1973 OPEL GT-R engine coolant

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.

6A. 61973 OPEL SERVICE MANUALDIAGNOSIS
EXCESSIVE OIL CONSUMPTION
ConditionCorrectionExternal Oil Leaks at:Tighten attaching bolts. If leaks
Rocker Arm Coverspersist, remove cover (or pan),
Crankcase Front Covercheck sealing surfaces for burrs
Oil Pan and Gasketor scoring, replace gasket, and
seal bolts with silastic sealer or
equivalent. Make sure oil level
,is not overfull.
Improper Reading of Dip-Car may not be level when taking r
StickInsuffIcient oil “drain-back” time
after stopping engine (three
minutes must be allowed). Dip-
stick may not be completely pushed
down against stop. Dipstick may
be bent.
Oil Viscosity Too LightUse recommended SAE viscosity for
prevailing temperatures.
Continuous High-SpeedAt speeds above 60 mph, increased
Drivingsumption can be expected with any
Inform customer of this fact.
High-Speed DrivingWhen principal use of automobile i
Following Normal Slowcity driving, crankcase dilution f
Speed City Drivingcondensation occurs. High speed a
temperatures will remove water,
resulting in what appears to be
rapid lowering of oil level.
Inform customer of this fact.
Piston Rings NotAllow engine to accumulate at leas
“Broken In”
4,OCO miles before attempting any
engine disassembly to correct for
oil consumption.
NOISY VALVES AND LIFTERSIf the preceding check indicates valve mechanism is
abnormally noisy, remove the rocker arm cover so
that the various conditions that cause noise may be
The noise level of the valve mechanism cannot bechecked. A piece of heater hose of convenient length
properly judged where the engine is below operatingmay be used to pick out the particular valves or valve
temperature when the hood is raised, or when thelinkages
thit are causing abnormal noise. With the
valve rocker arm covers are removed.engine running at a speed where the noise is pro-
nounced; hold the end of hose to an ear and hold
Before attempting to judge valve noise level, the en-other end about
l/2 inch from point of contact be-
gine must be thoroughly warmed up (at least 20tween rocker arm and valve stem. Mark or record the
minutes of operation at
1200 to 1500 RPM) to stabil-noisy valves for investigation of following causes:ize oil and coolant temperatures and bring all engine
parts to a normal state of expansion. When the
en-1. Sticking, Warped, or Eccentric Valves, Worngine is warmed up, listen for engine noise while
sit-Guides Sticking valves will cause irregular engine
ting in the driver’s seat with the hood closed. Run theoperation or missing on a low speed pull and will
engine at idle and at various higher speeds.usually cause intermittent noise.

6A- 8 1973 OPEL SERVICE MANUAL
Actual adjustment is made by backing off adjusting
nut at the rocker arm until clearance exists between the valve stem, rocker arm, and lifter. Then slowly
tighten adjusting nut until clearance is eliminated.
When clearance is eliminated, turn adjusting nut one
full turn (clockwise). This positions the hydraulic
piston of the hydraulic lifter mid-point in its total
available travel, and no further adjustment is re-
quired.
MAJOR REPAIR
ENGINE ASSEMBLY REMOVAL AND
INSTALLATION
Removal (Opel 1900 and Manta)’
The engine assembly on the Opel 1900 and Manta
can be removed together with the transmission
through the top of the engine compartment.
1. Remove hood (scribe hood hinge to hood mount-
ing location).
2. Disconnect battery negative cable.
3. Drain coolant at lower radiator hose.
4. Remove upper and lower radiator hoses.
5. Remove radiator and fan
shrbud.
6. Disconnect heater hoses.
7. Disconnect brake booster
vacuum hose.
8. Remove air cleaner.
9. Disconnect electrical connections and accelerator
linkage. 10. Remove console.
11. Remove shift lever boot, plate, and shift lever.
12. Raise car on hoist.
13. Disconnect fuel line at pump.
14. Remove front stone shield.
15. Disconnect speedo-cable, back-up light switch,
and clutch cable.
16. Remove drive shaft. I
17. Disconnect exhaust pipe
ar$l bell housing sup-
port.
18. Disconnect transmission support. See Figure
6A-7. 19. Remove engine mount bolts. See Figure
6A-8.
20. Attach hoist chains.
21. Lift engine and transmission assembly out of car.
Figure 6A-7 Transmission Support Bolts . Opel 1900
and Manta Series
Figure
6A-B Engine Mount Bolts - Opel 1900 and
Manta Series
Removal (GT)
The removal and installation of the 1.9 liter engine is only possible towards the floor and from below
Fig, 6A-9 Left Front Engine Suspension with Cross
Member (GT)

