1973 OPEL GT-R service

BATTERY AND CABLES - ALL MODELSlA- 7
421 Test
F$ocedure1. Visual Inspection
- The first step in testing the
Energizer br 12-V& Battery should be a visual in-
spection
which very often will save time, labor and
expense in determining the condition.
(a) Check for broken or cracked case or cover.
(b) Check ,for loose terminal posts.
fiozeck Ifor defective or mutilated sealing com-(d) Check for other visible signs of physical damage.
Obvious d?mage as a result of conditions described
above indicates the need for Energizer or batteryreplaceme$t.
2. The “421” Test is a programmed test procedure
consisting bf a series of timed discharge and charge
events, reqtdring approximately 2 to 3 minutes, that
will determine the condition of the Energizer or bat-
tery with a high degree of accuracy when used inconjunctioti with this entire test procedure. “421”
Testers
a$ produced by a number of different manu-
facturers
r+nd their directions for tester operation
should be carefully followed. General comments on
overall “42 1” Tester operation follow:
(a) Energi@rs or batteries should
nor be charged
prior to
making this test. Defects within the unit can
be hidden by the charging and erroneous test results
will be obtpined.
(b) Erratic, or extremely low, initial meter readings
may indicate poor connections at the tester termi-
nals.Obt{in clean and tight connections beforeper-
forming the 421
Test.(c) All meter readings should be made immediately
after the meter indicator light comes on even if the
meter needle is still moving.
(d) If additional discharges are required after the
initial discbarge, set meter indicator following thefast discharge cycle.
(e) Batteries designated as “bad” by the tester should
be replaced.
(f) Batteries designated as “good” with no owner’s
complaint or indication of poor performance, should
be left in s+vice. Posts, cable clamps, and top should
be cleaned, water should be added and recharging
should be
,performed, if required. For dependable
and reliable battery service, the battery should be in
at least a
75 per cent state-of-charge.
(g) Batteries designated as “good” that are suspected
of being questionable because of owner complaint, orage of the battery, should be further tested by the
Hydrometer Test.
HYDROMETER TEST OF BATTERY
The 421 Battery Test as described in the previous
paragraph is the fastest and most accurate means of
determining the serviceability of a one-piece cover
battery. However, ifa 421 Battery Tester is not avail-
able, a hydrometer test may be used on a battery that
has failed to give proper service.
Hydrometer Test1. Fully charge battery.
2. Measure specific gravity of each cell as described
in sub-paragraph below.
Decide battery serviceability as follows:
(a) If all cells read between 1.230 and 1.310, the
battery is okay. All it needed was a full charge.
(b) After fully charging battery, if any cell reads less
than 1.230, the battery is defective and should be
replaced.
Use of HydrometerThe Hydrometer measures the percentage of sulphu-
ric acid in the battery electrolyte in terms of specific
gravity. As a battery drops from a charged to a dis-
charged condition, the acid leaves the solution and
enters the plates, causing a decrease in specific
gravity of electrolyte. With a hydrometer, an indica-
tion of the concentration of the electrolyte is ob-
tained.
The specific gravity of the electrolyte varies not only
with the percentage of acid in the liquid, it also varies
with temperature. As temperature increases, the
electrolyte expands so that the specific gravity is re-
duced. As temperature drops, the electrolyte con-
tracts so that the specific gravity increases. Unless
these variations in specific gravity are taken into
account, the specific gravity obtained by the hy-
drometer may not give a true indication of the con-
centration of acid in the electrolyte.
Correction can be made for temperature by adding
,004, usually referred to as 4 “points of gravity”, to
the hydrometer reading for every 10 degrees F. that
the electrolyte is above 80 degrees F. or subtracting004 for every 10 degrees F. that electrolyte is below
80 degrees F. Figure IA-4 shows the exact correctionfigure to use for any temperature above or below 80
degrees F., the three steps used in obtaining the cor-
rected or true specific gravity, and two examples
showing how it is figured.

