirrors and Sun Visors
- Check that
friction joints are properly adjusted so mirrors and
sun visors stay in the selected position.
P. Door Latches
- Check for positive closing, latch-
ing and locking.
Q. Hood Latches - Check to make sure hood closesfirmly by pressing on the hood at the latching point
after each closing. Check also for broken, damaged
or missing parts which might prevent secure latch-
ing.R. Fluid Leaks
- Check for fuel, water, oil or other
fluid leaks by observing the ground beneath the vehi-cle after it has been parked for a while. If gasoline
fumes or fluid are noticed at any time, the cause
should be determined and corrected without delay
because of the possibility of fire.
S. Exhaust System
- Be alert to any change in the
sound of the exhaust system or a smell of fumes
which may indicate a leak.
Head Restraints
- Check that no head restraint
components are missing, damaged or loose. (Does
not apply to GT Models).
Disc BrakesCheck brake pads and condition of rotors while
wheels are removed during tire rotation. (Note belowregarding more frequent checks also applies to disc
brakes.)
Parking and Drum BrakesCheck drum
brake linings and other internal brake
components at each wheel (drums, wheel cylinders,
etc.). Parking brake adjustment also should be
checked whenever drum brake linings are checked.
NOTE: More frequent checks should be
made if driving conditions a.nd habits result
in frequent brake application. When brakes
require relining, it is recommended thatyou use those genuine General Motors
parts specified for your car,and Delco fluid
as required.

19- 12 1973 OPEL SERVICE MANUAL :ConditionPosiible CauseCorrection4. Voltage drop.1. Check wiring and wiring
connections.
5. Overrun&g clutch slips.1. Replace overrunning clutch.
The cranking motor keeps
on rotating after ignition
switch is off.1. Ignition
{witch does not
cut off or solenoid switch
sticks.
1, Immediately disconnect cranking
motor cable from battery. Inspect
and/or replace or repair ignition and
solenoid switches as required.
The drive pinion does notdemesh after engine has
been cranked.1. Drive pinion or ring gear
1. Clean components as specified.
teeth clogged or flattened.Replace as required.
Return spring slack or broken.MAlNTEilANCE AND ADJUSTMENT
/
STARTING SYSTEM CHECKS
Voltage Loss ChecksWhen the starter cranks too slowly, check the bat-
tery state of charge and all electrical connections
between the battery and starter.
1. Turn on headlights and
opera’te starter. If head-
lights dim considerably when starter is engaged, the
battery may be discharged or be defective. Check the
battery.
2. If the headlights stay bright but the starter d&s
not turn over, the starter cables may be faulty or the
starter defective.
(a) Test battery voltage while cranking engine
1(9volts minimum).
(b) Check voltage from starter tkrminal of solenoid
to starter frame while cranking engine.
3. The difference in readings taken in Operations 2a
and 2b above represents the
volt& drop through the
cables and solenoid switch. Voltdge drop should
Gotexceed
.5 volt.
4. Locate excessive resistance as follows:
(a) Turn voltmeter to scale above 12 volts and con-
nect voltmeter leads
across connection or switch: to
be checked.
(b) With starter switch closed, turn voltmeter switch
to lowest scale and take reading as quickly as possi-
ble, then turn switch back to higher scale and stop
cranking engine.(c) Voltmeter must not read more than
.2 volt across
any
c:onnection. If voltmeter reads more than .2 volt,
the
d~efect must be corrected.
Starter Current Draw - Lock Test1. Make sure battery is fully charged and in good
condition.
2. Connect a volt ampere starter tester according to
manufacturer’s instructions.
3. Pull parking brake on securely, shift transmission
into 4th (direct) gear and actuate starter. (Starter will
not
t,urn engine because engine is locked through
transmission.)
4. While starter is actuated, read voltage and current.
Refer to Specification Chart.
(a) Voltage low
_ poor battery or a voltage loss in the
starter circuit.
(b) Current high
- short circuit in starter. Overhaul
starter.
(c) Current low
- commutator dirty, brushes worn,
solenoid switch contacts defective or open circuit in
starter. Overhaul starter.
Starter Current Draw. On Car1. Bring engine to normal operating temperature.
2. Stop engine and disconnect coil wire from dis-
tributor.
3. Ground coil wire to prevent excessive coil voltage
build up.

