oil change 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.

I
ilC- 201973 OPEL SERVICE MANUAL
There is also a plastic hood slipped over the distrivu-tar cap with an outlet for the ignition cables as an
added protection against moisture from the outside.
See Figure lC-2.
Figure lC-2 Ignition Distributor With Hood Installed
MAINTENANCE AND ADJUSTMENTS
CONTACT POINT REPLACEMENT
Removing Contact Points1. Remove contact support lock
,screw and remqve
contact point support. If condenser is to be replaced,
it will be necessary to replace condenser and
1eads;asan assembly.
Installing Contact Points1. Lightly lubricate distributor cam with high tein-perature cam and ball bearing lubricant. Excessive
lubricant will throw off into contact points.
:
,
2. Position support on breaker plate and install lock
screw leaving slightly loose for later adjustment..
3. Plug breaker arm wire in.
4. Adjust breaker point gap to ,016”.
/
DWELL ANGLE ADJUSTMENT
1. Connect dwell meter.
2. Remove distributor cap. Remove rotor. Loosen
breaker point set screw approximately
l/8 turn.
3. Insert screwdriver in notch of stationary breaker
point. Observe dwell meter while cranking engine.
Twist screwdriver as required to obtain a reading of
50 degrees plus or minus 3 degrees.4. Tighten breaker point set screw, then recheck
dwell.
5. Install rotor and cap.~Start engine and recheck
dwell. It is important that dwell be rechecked, as
instal~lation of rotor and cap will sometimes change
the dwell angle.
IGNITION TIMING ADJUSTMENT
Preliminary Timing (Engine Won’t Run)To time the ignition on any engine which will run,
use subparagraph b only. However, if the timing of
an engine is completely off, the following procedure
must first be used to get the engine to run.
1. With rocker arm cover removed, rotate crankshaft
in a clockwise direction until both valves for No. 1
cylinder are closed and the timing marks line-up.
(Valves are completely closed if rocker arms can be
“rocked” slightly.)
2. Install distributor in engine so that vacuum ad-
vance unit is in original position and notch in dis-
tributor rotor lines-up with notch in housing. See
Figure lC-3. If distributor does not seat in engine
block., turn distributor shaft so that rotor points
about 20 degrees clockwise from distributor timing
notch
(see Figure lC-18), then press lightly on dis-
tributor housing while cranking engine with starter.
After oil pump tang snaps into slot in distributor
shaft, start timing again from Step 1, leaving dis-
tributor installed.
Figure lC-3 Rotor Position for Filing No. 1 Cyliqder
3. Install distributor clamp and bolt, leaving bolt just
loose enough to permit movement of distributor. In-
stall distributor primary wire.L

lD- 28 1973 OPEL SERVldE MANUAL
.CHARG;ING SYSTEM
I
CQNTENTS
Subjyct’
DESCRIPTION
4ND OPERATION‘:
Alternator
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . . . . . . .
Regulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . \
. . . . . .
DIAGNOSIS: (Not Available):
MAINTENANCE AND ADJUSTMENTS:
Alternator Tests
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Regulator Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAJOR REPAIR:
Alternator
Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . .
Alternator Disassembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . .
Alternator Reassembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . .
AlternatorInstallation. . . . . 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . . . . . . .
SPECIFICATIONS:
Alternator
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . .
Regulator. . . . . 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
Page No.
1 D-28
1 D-29
1 D-29
1 D-29
1 D-30
lD-31
1 D-34
1 D-35
1 D-35
1 D-35
DESCRIPTION AND OPERATION
ALTERNATOR DESCRIPTION
The Kl, 35 amp alternator is standard equipment on
all 1973 models.
Figure lD-1 Alternator Installed
The alternating current generator (alternator) is a
continuous-output (even at idle), diode rectified gen-
erator. See Figure
lD-1.
