ECU OPEL GT-R 1973 Manual PDF

98-62 1973 OPEL SERVICE MANUAL
Figure 98.99 Refrigerant Hoses Retainer Grommet
-Under Car - GT
8. From under car install four (4) nuts securing
evaporator mounting bracket to floor. See Figures9B- 92 and
9B-93.Figure 98.100 Refrigerant Hoses
- Under Car GT
9. Evacuate system. Refer to EVACUATING SYS-
TEM.
10. While system is being evacuated, connect drain
hoses underneath evaporator housing.
11. Plug in the resistor assembly electrical connector
plug and connect the blower motor connection and
install ground wire and 2 mounting brackets to case
screws using the rearward holes. See Figure
9B-90.12. Install the evaporator cover and all cover screws.
See Figure
9B-88.13. Install luggage tray and attaching screws. See
Figure
9B-87.14. Connect the negative battery cable.
15. Charge system. Refer to CHARGING SYS-
TEM.
REMOVAL AND INSTALLATION OF CONDENSERRECIWER- DEHYDRATOR ASSEMBLY
- GT
Removal
1. Disconnect negative battery cable.
2. Discharge system. Refer to DISCHARGING
SYSTEM.
3. While the system is discharging, remove the
charcoal cannister, washer jar, battery and battery
tray. Battery needs only to be set up out of the way
and not removed from the car.
4. Disconnect inlet and outlet pipes of condenser
receiver-dehydrator and tape closed the open ends of
refrigerant lines, and also the open ends of the inlet
and outlet pipes of the condenser. See Figure 9B-101.
5. Disconnect discharge line from condenser and
tape closed open ends of discharge pipe and con-
denser inlet.
6. Remove 4 condenser attaching screws and lift out
condenser. See Figure 9B-101.
7. Remove 2 screws retaining receiver-dehydrator
to condenser and remove.
Figure
9B-101 Receiver - Dehydrator. Condenser
Attaching Screws and Brackets
- GT
Installation
If refrigerant circuit or condenser has been exposed
to the atmosphere and moisture may be present in
the circuit, the system and/or component must be
flushed prior to installation. Refer to FLUSHING
THE SYSTEM.
1. Install receiver-dehydrator to condenser and fas-
ten with 2 clamps and 2 screws.

REFRIGERANT COMPONENTS ALL MODELSSB-632. Install condenser into car and secure with 4 at-
taching screws. See Figure
9B-101.3. Untape discharge line and pipe and install using
new o-rings lubricated with No. 525 viscosity oil.
Figure
99.102 Condenser - Receiver - Dehydrator
O-Rings. GT
4. Untape and install inlet and outlet pipes into the
receiver-dehydrator using new o-rings lubricated
with No. 525 viscosity oil.
Figure
98-103 Condenser Assembly - GT
5. Evacuate system. Refer to EVACUATING SYS-
TEM.
6. While system is being evacuated, install the char-
coal cannistor, washer jar, battery tray and battery
and connect negative battery cable.
7. Charge system. Refer to CHARGING SYS-
TEM.
DISASSEMBLY AND REASSEMBLY OF CLUTCH
DRIVE PLATE AND SHAFT SEALIt is not necessary to remove the compressor or dis-connect refrigerant lines to remove or install clutch
parts on the GT, however, the compressor must be
removed from the Opel 1900
- Manta.
Disassembly
1. Firmly clamp holding fixture (J-9396) in a vise
and attach compressor assembly to fixture (see Figwe
9B-104).
-_ .s -Figure SE-104 Removing or Installing Shaft Nut
2. Hold hub of clutch drive plate with wrench
(J-9403). Using special thin wall 9/16 inch socket
(J-9399) and 3/g inch drive, remove shaft nut.
3. Install threaded hub puller (J-9401) onto hub of
clutch drive plate (see Figure
9B-105). Hold body of
hub puller with wrench, tighten center screw of hub
puller, and lift off clutch drive plate and woodruff
key.Figure SE-105 Removing Clutch Drive Plate

9B-66 1973 OPEL SERVICE MANUAL
LEAK TEST
FIXTURE
\ Js - s ---Y623
\COMPRESSOR
ADAPTERS
J-5420
USE LINE ONLY
DURING
-
COMPRESSOR
SEAL TEST
-4
-
It-’rDISCHARGE LINE
-
LOW PRESSUREHIGt
GAGE
4
PRESSURE
GAGE
(TOP VIEW)
GAGE
*-LINE (3)
J-54 18
GAGE SET
REFRIGERANT
J-5725-01
-CYLINDER
LMANIFOLD AND
9&86
Figure 9B-112 Leak Testing Shaft Seal and Seal Seat O-Ring
the sleeve retainer is recessed approximately l/32”
from the face of the compressor neck. 11. Reassembly spacer into hub ofclutch
drive plate.
9. Insert woodruff key into hub of clutch drive plate
so that it projects out approximately
3/16 inch (see
Figure
9B-113) and position clutch drive plate onto
shaft.
10. Using drive plate installer (J-9480), screw in-
staller on end of shaft as shown in Figure
9B-114.
Hold nut and turn bolt until clutch drive plate is
pressed within
3/32 inch of the pulley assembly.
12. Reassemble retainer ring into hub of clutch drive
plate (see Figure
9B-106) using No. 21 truarc pliers
(J-5403).
13. Thread on new shaft nut using special thin wall
9/16 inch socket (J-9399) and 3/8 inch drive. Hold
clut~ch drive plate secure using Wrench (J-9403) and
torque nut to 15 lb. ft. The air gap between the
friction surfaces of the pulley assembly and clutch

