ignition OPEL GT-R 1973 Workshop Manual

3E- 481973 OPEL SERVICE MANUAL
Figure 3E-24 Removing Electrical Unit
Before installing electrical unit be sore unit is in
RUN position. Using a Philips screwdriver, turn in-
ner sleeve to the tight until a springy resistance is
felt. See Figure 3E-25.Figure 3E-25 Checking for RUN Position
2. Install ignition switch electrical unit. See Figure
3E-24.3. Install housing cover by attaching with three (3)
screws.4. Install steering lock retaining screw. See Figure
3E-20.5. Reconnect ignition (white) wire set plug.6. Install direction signal switch lever.
7. Install ignition lock cylinder. See previous para-
graph in this section.
REMOVAL AND INSTALLATION OF UPPER
STEERING BEARING AND/OR DIRECTION SIGNAL
SWITCH1. Remove ignition switch and steering lock, see
previous paragraph in this section.
2. Disconnect direction signal (black) wire set plug.
3. Remove wires from connector plug making certain
to note location of each.
4. Remove screws and direction signal housing and
switch assembly. See Figure
3E-26.
..3E-26
Figure 3E-26 Removing Direction Signal Switch
Assembly5. To remove upper bearing, pull horn wire out of
bearing housing and pry out bearing assembly using
a flat screwdriver. See Figure
3E-27.
Installation1. If upper bearing has been removed, install by using
the thumbs of both hands being sure to line bearing
up with notched portion of housing.
2. Install direction signal housing and switch assem-
bly. See Figure 3B26.
3. Reposition wires into connector plug and connect
direction signal wire set.

GT STEERING COLUMN ASSEMBLY3E- 49
4. Install ignition switch and steering lock
REMOVAL AND INSTALLATION OF STEERING
COLUMN LOWER BEARING
The following is with steering column assembly
removed.
1. Remove steering wheel.
2. Remove screws securing lower bearing housing to
mast jacket.
3. Remove steering shaft together with universal
joint and bearing and housing.
4. Remove universal joint from shaft. See Figure 3E-28.Figure 3627 Removing Upper Bearing
SERRATED SOCKET
“‘*E.Z<~lh I’
I//
11 uBEARING HOUSINGy
SE-28Figure 3E.28 Removing Lower Bearing
5. Remove bearing retainer snap ring and remove
bearing.
Installation3. Install steering shaft, together with universal joint
bearing and housing to mast jacket. Serrated socket
head screw must be installed on
tm side of steering
column assembly. See Figure 3E-2\.
1. Install bearing and bearing retainer snap ring.
2. Install universal joint and torque to 22
Ib.ft.4. Install steering wheel. On installation of steering
wheel, make sure that with flats of lower portion of
universal joint horizontal, the center steering wheel
spoke must be vertical.

ENGINE MECHANICAL AND MOUNTS6A- 231. NOTCH IN PISTON HEAD
POINTING TOWARD THE FRONT
2. OIL HOLE IN CONNECTING ROD
POINTING TOWARD THE RIGHT
(MANIFOLD SIDE)
3. NOTCH IN CONNECTING ROD
CAP POINTING TOWARD THE
REAR6A-36
Figure
6A-39 Piston and Rod Assemblyby oompressing the rings with a “wrap around” com-
pressor.9. Select a new connecting rod bearing, if necessary.
Otherwise install cap with bearing lower shell on rod
and tighten bolt nuts to 36
lb.ft. torque.
10. Install all other piston and rod assemblies in same
manner. When piston and rod assemblies are prop
erly installed, the oil spurt holes in the connecting
rods will be facing right.
11. Check end clearance between connecting rods in
each crankpin using feeler gages. Clearance should
be between
.0043” and .0095”.
12. Install cylinder head. Torque 10 cylinder head
bolts to 72 lb.ft (cold), and 2 cylinder head to timing
chain cover bolts to 17
lb.ft.13. Install new oil pan gasket by first installing flange
gasket with tabs in slots in rear main bearing cap and
engine front cover. Then install rubber strips in
grooves in rear main bearing cap and engine front
cover. Install oil pan, torquing bolts to 5 lb.ft.
14. Install (Opel
1900 and Manta) front suspension
assembly. (GT) Install engine suspension cross mem-
ber.After installation of new pistons and rings, care
should be used in starting the engine and in running
it for the first hour. Avoid high speeds until the parts
have had a reasonable amount of break-in so that
scuffling will not occur.
TIMING CHAIN COVER AND TIMING CHAIN
Timing Chain Cover Removal
1, Support engine in vehicle as outlined under Engine
Oil Pan Removal and Installation.
2. Remove radiator and shroud assembly
3. Remove cylinder head.
4. Remove alternator belt and remove alternator
mounting bracket.
5. Remove fuel pump
6. Remove ignition distributor.
7. Remove chain tensioner assembly out of timing
cover.8. Remove crankshaft pulley bolt and remove pulley.
9. Remove water pump assembly.
10. Remove oil pan
11. Remove timing chain cover bolts. One bolt is
covered by the water pump. See Figure 6A-39.
12. Pull off sprockets with chain. Put a paint mark
Figure 6A-39 Bolt Behind Water Pump