ENGINE MECHANICAL AND MOUNTS6A- 9
The engine does not rest on the front suspension
cross member as in the Opel 1900 and Manta but on
a separate cross member. On removal and installa-
tion of the engine the front suspension cross member
need not be detached.
Fig. 6A-10 Right Front Engine Suspension with Cross
Member
(GT)1. Disconnect battery negative cable,
2. Remove air cleaner.
3. Drain radiator coolant by disconnecting lower
radiator hose. Disconnect upper radiator hose. See
Figure 6A-11. Radiator need not be disconnected.
4. Disconnect all electrical connections:
a. Coil wire to distributor.
b. Wires from alternator. Remove unit and bracket.
c. Battery positive cable at starter switch.
d. Oil pressure switch wires at cylinder block.
e. Wires from starter solenoid.
5. Remove vacuum hoses at tee mounted to intake
manifold. Remove tee from manifold to avoid inter-
ference during engine lowering.
6. Remove throttle linkage and carburetor.
7. Disconnect heater hoses.
8. Disconnect water valve bracket to manifold,
9. Remove gear shift lever.
10. Using suitable equipment lift up engine so that
front engine mounts are somewhat relieved.Figure 6A.1
1 Radiator Hose Clamp Location
11. Raise vehicle, both front and rear end. A two post
axle type hoist
IS recommended for this operation.
12. Disconnect fuel line at fuel pump and plug. Be
sure fuel line is disconnected from any engine and
transmission clips.
13. Disconnect speedometer cable from transmis-
sion.14. Disconnect clutch cable.
15. Disconnect drive shaft at rear universal joint and
remove.
16. Disconnect exhaust at manifold.
17. Remove tailpipe and mufIler hangers.
18. Remove ground strap from engine to side rail.
19. Detach transmission cross member from trans-
mission and frame. See Figure 6A-12.
20. Detach engine cross member from engine and
frame.21. Carefully lower engine and transmission and
remove from underneath vehicle.