The rotor, which carries the field winding, is mounted in ball bearings at both ends. Each bearing
has a sealed-in grease supply which eliminates the
need for periodic lubrication. Two brushes and two
slip rings are used. One brush conducts the current
provided by the voltage regulator to one end of the
field coil; the other brush conducts the current from the other end of the rotating field coil to ground.
The three phase
stator windings are assembled on the
inside of a laminated core that forms the center sec-
tion of the alternator frame. Nine rectifier diodes are
connected to the
stator windings (three to each phase
lead). The diodes change the alternator AC voltages
to DC voltage coming out of the B positive and the
D positive terminals of the alternator.
If the alternator will not meet output specifications
when supplied with full field current, the
assembly
must be overhauled. If the voltage regulator does not
limit maximum voltage within specifications, adjust
the voltage regulator. If steady voltage regulation,
within specifications, cannot be achieved, the voltage
regulator assembly must be replaced.

1F. 46 1973 OPEL SERVICE MANUAL
’
/
Headlight High-Low Beam Control and Passing:
SignalI
When the headlights have been switched on, high
and low beam selection is made by raising the direc-
tional signal lever toward steering wheel. Each
ti&the lever is raised, beam position, will change.
When the headlights are not on, a flashing headlight
signal may be given by raising and lotiering the di-
rectional signal lever. With the headlights on and
inlow beam position, raising and lowering the direc-
tional signal lever will also cause the headlights to
flash.
Fog Light SwitchAll Rallye models are equipped with two white f?g
lights mounted below the front bumper.
The fog light toggle switch is located on the
insty-ment cluster to the left of the temperature and
fuelgauge cluster.
/
The fog lights can be turned off at any time by the
toggle switch, but can only be tyrned on when: :
1. The ignition switch on or the
?gine running.!
2. The fog light toggle switch lower half is pushed
in.3. The parking lights and/or low beam headlights
are
OKThe fog lights are automatically turned off if the
ignition switch is on and the headlights are switched
to high beam position.
Courtesy LightThe courtesy light illuminates the interior of the Car
when any door is opened. The courtesy light can also
be turned on with all doors closed by tilting the l&s.
GT Headlamp MechanismThe concealed headlamps are moved mechanically.
Pushing actuating lever on left side of console opens
headlamps and pulling lever closes headlamps. Two
(2) meshing gear segments convert the movement, of
the lever to a rotation of 180 degrees. The pivots of
the headlamps lie below the centerline so that with
headlamps in closed position, the headlamp housing
is flush with front sheet metal. Refer to Group 110,
Section “F”, for service procedures on the GT head-
lamp mechanism.
A white indicator lamp in the instrument panel lights
if the headlamps are not completely opened lorclosed The switches of the headlamp electrical sys-
tem are located behind the left headlamp operating,
mechanism.
MAINTENANCE AND ADJUSTMENTSHEADLAMP AIMING
The headlamps must be properly aimed in order to
obtain maximum road illumination and safety that
has been built into the headlighting equipment. With
the Guide T-3 type sealed beam units, proper aiming
is even more important because the increased range
and power of this lamp make even slight variations
from recommended aiming hazardous to approach-
ing motorists. The headlamps must be checked for
proper aim whenever a sealed beam unit is replaced
and after an adjustment or repairs of the front end
sheet metal assembly.
Regardless of method used for checking headlamp
aim, car must be at normal weight, that is, with gas,
oil, water, and spare tire. Tires must be uniformly
inflated to specified pressure. If car will regularly
carry an unusual load in rear compartment, or a
trailer, these loads should be on car when headlamps
are checked. Some States have special requirements
for headlamp aiming adjustment, and these require-
ments should be known and observed.
Horizontal and vertical aiming of each seal beam
unit is provided by two adjusting screws which move
the mounting ring in the body against the tension of
the coil spring. There is no adjustment for focus,
since the sealed beam unit is set for proper focus
during manufacturing assembly.
MAJOR REPAIRHEADLIGHT SWITCH
- OPEL 1900. MANTA
Removal1. Remove instrument cluster cover panel. See Sec-
tion H.