STARTING SYSTEMlB- 13
4. Connect test equipment and, with transmission in
neutral, turn engine over until voltage stabilizes.
Note read.ings.5. Current draw should be between 90-130 amperes.
I3. Remove end frame from field frame and pull both
insulating tubes out of field frame.
4. To prevent brushes from coming out when remov-
ing the field frame, place a 29 millimeter socket over
commutator while lifting up on the field frame. The
brushes will be held in place by the socket. See FigurelB-4.
STARTER
:OVERHAULStarter
R&~moval1.
Dixon&t starter wiring.
2. Remove starter support bracket.
3. Removk two starter bolts, one nut and lockwash-en.
4. Removi starter.
Starter
Di+assembly1. Hold starter in a vise, as shown in Figure
lB- 3.
Mark end’ frame and field frame to ensure correctinstallatioli of parts on reassembly.
rTHRU BOLTS7Figure
18-4 Removing Field Frame
5. Remove the two (2) solenoid attaching screws and
remove solenoid and spring.
Figure 1 B-3 Cranking Motor in Vise
2. Remove both starter through bolts and field coil
end from solenoid switch lower threaded bolt. See
Figure lB13.Figure
lb5 Driving Retaining Ring Back

WINDSHIELD WIPERSlE-41
Figurk 1 E-l 3 Cut Off Positive Brush Leads
i
Figure iE-14 Remove Negative Brush Retaining
S.X?WI
Cleaning apd Inspection of PartsWith the ekception of electrical parts and bushings,
clean all components in a cleaning solvent.
1. Check irmatare windings for ground, or open
circuit. If
b ground or open circuit is evident, the
armature must be replaced. If the armature checks
out, the c 2. Check brush springs. Spring pressure of new
brushes should be 6.35 to 8.47 ounces. Spring pres-
sure of worn brushes should be at least 3.5 ounces.
In case of /ower spring pressure, replace springs.
3. Check blushes for wear and replace if necessary.
Minimum brush length should be
.24’inch.4. Check d$ven gear for wear and replace if neces-
sary.
Assembly l/8inch layer’ of grease meeting GM Specification
02383. I
2. Install
d&en gear into housing3. Apply a small amount of grease to ball cavity of
driven gear and insert ball. See Figure lE-15.
Figure lE-15 Insert Ball into Driven Gear
4. Install transmission housing cover. See Figure
lE-
16.2. DRIVEN GEAR
3. CONTACT SPRINGS
4. TRANSMISSION
HOUSING COVER
Figure 1 E-l 6 Install Transmission Housing
Cover5. Solder positive brush lead(s) to brush holder(s).
Hold brush lead with needle nose pliers to prevent
solder from running up wire strands. See Figure
lE-
17.6. Install negative brush
7. Apply a small amount of grease to end of armature
shaft. Lightly oil armature shaft.
8. Insert brush springs and brushes into brush hold-
ers. Slide armature into housing, taking care not to
damage brushes.