6A- 121973 OPEL SERVICE MANUALINTAKE AND EXHAUST MANIFOLD REMOVAL
AND
INSTALLATION
Removal1. Disconnect battery.
2. Remove air cleaner.
3. Disconnect throttle linkage at carburetor.
4. Disconnect vacuum advance line at carburetor.
5. Remove fuel line at carburetor inlet.
6. Remove positive crankcase ventilation hose at
rocker arm cover.
7. Disconnect E.G.R. lines from carburetor and in-
take manifold.
8. Disconnect exhaust pipe.
9. Remove six bolts attaching manifold assembly to
cylinder head and remove manifold and carburetor
as an assembly. Discard manifold gasket.
To separate intake and exhaust, manifold, remove
carburetor and four bolts using Tool J-23016, attach-
ing intake manifold to exhaust manifold. Always in-
stall a new manifold intermediate gasket when the
manifolds are separated.
Installation1. Install new manifold gasket and place manifold in
position.
2. Install manifold bolts. New manifold to cylinder
head gasket must be installed whenever a manifold
is removed.
3. When installing the manifold, start with the No.
1 and No. 2 bolts. See Figure 6A-16. Gradually
tighten both bolts until snug. Then continue with the
rest of the bolts in the sequence illustrated in Figure6A-16. Torque bolts to 33 lb. ft.
Figure 6A-16 Manifold
Bolt Tightening Sequence4. Connect parts removed in Steps 1 thru 8 above.
CYLINDER HEAD REMOVAL AND INSTALLATION
Removal1. Drain coolant from radiator and block. Loosen
drain plug on right side of engine to avoid coolant
entering into cylmder bores. Drain plug is located onthe right rear of cylinder block above oil pressure
switch.2. Remove hoses from thermostat housing. Collect
coolant as it contains anti-freeze.
3. Remove 6 intake and exhaust manifold attaching
bolts and swing assembly aside.
4. Remove spark plug wires from plugs.
5. Remove bracket bolt holding spark plug wires
away from cylinder head.
6. Remove rocker arm cover.
7. Remove 10 cylinder head bolts using 12 MM ser-
rated drive J-22915, and 2 cylinder head to timing
chain cover bolts with a 6MM hex head wrench. See
Figure 6A- 17.
Figure 6A-17 Serrated Bits
8. Remove three bolts attaching plate to front of
cylinder head.
9. Remove plastic screw from end of camshaft.
10. Remove 3 bolts attaching camshaft sprocket to
cylinder head. Slide sprocket off of camshaft and
remove head. Place head on bench supported at each
end by a block of wood to prevent damage to valves.
Installation1. Install in reverse procedure to removal, paying
particular attention to the following:

RECESSES VERTICAL FOR
REMOVAL OF LEFT ROW OF
CYLINDER HEAD BOLTS6A-16
Figure 6A-18 Recesses in Camshaft
2. Clean piston tops and combustion chambers.
Thoroughly clean all gasket surfaces on the cylinder
block and cylinder head.
3. Lightly lubricate cylinder walls with engine oil.
Install coolant passage rubber gasket ring in timing
case. See Figure 6A-19.I. TIMING CHAIN
2. CAMSHAFT SPROCKET
3. SPROCKET TIMING MARK
4. TIMING CASE5. SUPPORT TIMING MARK
6. SUPPORT
7. CYLINDER BLOCK
6. RUBBER GASKET RING6A-19
Figure 6A-19 Coolant Passage Rubber Gasket Ring in
Timing CaseENGINE MECHANICAL AND MOUNTS
6A- 13
4. Apply silastic sealer or equivalent to both sides of
the cylinder head gasket where the gasket mates with
the timing chain cover, place new cylinder head gas-
ket onto cylinder block.
5. Install cylinder head. Be careful to place head
squarely over guide pins.
Rotate camshaft so that recesses are in vertical posi-
tion to allow installation of left row of bolts.
6. Install 10 head bolts. Tighten the bolts a little at
a time in the sequence shown in Figure 6A-20. Give
bolts a final torque in the same sequence. Torque to
72 lb. ft. (cylinder head cold). Use same procedure
for cylinder head to timing chain cover bolts with
final torque at 17
lb.ft. See Figure 6A-20. These
torques apply to lightly oiled threads.
Figure 6A-20 Cylinder Head Bolt Tightening
sequence7. Slide camshaft sprocket with assembled chain onto
camshaft and guide pin and fasten with bolts. Install
nylon adjusting screw. After sprocket has been at-
tached to camshaft, recheck alignment to see that
chain has not slipped. Close front access hole.
8. Check camshaft end clearance between cover and
nylon screw with feeler gauge. Clearance should be
.004” - .008” Excess clearance can be eliminated by
carefully readjusting cover with a suitable drift.
Reconditioning Valves and Guides1. Remove cylinder head. Place on clean surface.
Place head on bench supported at each end by a
block of wood to prevent damage to valves.
2. Using suitable spring compressor, such as J-8062,
compress valve spring and remove cap retainers. Re-
lease tool and remove spring and cap. See Figure 6A-
21.3. Remove valves. Place valves in numerical order so
that they can be reinstalled in original location.
4. Remove all carbon from combustion chambers,
piston heads, and valves. When using scrapers or