2. Compress retaining springs and pull switch out.
See Figure 1 F-
1.3. Pull multiple socket off switch.
Installation
1: Plug multiple socket in switch and push switch in
panel until clips lock in place.
2. Replace instrument cover and secure with two (2)
screws.

I2A- 21973 OPEL SERVICE MANUAL
GENERAL INFORlVlATION
CONTENTS
SubjectPage No.
DESCRIPTION AND OPERATION: (Not Applicable)
DIAGNOSIS: (Not Applicable)
MAINTENANCE AND ADJUSTMENTS:
PaintMaintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2A-2
ChromeMaintenance
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2A-2
StainRemoval
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2A-2
MAJOR REPAIR: (Not Applicable)
SPECIFICATIONS:
Bolt
TorqueSpecifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2A-4
Special Body Tools
. . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2A-5
MAINTENANCE AND ADJUSTMENTSPAINT MAINTENANCE
To remove heavy concentrations of road dirt and
grime, it is recommended that the car be washed
using an automotive shampoo or mild soap, and cold
to lukewarm water. Use of harsh soaps or detergents
is not advised. In areas where salt is used on the
roads during the winter months, more frequentwashing is recommended.
Use of cleaners and polishes are required if no high
luster is obtainable by waxing. To protect the paint
finish, sparingly apply several coats of wax. Each
coat should be thoroughly rubbed to remove any
surplus wax.
Once the car is properly waxed, road dirt may easily
be removed by use of cold to lukewarm water and a
sponge. Dry by use of a chamois.
CHROME MAINTENANCE
Chrome parts should be washed with water and a
mild detergent. If rust or salt corrosion should ap-
pear, they may be removed with Buick Rust Eraser
or equivalent. Do not use scouring powders or stiff
brushes.STAIN REMOVAL
Before attempting to remove spots or stains from
upholstery fabrics, determine as accurately as possi-
ble: (1) Nature and age of the spot or stain. (2) The
affect of stain removing agents on the color, struc-
ture and general appearance of the fabric.
For best results, stains should be removed from
upholstery as soon as possible after they have been
made. If they are allowed to stand for some time,
they often become set, and removal becomes more
diffxult and frequently impossible.
There are three basic types of acceptable’ cleaners
available to car owners: (1) Volatile cleaners, (2) Syn-
thetic detergents, (3) Neutral soap (non-alkaline).
The volatile cleaners are recommended since they
have great solvent powers for grease, oils and general
road grime. Synthetic detergents generally loosen
stains satisfactorily, however, the use of improper
type detergents (containing bleach) involves risk of
damage to the color or finish of fabrics.
Precautions For Cleaning FabricsDo not use laundry soap or detergents containing
bleaches. The use of these agents tends to weaken
fabric and to change its color. Do
not use too much
cleaning fluid. Some interior trim assemblies are pad-

ENGINE MECHANICAL AND MOUNTS6A- 15New inlet valves must not be refaced or lapped with
grinding compound.The correct angle for the intake
and exhaust valve head is 44 degrees.10. Install cylinder head.
11. Adjust valve clearance. See MAINTENANCE
AND ADJUSTMENTS.
7. Inspect valve guides. Worn or pitted guides can be
reamed to accept valves with oversize stems. Over-
size valves are occasionally used in production.
Oversize valves are marked
’ 1 u “2” or “A” and are
stamped into the valve stem end and also stamped
near spark plug hole. See Figure 6A-22.
Replacing Rocker Arm Studs1. When replacing rocker arm studs become
neces-
sary, remove air cleaner, rocker arm cover and
rocker arm.
8. Reseat valve seats in cylinder head in the following
sequence:
Intake
NOTE:The rocker arm studs are screwed into the
cylinder head. A tapered part of the stem serves to
a void stud loosening.With 45 degrees cutter, remove burnt structure until
a metallic bright seat is obtained. Lightly coat valve
head with red lead, insert it into guide and turn it
under light pressure several times back and forth.