CARBURETOR AND THROTTLE LINKAGE6E- 49DIAGNOSIS
CARBURETORCondition I
Hesitation or Stall Upon Light AccelerationCorrection
1. Check spark plugs and plug gap. Plug gap should
be
,030 in.
2. Check dwell and timing.
3. Adjust carburetor.
4. Accelerator pump should discharge fuel between
throttle plate and venturi wall with engine off. If aim
is not correct, use needlenose pliers to slightly bend
nozzle so proper aim is achieved. See Figure 6E- 10.
CORRECT ACCELERATOR
PUMP DISCHARGE
NOZZLE AIM
\Figure 6E-10 Pump Shot Aim
Road test car. If hesitation still exists, check for the
folI0 wing:1. Plugged accelerator pump discharge nozzle.2. Dirt in accelerator pump circuit.
3. Defective inlet check ball.
4. Defective accelerator pump pressure relief valve.
5. Defective accelerator pump diaphragm.
6. Maladjusted accelerator pump linkage.
Condition II
Hard Start Afier Hot Soak
CorrectionPerform Steps l-4 in Condition I.
Condition Ill
Hard Start When Engine Is Cold
Correction1. Align groove on choke cover with pointer on
choke housing. See Figure
6E-17.2. Set fast idle.
3. Replace distributor points if pitted.
4. Check spark plugs and gap at
,030.5. Set dwell and timing.
If above procedure does not correct problem, replace
with new automatic choke assembly.
Condition IV
Rough, Erratic, or No Idle
Correction1. Check spark plugs and gap at
,030.2. Check dwell angle and ignition timing.
3. Clean idle jet and passages with air hose. See Fig-
ure
6E-5.4. Check manifold to head bolt torque. Should be 33
lb.ft.5. Check automatic choke linkage alignment.
6. Adjust carburetor.

6E- 501973 OPEL SERVICE MANUALMAINTENANCE AND ADJUSTMENTS
IDLE SPEED ADJUSTMENT
Note:
Idle speeds of 600 to 800 R.P.M. are normal
for engines with less than
3,ooO miles.Prior to making any adjustment to the carburetor,
the following items must be checked for proper oper-
ation and/or setting:
1. Valve Adjustment (Hydraulic lifters can be im-
properly adjusted.)
2. Dwell Angle.
3. Ignition Timing.
4. Spark Plug Gap.
5. Exhaust Gas Recirculation Valve (See “Check-
ing” under EXHAUST GAS RECIRCULATION
SYSTEM.)
After it has been ascertained that the above items are
properly adjusted and operating correctly and idle
R.P.M. is still not within specifications, proceed as
follows:
1. With air cleaner installed, run engine until normal
operating temperature is reached.
2. Remove plastic caps from the idle mixture screw
and air speed screw. See Figure
6E-11.Figure
6E-1 1 Carburetor Adjusting Screws
3. To raise R.P.M., turn air speed screw counter-
clockwise. To lower R.P.M., turn air speed screw
clockwise, thereby reducing the amount of air going
through the system.4.
Ad,just idle mixture screw until highest R.P.M. is
obtained. Alternately adjust idle mixture screw and
air speed screw until R.P.M. is obtained that is 50
R.P.M. higher than the desired final setting. This is
to be accomplished with the idle mixture screw at
best idle.
5. Turn idle mixture screw clockwise (lean) until a
decrease of 50 R.P.M. is obtained. The idle R.P.M.
will
n.ow be within specifications and proper emis-
sion control maintained.
6. Install red plastic caps over the air speed screw
and idle mixture screw.
Basic Idle AdjustmentA basic idle adjustment is to be made only if engine
idle R.P.M. correction does not result in correct idle
R.P.M. setting and engine has more than
3,OOO miles
of operation. If necessary, proceed as follows:
1. Remove plastic cap from the throttle valve stop
screw. See Figure
6E-11.2. Place the Manometer (J-23951) in a vertical posi-
tion. Turn the 2 vents on top open to equalize pres-
sure and balance gauge to read zero. With engine
idling, unplug the vacuum advance hose from the
carburetor and connect the manometer hose in its
place. See Figure 6E- 12.
Figure 6E-12 Throttle Plate Calibrator J-23951
Installed3. If the manometer does not read 1 to 8 inches of