1A. 81873 OPEL SERVICE MANUALELECTROLYTESPECIFIC GRAVITY
TEMPERATURE
(F)CORRECTION
-+0&&n _
THERMOMETER 30”
EXAMPLE A:
--,012---,016---,026
- -.02h
- -.028
- -.032~
-.036
YEXAMPLE 6:TEMPERATURE = 120”
i.TEMPERATURE = -0” F.HYDROMETER = ,,230HYDRdiETER
= 1.230
READINGREADING
‘,9R2Ro~CF;‘“” = +.0,6go!RFfCilON = .,032
TRUE SPECIFIC = ,.246
GRAVITY;RU”v;,‘;CIFIC = 1.198
3xA‘l
Figure
l A-4 Specific Gravity Temperature CorrectionScale
When using a hydrometer, obsqve the following
pain Is:1. Hydrometer must be clean, inside and out, to in-
sure an accurate reading.
2. Hydrometer readings must never be taken im-
mediately after water has been added. The water
must be thoroughly mixed with the electrolyte by
charging for at least 30 minutes before hydrometer
values are reliable.
3. If hydrometer has built-in thermometer, draw liq
aid into it several times to insure correct temperature
before taking a reading.
4. Hold hydrometer vertically and draw in just
enough liquid from battery cell so that float is
freefloating, and with bulb fully released. Hold bydrom-eter at eye level so that float is vertical and free
!ofouter tube, then take reading at surface of liquid.
Disregard the curvation where the liquid rises
against float stem due to surface tension.5. Avoid dropping liquid on car or clothing as it is
extremely corrosive. Any liquid that drops should be
washed off immediately with soda solution.
FUSIBLE LINKSAll 1973 Opel Models have fusible links located be-
tween the starting motor post and the generator
regulator. These links are the weakest point in the
electrical supply system for the complete car, and, as
such, will act like a fuse for every wiring harness in
the
ca.r. Every electrical accessory is still protected
by a fuse or circuit breaker, of course, but fusible
links protect the wiring harnesses before the fuses.
A fusible link consists of soldering a smaller gauge
wire to a heavier gauge wire end to end. In the event
of a circuit overload where the heavier gauge
becomes short circuited, the fusible link or smaller
gauge wire will burn out first, thus, protecting its
circuit from major damage. These fusible links are
located in the engine compartment in such a manner
that if overheated, the possibility of a fire is veryr¬e.
The attachment of the fusible links and the circuits
they protect are as follows: See Figure
l A-5.
D+61TERMIN\AL ;;!$6,,FL #3
B+ TERMINAL
I3QlA5
SOLENOID ON STARTER
Figure
t A-5 Fusible LinksFusible link (1) is connected to the starter solenoid
at the battery cable terminal, on one end and to the
red and white stripped main feed wire at the other
end.
Fusible link (2) is connected between the red wirean&s
terminal of the voltage regulateand protectsagainst a situation where the battery will not accept
a charge and the generator is charging to handle
various electrical loads. Fusible link (3) is connected
between the light blue with white stripes wire and D

1 B- 101973 OPEL SERVICE #MANUAL
STARTlhG SYSTEM
/
ALL
MODEILS
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Starting SystemDescription
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . .
DIAGNOSIS:
Starting System Diagnosis,
. . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . \
. . . . . . . .
MAINTENANCE AND ADJUSTMENTS:Starting System
Checks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . .
MAJOR REPAIR:
Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . ., . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
CleaningandInspecting Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. .
Replacing Field Coils. . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . .
Checking and Replacing Brushes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing Bushings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . \
. . . . . . . . . . . . . . . . . . . . . .
Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . .
Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . .
SPECIFICATIONS:
Starter Specifications
. . . . , . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page No.
lB-10
16-10
18-12
18-13
18-13
18-14
18-14
16-15
18-16
lB-16
18-17
18-17
DESCRIPTION AND OPERATION
STARTING SYSTEM DESCRlPTlqN
The new Delco Remy starter for 1973 is a brush-
type series wound electric motor equipped with an
overrunning clutch and operated by a
soienoid. The
field frame is enclosed by the commutator end frame
and the drive housing and carries the pole shoes and
the
field coils. The armature has a spline on the drive
end which carries the over-running clutch and pinion
assembly. The armature shaft is supported in
sin-
tered bronze bushings in the commtitator end frame
and the drive end housing. These bushings are
packed with lubricant during initial assembly
and
TROUBLE DIAGNOSIS ’
STARTING SYSTEM DIAGNOSIS/
require no additional lubrication between overhaul
periods.
As the starter is operated by turning the ignition
switch on the instrument panel, the shift lever is
moved against spring tension. By means of the guide
ring, the shift lever moves the pinion into mesh with
the flywheel ring gear.
After the pinion meshes with the flywheel ring gear
teeth, the solenoid contact disc closes the circuit and
the engine is cranked. When the engine starts, the
speed of the rotating flywheel causes the pinion to
over-run the clutch and armature. The pinion con-
tinues to be engaged as long as the shift lever is kept
in the cranking position.
In case of cranking motor breakdown, it should be kept in mind that the
relevant cause(s) for the trouble may not only lie in the cranking mot\
or itself

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.