Thereby a contact pattern is obtained and the seat
width can be measured. If valve does not seat per-
fectly all around, lightly recut valve seat to the estab-
lished seat width of
,049” - .059” with 30 degrees
correction cutter.
ExhaustThe directions for reconditioning intake valve seats
apply in principle also to exhaust valve seat recondi-
tioning with the exception that the valve seat width
should be
.063-,073 in. and different cutters are em-
ployed.
NOTE:
: OTse new valve seals whenever
valves are reconditioned.9. Lube valves with engine oil and reinstall valves,
valve springs, caps and cap retainers using J-8062.
Install valve spring with closely wound coils toward
cylinder head. See Figure
6A-24.2. Attach vise grip pliers to stud being removed and
remove from cylinder head.
3. Screw in new stud. Seat tapered part of stud by
striking stud end with a rubber hammer.
4. Place two turned down rocker arm nuts on
threaded part of stud.
5. Torque stud into cylinder head to 29
lb.ft.
Valve Lifter ServiceThe valve lifters can be removed after removing
rocker arm cover and rocker arms.No oversize lifters have been released due to the
insignificant wear of the valve lifters and cylinder
head guides.
Amply oil respective parts and install in reverse se-
quence to removal.
Carry out hydraulic valve lifter adjustment as ou-
tlined in MAINTENANCE AND ADJUST-
MENTS.
VALVE
I SPRING
CLOSE
WOUND
COILS
TOWARD
HEAD6A-24
Figure 6A-24 Valve SpringCONNECTING ROD BEARINGSA connecting rod bearing consists of two halves or
shells which are alike and interchangeable in rod and
cap. When the shells are placed in rod and cap the
ends extend slightly beyond the parting surfaces so
that when rod bolts are tightened the shells will be
clamped tightly in place to insure positive seating
and to prevent turning. Theends of shells must never
be tiled flush with parting surface of rod or cap.
If a precision type connecting rod bearing becomes
noisy or is worn so that clearance on crankpin is
excessive, a new bearing of proper size must be se-
lected and installed since no provision is made for
adjustment. Under no circumstances should the con-necting rod or cap be filed to adjust the bearing
clearance.

6A- 161973 OPEL SERVICE MANUALInspection of Connecting Rod Bearings and
Crankshaft JournalsRemove oil pan.
After removal of oil pan, disconnect two connecting
rods at a time from crankshaft and inspect the bear-
ings and crankpin journals. While,tuming crankshaft
it is necessary to
t&porarily reconnect the rods to
crankshaft to avoid possibility of damaging the jour-
nals through contact with loose rods.
If connecting rod bearings are chipped or scored they
should be replaced. If bearings
are in good physical
condition check for proper clearance on crankpins as
described under, checking clear$nce and selecting
replacement connecting rod beartngs.
If crankpin journals are scored or ridged, the crank-
shaft must be replaced, or reground for undersize
bearings, to insure satisfactory life of connecting rod
bearings. Slight roughness may be polished out withfine grit polishing cloth thoroughly wetted with en-
gine oil. Burrs may be honed off with a fine oil stone.
Use an outside micrometer to check crankpins for
out- of-round. If crankpins are mpre than
,002” out-
of- round, satisfactory life of new ,bearings cannot be
expected.
Checking Clearance and Selecting Replacement
Connecting Rod BearingsService bearings are furnished in standard size and
several undersizes. The clearance of connecting rod
(and crankshaft) bearings may be checked by use of
Plastigage, Type PG-1 (green), or equivalent, which
is soluble in oil.
1. Remove connecting rod cap with bearing shell.
Wipe off oil from bearing and crankpin journal, also
blow oil out of hole in crankshaft.
2. Place a piece of the plastic-type gauge material
Figure 6A-25 Checking Bearing
Cleatance WithPlastic-Type Gaugelengthwise along the bottom center of the lower bear-
ing shell (Figure 6A-25, view A), then install cap
with shell and tighten nuts to 36 lb. ft. Do not turn
crankshaft with gauge type material in bearing.