TUNE-UP
ALL MODELS
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Purpose of a Tune-Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . .DIAGNOSIS: (Not Applicable)
MAINTENANCE AND ADJUSTMENTS:
EngineTune-UpMechanicalOperations. . . . . . . . . . . . . . . . . . . .
EngineTune-UpInstrumentChecks. . . . . . . . . . . . . . . . . . . . . . . . . . . .MAJOR REPAIR: (Not Applicable)
SPECIFICATIONS:
Tune-Uo Soecifications and Adjustments
. . . . . . . . . . . . . . . .Page No.6G-65
6G-6566-6766-68
DESCRIPTION AND OPERATION
PURPOSE OF TUNE-UP
The purpose of an engine tune-up is to restore powerand performance that may have been lost through,
loss of adjustment, wear, corrosion, or deterioration
of one or more parts or units. In the normal operat-
ion of an engine, these changes take place gradually
at quite a number of points so that it is seldom advis-able to attempt an improvement in performance by
correcting one or two items only. Time will be savedand more lasting results will be assured by following
a definite and thorough procedure of analysis and
correction of all items affecting power and perform-
ance. Because of Federal laws, limiting exhaust emis-sions, it is even more important that the engines
tune-up is done accurately, using the specifications
listed and the tune-up sticker found in each engine
compartment.
Economical, trouble free operation can better be as-sured if a complete tune-up is performed at first 4
months or
6,ooO miles of operation - then at 12
month or 12,000 mile intervals.
The parts or units which affect power and perform-
ance may be divided, into three groups (1) compres-sion, (2) ignition and (3) carburetion. The tune-up
procedure should cover these groups in the order
given. While the items affecting compression and
ignition may be handled according to individual
preference, correction of items in the carburetiongroup should not be attemplcu
ulllll all items in
compression and ignition have been satisfactorily
corrected.
MAINTENANCE AND ADJUSTMENTS
ENGINE TUNE-UP OPERATIONS
CompressionTo make sure hydrocarbon and carbon monoxide
emissions will be within limits, it is very important
that the adjustments be followed exactly.
The suggested procedure for engine tune-up is as
follows:1. Remove all spark plugs.
2. Position throttle and choke valve in full open posi-tion.
3. Connect jumper wire between distributor terminalof coil and ground on engine to avoid high tension
sparking while cranking engine.
4. Hook up starter remote control cable and turn
ignition switch to “on” position.
5. Firmly insert compression gage in spark plug port.Crank engine to obtain highest possible reading.