98-92 1973 OPEL SERVICE MANUAL
MAJOR REPAIR
REMOVAL AND INSTALLATION OF BLOWER
SWITCH
Removal
I. Remove the face plate retaining screws and
remove the face plate assembly. See Figure 9B-172.
Figure SE-172 Face Plate Retaining Screws andcontrots
2. Remove the blower switch retaining screws and
remove switch.
Installation
1. Install the blower switch and retainer screws.
2. Install the face plate and secure with the retainer
screws. See Figure
9B-372.
REMOVAL AND INSTALLATION OF
TEMPERATURE CONTROL SWITCH
Removal
1. Remove the face plate retaining screws and
remove the face plate assembly noting the position of
the air sensing capillary so that it can be reinstalled
in the same location as when removed. See Figure
9B- 173.
2. Remove the temperature control switch retaining
screws and remove switch.
AIR SENSING CAPILLARY,yT,,ERMOSTATIC SWITCH
!IBUMPERBLOWER SWITCH98-136
Figure SB-173 Location of Air Sensing Capillary
Installation
1. Install the temperature control switch and secure
with the retaining screws.
2. Position the air sensing capillary in the exact
location as was noted when removing.
3. Install the face plate and secure with the retain-
ing screws. See Figure
9B-172.
REMOVAL AND INSTALLATION OF RESISTOR
ASSEMBLY
Removal
1. Disconnect the negative battery cable.
2. Remove the glove box assembly. 3. Disconnect the electrical plug from the resistor
assembly. See Figure
9B-176.
4. Remove two (2) screws and remove resistor as-
sembly.
Installation
1. Install the resistor assembly and secure with two
(2) screws.
2. Install the electrical plug onto the resistor assem-
bly. See Figure
9B-176.
3. Install the glove box assembly.
4. Connect the negative battery cable.
REMOVAL AND INSTALLATION OF BLOWER
MOTOR ASSEMBLY
REMOVAL
1. Remove the negative battery cable from the bat-
tery.

5. If the low side pressure was less than the pre-
scribed pressure at the end of each cooling cycle, turnthe adjusting screw a partial turn clockwise. See Fig-ure 9B-192.AIR CONDITIONER SYSTEM
- GT9B- 99
CONNECTOR
Figure 98.192 Adjusting Thermostatic Switch6. If the pressure was more than the prescribed
value, tuin the adjusting screw counter-clockwise.7. Reinstall switch end plate and install switch in
face plate. Install face plate on evaporator assembly
assuring
,that the air sensing capillary has been re-
placed properly.
Figure 98-l 93 Vacuum Switch8. Check system performance. Iffurther adjustment
is needed, repeat steps 3 thru 7 until the correct
pressure is reached.
REMOVAL AND INSTALLATION OF BLOWER
SWITCHDo not attempt to run a performance test with the
duct assembly and switch removed from the
evaporator assembly
- inaccurate readings will re-
sult. Always replace the switch and duct assemblies
before c+ecking the system performance.
Removal
MAJOFi REPAIR
1. Remove the negative cable from the battery2. Remove the retaining screws from the duct as-
sembly. See Figure
9B-190.3. Remove 2 blower switch rejaining screws and
remove blower switch.
REMOVAL AND INSTALLATION OF VACUUM
SWITCH,
Installation
Ramoval~1. Remove right trim pad below instrument panel.
2. Rembve two (2) screws and unplug the vacuum
hose and electrical connector. See Figure
9B-193.1. Install the blower switch and
secure with two (2)
retaining screws.
2. Install the duct assembly retaining screws.
3. Install the negative battery cable.
Installation1. Install two (2) screws and plug in electrical con-
nector and connect the delay restrictor and checkvalve
hose assembly.
I
REMOVAL AND INSTALLATIDN:OF
TEMPERATURE CONTROL SWITCH
Removal2. Install right trim pad.I. Remove the negative battery cable.