3. Remove bearing cap with bearing shell, the flat-
tened piece of gauge will be found adhering to either
the bearing shell or the crankpin. Do not remove it.
4. Using the scale printed on the envelope, measure
the flattened piece of gauge at its widest point. The
number within the graduation which closely corre-
sponds to the width of the gauge, indicates the bear-
ing clearance in thousandths of an inch. See Figure6A-25, View B.
5. The desired clearance with a new bearing is.0006”- .0025”. If bearing has been in service it is
advisable to install a new bearing if the clearance
exceeds .003”, however if bearing is in good condi-
tion and is not being checked because of bearing
noise, it is not necessary to replace the bearing.
6. After the proper size bearing has been selected,
clean off the gauge, oil thoroughly, reinstall cap with
bearing shell and tighten nuts to 36 lb. ft.
CRANKSHAFT BEARINGS AND SEALS
Replacement of Crankshaft BearingsA crankshaft bearing consists of two halves or shells
which are identical and are interchangeable in cap
and crankcase. All crankshaft bearings except the
rear main bearing are identical. The crankshaft end
thrust is taken up the rear (No. 5) main bearing.
Figure 6A-26 Engine Crankshaft Bearings
When the shells are placed in crankcase and bearing
cap, the ends extend slightly beyond the parting
sur-faces so that when cap bolts are tightened the shells
will be clamped tightly in place to insure positive

6A- 261973 OPEL SERVICE MANUAL
rear of cylinder head. Remove camshaft toward
front, supporting camshaft with one hand through
access hole and taking care not to damage bearing
surfaces. See Figure 6A-43.12345 6
I. OLD PRESSURE
4. COVER GASKET
RELIEF
~~- \SSEMBLY5. COVER 8 VALVE
ASSEMBLYVALVE I
2. TIMING CASE
6. COVER ATTACHING
3. OIL PUMP GEARS
SCREWS
123” 45Figure 6A-44 Oil Pump Components
1.CAMSHAFT
2. FRONT ACCESS HOLE
3. LATERAL ACCESS HOLE
4. CYLINDER HEAD
5. REAR ACCESS HOLEISA-43
Figure 6A-43 Removing Camshaft
Installation
1. Liberally lubricate camshaft journals and install
camshaft from front into cylinder head. Support
shaft through access hole in left side of head to pre-
vent damaging bearings.
2. Reinstall valve lifters, rocker arms and self- lock-
ing rocker arm nuts.
3. Install rear and side access plates.
4. Reinstall cylinder head.
OIL PUMP COVER AND GEARSRemoval and Installation of Oil Pump
Cover and Gears
1. Remove screws attaching oil pump cover assembly
to timing chain cover. Remove cover assembly and
slide out oil pump gears. See Figure 6A-44.
2. Wash off gears and inspect for wear, scoring, etc.
Replace any gears not found serviceable. Discard
pump covers scored by gear action. If pump housing
or distributor drive shaft bushing are worn (this is
only possible after a long service life), the timing case
together with all exchangeable pump parts have to be
discarded.In isolated cases, timing cases are installed in pro-
duction having
.008 in. oversize bores for pump gears
and shafts. Oversize bores may exist either for one or
both gears; these timing cases are identified by the
number “0.2” stamped into pump flange on left and-
/or right-hand side. Oversize replacement gears
should be selected according to Part Catalog specifi-
cations.
3. Liberally lubricate spindles and gear teeth and use
new cover gasket. Install oil pump cover.
If new gears are installed, their end clearance in a dry
pump housing should be checked with a straight
edge and a feeler gauge. The gears must not protrude
more than X04 in. over pump housing. See Figure6A-45.
FEELER
AUGESTRAIGHTIEDGE
Figure 6A-45 Checking Oil Pump Gear End Clearance