1973 OPEL GT-R service

IMPORTANT SAFETY NOTICE
Proper service and repair is important to the safe, reliable operation of all motor vehicles.
The service procedures recommended by BUICK and described in this service manual are
effective methods for performing service operations. Some of these service operationsrequire the use of tools specially designed for the purpose. The special tools should be used
when and as recommended.It is important to note that some warnings against the use of specific service methods that
can damage the vehicle or render it unsafe are stated in this service manual. It is also
important to understand these warnings are not exhaustive. BUICK could not possibly
know, evaluate and advise the service trade of all conceivable ways in which service might be
dbne or of the possible hazardous consequences of each way. Consequently, BUICK has not
undertaken any such broad evaluation. Accordingly, anyone who uses a service procedure ortool which is not recommended by BUICK must first satisfy himself thoroughly that neither
his safety nor vehicle safety will be jeopardized by the service method he selects.

1973
GTOPEL1900
MANTA
CHASSISSERVICE
MANUAL
This manual contains service informationfor the 1973 Opel 1900, Manta and GT
models. Refer to the introduction for
adescription of the arrangement of this
manual for locating desired information
easily.All
infotmation, illustrations and specifi-cations contained in this manual are basedon the latest product information aveil-able at the time of publication approval.
Therefore, the right is reserved to make
changes at any time without notice.TABLE OF CONTENTS
SUBJECT
I I
1ELECTRICAL
I I2FRAME AND BUMPERS
I I3SUSPENSION AND STEERING
I I4REAR AXLE
I I5BRAKES
I I
6ENGINE
I I7TRANSMISSION
I I
8CHASSIS SHEET METAL
I I
9ACCESSORIES

The 1973 Opel Chassis Service MayI has been completely revised with respect to layout, format and information content
in a” attempt
to provide you “The Technician” with a tiore logical and usable publication. An example of the new grouping
layout 6 exhibited on the preceding
page. Each wow is rubdivided as follows:
Grouo 1
_. _
Subiect IIContents.
0
General InformationIGeneral InformationLifting
Maintenance and Lubrication
1ElectricalBattery
Starting System
lgriition System
Charging System
Washers and Wipers
Lighting Systems
Signal SystemI
Instrument Panel
Gauges
Wiring Diagrams
2
Body and Bumpers:General Body InformationI
Frame & Body Mountings
Windows
& Window Moldings
DONS
Rear Compartment LidRoof &Sun Roof
Seat?., Interior Trim & Headlining
Bumpers.
3Suspension and Steering
Front Suspension
Steering Linkages1Front End Alignment
Steering Gear
Steering Column
Rear Suspension
Wheels and Tires
4
Propelley Shaft & Rear AxlePropeller Shaft & Central Joint
Differential
5Brakes ~Power Booster and Master Cylinder
Front Disc BrakeI
Rear Drum Brake
6EngineEngine Mechanical and Mounts
Cooling System
Fuel System
Exhaust Systems
Carburetor and Throttle Linkage
Emission Control Systems
Tune-up
7TransmissionClutch
Manual Transmission
Automatic Transmission
BChassis Sheet MetalHood, Fenders and Grille
9
Accessol;iesHeaterAirConditioning
Radio

INTRODUCTION
The 1973 Opel Service Manual includes information on the Opel 1900,
Manta and GT. It is organized to correspond with current servicing tech-
niques. The various chassis components and systems have been classified
into the nine (9) GROUPS.Every GROUP contains one or more SECTIONS. Each SECTION deals with aspecific version of a component or system.
The service information included in a SECTION is divided into five (5) basic
DIVISIONS. The titles of each DIVISION are:
Description and Operation
Trouble Diagnosis
Maintenance and Adjustments
Major Repair
SpLificaiions
A DIVISION contains one or more PARAGRAPHS which can be identified bytheir specific headings.
SUB-PARAGRAPHS are used when necessary for clarity or to provide distinc-tion between component procedures.
SPECIAL TOOLS
References are made throughout the Manual to special tool numbers, desig-nated by the prefix letter “J”. These tools are manufactured by the
Kent-
Moore Corporation, Inc. If equivalent special tools are not available locally,they may be obtained through:
Kent-Moore Corporation, Inc.
28635 Mound Road
Warren, Michigan 46092LOCATING DESIRED INFORMATION
To locate any desired information, locate the proper GROUP listed on the
second page of the Manual. Bend the Manual until the black tab on the first
page of the GROUP can be seen in line with the GROUP title on the secondpage. The first page of the GROUP lists the SECTIONS contained therein.
Turn to the proper SECTION, locate the desired DIVISION and note the
PARAGRAPH containing the information you are seeking.

sOA- 1973 OPEL SERVICE MANUAL _
MODEL DESIGNATIONSOLll - OPEL 1900 2DR SEDANOL60
-OPEL 1900 4DR SEDAN
OL15 OPEL 1900 3DR WAGON
MANTA 2 DR SPT. CPE.
OL77 -
cMANTA 2DR RALLYE SPT. CPE.
MANTA LUXUS 2DR SPT. CPE.1 OY07 GT 2DR SPT. CPE.
+
1VEHICLE IDENTIFICATION NUMbER
OL77N
GM Model Designation
I
Engine Code
Model Year
Assembly Plant
c9123456
ilGENERAL SPECIFICATIONS
MODEL AI(ID
NAME I
Opel
1900
Manta
51.2DrSedan
53.4DrS+n
54.3DrWqgon
57. 2Dr Spi. Cpe.57R- 2Dr R&ye Spt. Cpe.
Manta
LUXUS57L. 2Dr Lu+sSpt. Cpe
GT
77. 2Dr Splf. Cpe.
IVVHEEL- FRONT REAR CURBOVERAL
BASETREAD TREAD WEIGHT WIDTH LENGT,
2138=
2183*164.6
2227l
2183l
95.752.452-64.3
2205l
171
2183l
49.450.62120*62.2161.9l Add 44
Ibs. for auto. trans.
Figure OA-4 General InformationHElGHl
52.6
53.3
51.3
47.4PAINTVehicle Identification Plate when that type of paint
Two types of paint are again useh for 1973, Enamelis used. Paint supplied by U.S. suppliers for repair
work is applicable on either type paint except that a
and Acrylic. The word “Acrylic’! is embossed on thedifferent match formula is required.
/

CC-61973 OPEL SERVICE ‘MANUAL
LUBRICATION AND GENERAL MAINTENANCE
Every 4 months or 3,OW mile3~1*Engine OilEMISSION CONTROL MAINTENANCE
Every 24 months or31 1Engine Conpression
24,ooO~ 32heI cap, Tank and LinesEVsN
24.m milesI 33I Air Cleaner E,eme”tI
‘Alsa an Emision Control Servicel Also a Ssfarv Servicemc21Figure OC-2 1973 Maintenance Schedule

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.