1 J- 72 1973 OPEL SERVICE MANUAL
I
WIRING IDIAGRAMS
CONTENTS
Subject
1973 WIRING DIAGRAMS: Windshield Wiper and
Horn:- Opel 1900 -
Manta....................................I.............. ..............................
Windshield Wiper and Horn’- Rallye ..........................
Windshield Wiper
andHorn!-GT
..................................
Turn Signal and Hazard Flasher
-
Opel 1900 - Manta !
........................................................
Turn Signal and Hazard Flasher
- GT ..........................
Oil, Fuel,
Temp.: Tach, Stop and Brake
Warning Light
.GT........................................................
Blower Motor, Lighter and
Rackup Lights -
Qpel 1900.Manta ........................................................
Blower Motor and Lighter
.,GT....................................
Indicator Lights and Gauges
- Opel 1900 -
Manta ........................................................................\
........
Indicator Lights
andGauges.Rallye ..........................
Dome Light and Buzzer
- Opel 1900 - Manta..........
Dome Light, Buzzer and Clock - GT ............................
Headlamps
- Opel 1900 ’
....................................................
Headlamps
.Mantaj............................................................
Headlamps and Fog Lights
.Rallye ..............................
Headlamps, Parking, Tail and Instrument
PanelLighting.GT ........................................................
Left Parking and Tail Lights
- Opel 1900 -
Manta ..................................i.............................................
Right Parking and Tail Lights
- Opel 1900 -
Manta................. ..*............................................................
Starting, Ignition and Charging
-
Opel 1900.Manta..........i.............................................
Starting, Ignition and Charging
- GT ..........................
Instrument
Panel.GT ......................................................
A/C Generatorand Regulator
- All Models..............
Seat Belt Warning System (Manual Transmission)
-Opel1909-Manta ..........................
Seat Belt Warning System (Automatic Transmission)
.Opel 1900 - Manta..........................
Seat Belt Warning System (Manual Transmission)
- GT........................................................ Page No.
1 J-74
1 J-75
1 J-76
1 J-77
1 J-78
1 J-79
1 J-80
lJ-81
1 J-82
1 J-83
1 J-84
1 J-85
1 J-86
1 J-87
1 J-88
1 J-89
1 J-90
1 J-91
1 J-92
1 J-93
1 J-94
1 J-95
1 J-96
1 J-97
1 J-98

4A- 21973 OPEL SERVICE MANUAL
PROPELLER SHAFT AND CENTRAL JOINT
CONTENTS
Subject
DESCRIPTION AND OPERATION:
PropellerShaftandCentralJoint. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DIAGNOSIS: (Not Applicable)
MAINTENANCE AND ADJUSTMENTS: (Not
Applicable)
MAJOR REPAIR:
’Propeller Shaft Removal andInstallation
. . . . . . . ..-....Disassembly andAssembly of CentralJoint
. . . . . . . . . . . .SPECIFICATIONS:
Propeller Shaft and Central Joint Specifications . .
DESCRIPTION AND OPEqATlON
PROPELLER SHAFT AND CENTRAL JOINTDue to the use of both automatic and manual trans-
missions, propeller shafts of various lengths are re-
quired depending upon vehicle, engine, and
transmission (manual or automatic) application. The
propeller shaft is of a strong design due to increased
engine torque. It is also a one piece tubular shaft, but
it has two universal joints. See Figure 4A-1. The
front universal joint attaches to the transmission out-
put shaft by a splined slip joint. The rear universal
joint attaches to the pinion extension shaft flange by
Page No.
4A-2
4A-3
4A-3
4A-6two U-bolts. The splines of both propeller shafts are
lubricated internally with transmission lubricant. An
oil seal in the rear of the transmission extension pre-
vents loss of lubricant and entrance of harmful for-
eign material.
The torque tube which houses the drive pinion exten-
sion shaft is bolted to the differential housing. The
torque tube is pivoted in rubber elements of the cen-
tral joint support bracket which is bolted to the floor
panel. The support bracket and rubber parts of the
torque tube
arc termed the central joint. The front
end of the drive pinion extension shaft rides in a ball
bearing mounted in rubber in the central joint.
CENTRAL JOINT\REAR U-JOINT
FRONT U-JOINT
4A-1Figure 4R1 Propeller Shaft