lB- 14 1973 OPEL SERVICE MANUAL !
6. Remove shift lever shaft and: lift armature aid
shift lever assembly.
7. Drive back retaining ring on armature shaft. See
Figure
lB-5.
8. Take the lock ring, retaining ring, and
over&-
ning clutch and pinion off armature shaft. Cheqk
groove in shaft for burrs and remove with a soft tile.
Cleaning and Inspecting Parts
1. Clean and check all parts. Replace defective parts.
2. Turn down worn or burnt
cominutator on a good
precision lathe. Use a spindle
speed between 2,000
and 3,000 RPM. See Figure
lB-6. When turning
down commutator, adjust cutting depth of tool
so
that no more pits exist after this:operation. Do not
remove any more material than necessary, however,
because if commutator diameter
is less than 1 15/32
inches, armature must be replaced.
30166
Figure 1B-6 Turning Down Commutator
3. Undercut mica approximately ,020 below com-
mutator surface. Finish and thoroughly clean
corn-
mutator.
I
4. Check armature for short circuit on a
growler.
5. With a test lamp, check armature for ground.
Test
lamp must not light up. See Figure
IB-7.
Figure 1B-7 Testing Armature for Grounds
j
6. Check armature for an open circuit on a growler.
Considerable variation in readings between in-
dividual commutator bars would indicate an open
circuit.
7. Visually check
field coils. Replace burnt or
scorched
field coils.
8. With a test lamp, check
field coils for ground. See
Figure
IB-8. Test lamp must not light up. Replzice
grounded field coil.
Figure lB-8 Checking Field Coils for Ground
Replacing Field Coils
1. Mark locations of pole shoes to avoid incorrect
installation.
Figure 1B-9 Removing Pole Shoes

lB- 16 1973 OPEL SERVICE MANUAL
8. Making sure that brush holder is aligned at right
angles to the
field frame, rivet brush holder to field
frame. See Figure
lB-14.
RIVET
Figure 18.14 Riveting Brush Holder to Frame i
Replacing Bushings
If sintered bronze bushings in. commutator ehd
frame and drive housing are worn, they must be
replaced. Soak new bushings in engine oil for at least
half an hour prior to installation. Press out old bush-
ings and press in new bushings. See Figure
lB-15.
Figure 18.15 Installing New Bushings
St& Assembly
1. Lubricate armature shaft. Install drive assembly
with pinion outward. 2. Slide pinion stop retainer down over shaft with
recessed side outward.
3. Place a new snap ring on drive end of shaft and
hold it in place with a hard
wood block. Strike block
with hammer to force snap ring over end of shaft,
then slide the ring down into groove in shaft. See
Figure
lB-16, view A.
7
(
I
I
E-.
Figure 1B-16 Pinion Stop Retainer and Snap Ring
Installation
4. Place thrust collar on shaft with shoulder next to
snap ring and move the retainer into contact with
ring. Using pliers on opposite sides of shaft, squeeze
retainer and thrust collar together until snap ring is
forced into the retainer. See Figure
lB-16, view B.
5. Lubricate drive housing bushing and install arma-
ture and drive assembly in housing.
6. Install solenoid thrust spring and solenoid.
Figure 1B-17 Applying Sealer to Starter

1 C- 18 1973 OPEL SERVICE MANUAL
IGNITIPN SYSTEM
CbNTENTS
Subject
DESCRIPTION AND OPERATION: Ignition System ..................................................................
Ignition
Switc,h....................................................................
Ignition Coil
..........................................................................\
Distributor
............................I...............................................
DIAGNOSIS: (Not Available)
MAINTENANCE AND ADJUSTMENTS: Contact PointReplacement ............................................
Dwell Angle Adjustment :
................................................
Ignition Timing Adjustment ..........................................
Ignition Wire Inspection :
..................................................
Check Ignition Output ......................................................
Check Distributor
..............................................................
Check Spark Plugs
............................................................
MAJOR REPAIR: Distributor Removal ..........................................................
Disassembly ........................
I...............................................
Reassembly
..........................I...............................................
Distributor Installation
....................................................
SPECIFICATIONS: /
Ignition
Coil ..........................................................................
Distributor
....‘........................i...............................................
Spark Plugs ........................................................................\
..
DESCRIPTION AND OPERATION
INGITION SYSTEM
The ignition system basically consists of an ignitipn
switch, ignition coil, distributor, battery and related
wiring. The ignition switch is located in the steering
column, the ignition coil is located left front inner fender
skirt and the distributor is located at the left
front of the engine.
IGNITION SWITCH
The combined ignition switch and steering lock ian
be switched to any one of the below listed positions.
Insert key with notch pointing upward.
Page No.
lC-18
lC-18
lC-19
lC-19
1 c-20
1 c-20
1 c-20
lC-21 r
lC-21
1 c-22
1 c-22
1 r-23
1 C-23
1 c-24
1 C-25
1 C-26
1 C-26
1 C-26
(Fully counterclockwise) Lock position. Ignition
locked, steering locked, only with key removed.
Electrical circuits disconnected except to main light-
ing switch and dome lamp. The
key can be removed.
0- (First position clockwise from lock) Garage posi-
tion. ‘The key and lock assembly must be pushed “in”
to reach this position from lock. The steering is un-
locked and the ignition is off. The electrical circuits
are the same as in lock position. The key cannot be withdrawn.
l- [Chposition.) All electrical circuits controlled by
ignition switch are completed through the switch.
The key cannot
be removed while switch is in drive
position.

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