6G- 661973 OPEL SERVICE MANUAL
6. Check compression of each cylinder. Repeat
compression check and record highest reading ob-
tained on each cylinder during the two pressurechecks.The recorded compression pressures are to be con-
sidered normal if the lowest reading cylinder is more
than 75 percent of the highest reading cylinder. See
the following example and the “Compression Pres-
sure Limit Chart.” See Figure
6G-2.Seventy-five percent of 140 (highest) is 105. Thus,
cylinder No. 4 is less than 75 percent of No. 3. This
condition, accompanied by low speed missing, indi-
cates an improperly seated valve or worn or broken
piston ring. See Figure 6G-1.
23
I
SO-1Figure 6G-1 Example of Compression Check
7. If one or more cylinders read low, inject about a
tablespoon of engine oil on top of pistons in low
reading cylinders through spark plug port. Repeat
compression check on these cylinders.
a: If compression improves considerably, rings are
lV0*tl.b. If compression does not improve, valves are stick-
ing or seating poorly.
c. If two adjacent cylinders indicate low compression
and injecting oil does not increase compression, the
cause may be the head gasket leaking between the
cylinders. Engine coolant and/or oil in cylinders
could result from this defect.
Compression Pressure Limit ChartThis chart may be used when checking cylinder com-
pression pressures. It has been calculated so that the
lowest reading number is 75 percent of the highest
reading number. See Figure 6G-2.
EXAMPLE: After checking the compression pressures
in all cylinders, it was found that the highest pressure
obtained was 182 psi The lowest pressure reading
was 145psi.
By locating 182 in the maximum col-
umn, it is seen that the minimum allowable pressure
r-.__MAXIMUM
PRESSURE
POIJNWW. INCH
--
134
136
138
140
142
146148
150
152
154
156
158160lb2
164166168170172
174
176
178
180182184
186MINIMUM
PRESSURE
POUNDS/
SQ. INCHHAXIMUM
‘RESSURE
‘OUNWiQ. INCHMINIMUM
PRESSURE“OUNWX?. INCH
101188I41I02190142104192144105194145107196147II0198148Ill200150
113202151
114204153
115206154
117208156118210157120212158
121214160123216162
124218163
126220165127222166129224168131226169132228171133230172
135232174136234175138236177140238178
Figire 6G.2 Compression Pressure Limit Chart
is 136psi. Since the lowest reading obtained was 145
psi,
the car is within limits and the compression is
considered satisfactory.
Spark Plugs1. Inspect, clean and regap or replace spark plugs as
required. Correct gap is
,030.2. Install spark plugs. Tighten to 30 lb.ft.
Secondary Ignition System1. Inspect ignition cables for broken, swollen or
deteriorated insulation.
2. Check terminal ends and condition of rubber
boots. Replace as required.
3. Inspect the condition of the distributor cap and
rotor.
4. Clean the ignition coil and inspect for cracks or
carbon paths which could cause high voltage leak-
age.
Distributor Contact Points1. Inspect distributor contact points and replace or
adjust as necessary
(.016 gap).

2. If inspection of contact points indicates excessive
burning, pitting or wear, check condenser and re-
place if necessary.
3. Inspect all connections and wires in the primary
ignition circuit. Correct any abnormal conditions
found.Carburetor1. Clean fuel strainer in fuel pump. To prevent fuel
leakage in pump, disconnect “IN” line from pump
and raise end above fuel level. The in-line fuel filter
should be replaced every 12,000 miles or every 12
months.
2. Check for freedom of choke valve operation and
clean shaft if necessary, with suitable solvent.
3. Inspect throttle cable or linkage bracket and re-
turn spring for wear. With helper depressing acceler-
ator pedal to floor, check for wide open throttle.
Adjust accelerator pedal height so wide open throttle
is obtained when pedal is within
l/2 inch from floor.
Lubricate linkage pivot points with engine oil.
Air CleanerCheck paper element every 6,000 miles and replace
every
24,ooO miles. If a vehicle is operated in dusty
territory, check condition of air cleaner element
more frequently and replace if necessary.
Fan Belt1. Inspect belt for wear, cracks or frayed points.
Replace and/or adjust as necessary. Specified ten-
sion for belt using Gauge J-23600 is 45 lbs.
Cooling System1. Inspect the radiator, water pump, cylinder head
areas and all radiator and heater hose connections
for evidence of engine coolant leaks.
2. Inspect all hoses for deterioration from gas and oil
contact. Correct as required.
Inspection should be made with engine operating at
normal temperature, cooling system completely
filled, temperature control lever fully open and nor-
mal pressure in the system. Normal pressure should
be 13.2 to 15.2 psi.
Engine Lubrication SystemInspect engine for evidence of oil leakage. Correctany abnormal condition with sealastic or new seals
and gaskets.
Battery
1. Inspect battery, battery mount and cables and
check electrolyte level. Proper level should be just
above the cell plates.
CAUTION:Do not over fill.
2. Determine the serviceability of the battery by ap-
plying the 421 Battery Test.
Positive Crankcase VentilationClean crankcase ventilator metered orifice in the in-
take manifold fitting every 6,000 miles. Also all hoses
and fittings should be inspected, cleaned and re-
placed, if necessary.
To clean, remove rubber hose from metered orifice
and apply air pressure to orifice to remove any for-
eign particles that may be trapped.
Valve Lifter AdjustmentRefer to Engine Mechanical and Mounts section for
valve lifter adjustment procedure.
Engine Tune-Up Instrument ChecksThe following instrument checks and adjustments
serve as a final check on engine condition. These
checks may discover some new problems that may
not have been obvious before. The engine is also
given its final adjustments that will assure maximum
performance, reliability, and proper emission con-
trol.
Refer to Electrical Group for checking procedures of
the following:
Cranking Voltage Check
Ignition Timing
Distributor Advance
Ignition Output
Secondary Resistance
Current Output and Voltage Setting
Idle Speed and Mixture AdjustmentsRefer to carburetor section.