PROPELLER SHAFT AND CENTRAL JOINT4A- 3MAJOR REPAIR
PROPELLER SHAFT REMOVAL AND
INSTALLATION
Removal
1. Raise rear of car and support on jack stands at rear
jack brackets.
2. Disconnect parking brake cable equalizer from
rod.3. On the Opel
1900 and Manta, unhook parking
brake cable from floor panel.
4. On the Opel 1900 and Manta, unhook exhaust
system and let it down.
5. Mark the mating parts of the U-joint and the drive
pinion extension shaft flange.
6. Loosen bolt locks and remove bolts or nuts.
7. Work propeller shaft slightly forward, lower rear
end of shaft and slide assembly rearward. Remove
thrust spring from front of propeller shaft.
S. Install plug in transmission extension housing to
prevent loss of lubricant.
installation
CAUTION:
Fasteners in the foJlowing steps are impor-
tant attaching parts in that they could affect the
performance of
vital components and systems, and-
/or could
result in major repair expense. They must
be replaced with one of the
samepart number or with
an equivalent part
ifreplacement becomes oecessary.
Do not use a replacement part of lesser quality or
substitute design. Torque values must be used as
specirid during reassembly to assure proper reten-
tion of these parts.1. Remove plug from rear of transmission.
2. Slide thrust spring onto transmission output shaft
and slide propeller shaft through the oil seal and onto
the transmission output shaft. Make certain trans-
mission rear seal is not damaged.
3. Align rear universal joint and pinion flange locat-
ing marks and secure with respective bolts and lock
plates. Torque bolts to 11
lb.ft. Bend lock plate tangs
to secure bolts or nuts.
4. Connect parking brake cable equalizer to brake
rod and adjust to specifications.
5. On the Opel 1900 and Manta connect parking
brake cable to floor panel.DISASSEMBLY AND ASSEMBLY OF THE
CENTRAL JOINT
Disassembly of Central Joint1. Raise and support rear of car under axle tubes.
2. Release brake line bracket from rear of torque
tube.3. Disconnect parking brake cable equalizer and re-
turn spring from brake rod.
4. On the Opel 1900 and Manta, unhook exhaust
system and let it down.
5. Mark universal joint and flange. Disconnect pro-
peller shaft from flange and support it out of the way.
6. Support torque tube with floor jack using mini-
mum pressure.
7. Remove the central joint bracket to underbody
attaching bolts.
8. Allow floor jack to lower the torque tube.
9. Disconnect torque tube from differential carrier by
removing the attaching bolts.
10. Install pinion flange holder J-8614 and remove
self-locking flange nut. See Figure 4A-2.
FLANGE HOLDER4A-2
Figure 4A-2 Removing Pinion Flange Nut
11. Pull pinion flange using J-8614 adapter. See Fig-
ure 4A-3.
12. Remove drive pinion extension shaft from torque
tube using a soft faced mallet. See Figure 4A- 4.
13. Removal ball bearing from cushion.
14. With torque tube placed in vise remove support

REAR AXLE48. 9
MAJOR REPAIRREMOVAL AND INSTALLATION OF REAR AXLE
ASSEMBLYRemoval
1. Raise rear of car with floor jack under differential
carrier and position jack stand under jack bracket on
each side of car. Remove rear wheel assemblies and
one brake drum.
2. Disconnect parking brake cable equalizer and re-
turn spring from brake rod.
3. Detach parking brake cable from actuator lever
and backing plate at wheel with brake drum
removed. Disconnect cable from lower control arm
brackets and pull loose end over exhaust system.
4. Disconnect shock absorbers at lower end.
5. Disconnect track rod at left end.
6. On cars equipped with a stabilizer rod, disconnect
the shackles at rear axle housing.7. Disconnect universal joint from pinion flange and
support or tie propeller shaft out of way after mark-
ing mating areas. If propeller shaft is removed, install
plug in rear of transmission to prevent loss of lubri-cant.8. Disconnect brake hose from brake pipe at differen-
tial and remove retaining clip.
9. Lower rear axle assembly far enough to remove
coil springs.
10. Remove central joint support bracket to under-
body retaining bolts.
11. Disconnect lower control arms at rear axle assem-
bly bracket and roll the assembly from under the car.
See Figure
4B-2.Installation
CAUTION: Fasteners in the following steps are impor-tant attaching parts in that they could affect the
performance of vital components and systems, and-
/or coo/d
resuJt in major repair expense. They must
be rep/aced with one of the same part number or withREAR SHOCK ABSORBERS
SPRING SEAT
4B-1Figure
4B-l Differential and Rear Suspension Assembly