GA. xl1973 OPEL SERVICE MANUAL
Valve Seat and Correction Angle in Cylinder Head
Intake
Valve Seat Angle ..,._,..__....,,..,,,..,.,.,.,..............,............................................................... 45”Outer Correction
.,,,.,,._.,._..___,,,.,,,,,.......,,.,..,...,,..,..,,..,,..,,,.............................................. 30”
Exhaust
Valve Seat Angle
,,,.,,.__,.__..___.,..,,..,...,,....,..,..,..,,..,..,...,..,,,...,,......................................... 45”
Outer Correction
.,,..,,...,._.,.__....,,,.....,,,........................................................................... 30”
Valve Face Angle
,,..,,,..,.__..__.._..,,,..,,...,,......,.,..,..,..,,.,,,..,..,,,..,,,..,,,...,,................................ 44”Valve Seat Width in Cylinder Head
Intake
. . . . . . . . . . .._..._._.................,,..,.....,,..,............,...,..,,,..,,..,,...,,...,,,..,..................049-,059 In.
Exhaust
.,..,,,..,,.___..,,..,,...,..,,,..,,...,,...,,...............,,..,,..........,,....,,...,..................... .063-,073 In.Valve Head Contact Area
,,..,,,..,,___.__.,,..,,..,.,,..........,...,,..,,............,,,...,....... Aim at Centricity
Valve Clearance at 176°F. Coolant and 140°F. to 176”
Oil Temperature
Intake and Exhaust
_.,,..,,,,,,..,,....,...,,,.,.,,,.,..........................,,,..,,,,.... Zero Plus One Turn
Cranking MechanismMax. Permissible Out-of-Roundness of Connecting Rod Bearing
Journals
.....................................................................................................................OC02 In.
Max. Permissible Taper of Connecting Rod and Crankshaft Bearing
Journals
.....................................................................................................................ooO4 In.
Max. Permissible Radial Runout of Center Main Bearing
JournalsWhenSupportedinEndBearings
...........................................................0012In.Max. Permissible UnparalYelism of Connecting Rod Bearing
Journals When Crankshaft is Placed in V-Blocks so That
Main Bearing Journals Next to Each Other Are Supported
................................0005 In.
Max. Permissible Runout of Crankshaft to Flywheel
Contact Area
...........................................................................................................0008 In.
Crankshaft End Play
.........................................................................................GOl7-.CO61 In.
MainBearingClearance
.....................................................................................ooO9-.@I25In.Connecting Rod Bearing Clearance
.................................................................ooO6-.0025 In.
Connecting RodEnd PlayonBearing Journal
...............................................0043-.0095In.Connecting Rod Bearing Length
.......................................................................7785-.7992 In.
CrankshaftThrustBearingLength
..............................................................................1.08In.
Valve MechanismCamshaft Bearing Clearance
.................................................................................OOl-,003 In.
Camshaft End Play
...............................................................................................004-038 In.
Max. Permissible Radial Runout of Camshaft Center Bearing
- Camshaft Supported in Outer Bearings................................................................,001 In.
ValveLifter Clearance in Cylinder HeadBore
...............................................0003-.OOl3In.
Engine Lubricating SystemOil Pump Gear Backlash
......................................................................................0%.008 In.
Oil Pump Gear End Play in Housing
........................................Gears Protruding Over Edge
of Housing: Not More Than
,004 In.
Clearance of Spindle in Bore of Oil Pump Driven
Gear
...............................................................................................................OCO3-.0015 In.
Clearance Between Oil Pump Drive Gear and
Bushing
.........................................................................................................00035-.OOl5 In.
Oil Pump Relief Valve Spring Pressure at a Spring Length
of
.8 In..................................................................................................................44-.66 Lbs.