6G- 68 1973 OPEL SERVICE MANUAL
SPECIFICATIONS
TUNE-UP SPECIFICATIONS AND ADJUSTMENTS
Voltage Regulator
Voltage Regulator Setting in Volts at2500 Engine RPM. . . . . . . . . . . . . . . . . . . . . .14+.5
Ignition Coil
Ignition Coil Current Draw, Amperes at 12.5 Volts
Engine Stopped
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . .3.8
EngineIdling. . . . . . . . . . . . . . . . . .._.....................................................................\
........................... 2.3
Total Advance (Centrifugal and Vacuum), Engine Degrees at 3600 Engine \
RPM......29-38
Centrifugal Advance, Engine Degrees and RPM
Start Advance, atRPM
........................................................................\
................ 1000-1200
Medium Advance, Degrees at RPM..............................................................7.5-15 at 1400
Maximum Advance, Degrees at RPM
..........................................................28-32 at 3600
Vacuum Advance, Engine Degrees and In. of Vacuum Start Advance..
........................................................................\
.................-5at2.9-4.1 In.
Maximum Advance..........................................................................\
........1-5at4.5-5.0In.
Vacuum Retard, Engine Degrees at Closed Throttle............................................................-5
Condenser Capacity in
MicroFarads........................................................................\
.......23-.32
Breaker Spring Tension in Ounces........................................................................\
......14 to 19
Breaker Point Gap in Inches
........................................................................\
......................,016
Dwell AngleinEngine Degrees........................................................................\
.......... 50+3
Firing
Order........................................................................\
............................................l-3-4-2
Spark Plug or Coil Cable,Max.Resistance in Ohms
..................................................
10,000
Spark Plugs
Make and Model Production........................................................................\
............AC42FS
Make andModel
-Replacement........................................................................\
..........AC42FS
If carbon fouling occurs, use
........................................................................\
............AC43FS
Spark Plug Torque in
Lb.Ft.........................................................................\
.........................30
Spark Plug Gap in Inches........................................................................\
..........................,030
Valve Lifter Adjustment
One full turn (clockwise) after zero clearance is obtained - refer to Valve Adjustment
Procedure
Ignition Timing
Align timing marks with distributor retard hose disconnected and plugged\

RADIO - GT9c. 107mer screw and rotate screw until maximum volume
is achieved.
MAJOR REPAIR
REMOVING AND INSTALLING RADIORemoval
1.
Disc&ect battery.
2. Remove access trim plug from right side of con-
sole. See Figure
9C-1.Figure
9C-3 Location of Access Trim Cover3. Using a 8mm socket, remove hex head screw. See
Figure
9C-2.4. Remove access trim cover on left side of console.
See Figure
9C-3.5. Using a 4mm socket, remove
hex head screw. See
Figure
9C-4.6. Remove tear lock bolts by first,drilling a 3/16 inch
pilot hole and, using a
l/4 inch bolt extractor,
remove bolts. See Figure
9C-5.Figure
9C-5 Drilling Pilot HoleIn\, Tear Lock Bolts7. Disconnect ignition (white) and direction signal
(black) wire set plugs.
8. Support steering column assembly and remove
both hex head bolts.
9. Disconnect speedometer
cabI&10. Remove 6 instrument cluster retaining screws.
See Figure
9C-6.Figure SC-4 Location of Hex Head Screw and Flasher
UnitFigure SC-6 Removing Instrument Cluster Retaining
screws