gB-100 1973 OPEL SERVICE MANUAL
2. Remove the retaining screws from the duct as-
sembly. See Figure 9B-190.3. Lift up duct assembly and note the position of the
air sensing capillary so that it can be reinstalled in
the same location as when removed.
4. Remove the temperature control switch retaining
screws and remove switch.
Installation
1. Install the temperature control switch and secure
with the retainer screws.
2. Position the air sensing capillary in the exact
location as was noted when removing.
3. Install the duct assembly retaining screws.
4. Install the negative battery cable.
REMOVAL AND INSTALLATION OF RESISTOR
ASSEMBLY
Removal1. Remove the negative battery cable from the bat-
tery.2. Remove the luggage tray attaching screws and
lift out tray. See Figure 9B-194.
Figure 98-194 Luggage Tray3. Remove all evaporator cover attaching screws
and remove cover. See Figure
9B’-195.Figure 98.195 Evaporator Cover Assembly and
Attaching Screws
4. Remove the electrical plug connector from the
resistor assembly.
5. Remove 2 resistor attaching screws and remove
resistor assembly. See Figure 9B-197.
/98-147Figure 9B-196 Resistor and Blower Motor
Connections

98-102 1973 OPEL SERVICE MANUAL
2. Discharge system. Refer to DISCHARGING
SYSTEM in Refrigerant Components Section.
3. While system is discharging remove the luggage
tray attaching screws and lift out tray. See Figure9B-200.
4. Remove all evaporator cover screws and remove
cover. See Figure
9B-201.Figure
98.202 Evaporator Cover and Luggage Tray5. Remove the electrical plug connector from the
resistor assembly, and unplug blower motor connec-
tion and remove ground wire. See Figure
9B-203.6. From underneath evaporator housing, discon-
nect 2 drain hoses. See Figure 9B-204.
EVAPORATORFigure
98.204 Drain Hose
7. From under car remove 4 nuts securing evapora-
tor mounting bracket to floor. See Figure 9B- 205
and 9B-206.
Figure
98.203 Electrical Connections and Ground
WireFigure 98-205 Evaporator Mounting Bracket Bolts -Driver Side

98-104 1973 OPEL SERVICE MANUAL
the el&trical connector side of the motor to the right
side of the bracket.
2. Assemble the fan housing case halves and attach
the cover plate.
3. Install the resistor assembly.
4. Install the evaporator assembly into the car and
install mounting bracket. See Figure
9B-209.5. Untape the refrigerant lines and the inlet and
outlet pipes from the evaporator and install using
new o-rings on line fittings.
6. From under the car, install 4 nuts securing
evaporator mounting bracket to floor. See Figures9B- 205 and
9B-206.7. Evacuate system. Refer to EVACUATING SYS-
TEM in REFRIGERANT COMPONENTS Sec-
tion.
SPECIFICATIONS8. While system is being evacuated:
9. Connect 2 drain hoses underneath the evaporator
housing.
10. Plug in the resistor assembly electrical connector
plug and connect the blower motor connection and
install ground wire and 2 mounting bracket to case
screws using the rearward holes.
S’ee Figure 9B-209.11. Install the evaporator cover and all cover screws.
See Figure 9B-202.
12. Install luggage tray and attaching screws. See
Figure
9B-202.13. Connect the negative battery cable.
14. Charge system. Refer to CHARGING SYSTEM
in Refrigerant Components Section.

RADIO. GT9c- 105
RADIO
GTCONTENTS
Subject
DESCRIPTION AND OPERATION: (Not Applicable)
DIAGNOSIS:
RadioTroubleDiagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAINTENANCE AND ADJUSTMENTS:
Antenna Trimmer Adjustment
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAJOR REPAIR:
RemovingandInstallingRadio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .SPECIFICATIONS: (Not Applicable)
Page No.
9c-105
9C-106
9c-107
DIAGNOSIS
RADIO TROUBLE DIAGNOSISBecause radio problems are most often repaired at
United Delco authorized warranty repair stations,
the tendency for many dealer servicemen is to
remove the set when a problem is reported, without
any preliminary diagnosis. This results in a large
number of radios showing up as “NO TROUBLE
FOUND” units when received by the warranty re-
pair stations. This indicates that the trouble can
often be corrected without removal of the radio.
The inconvenience to an owner of driving without a
radio while his set is being serviced at a warranty
station can frequently be avoided if the following
quick checks are used to eliminate external radio
system :problems before removing the radio for re-
pair.
Always determine from the owner the exact nature
of the radio problem as an aid to diagnosis. Knowing
whether the condition is intermittent or constant,
whether it occurs with engine off or running, with
car stationary or moving, will help to pinpoint the
problem. Never turn on radio with speaker discon-
nected.
Radio Ii
Inoperative.1. Turn on the radio. The dial should light and a
thump should be heard from the speaker.a. If a thump is heard, go to Step No. 2 for antenna
check.b. If no thump is heard,
check the fuse.
(1) If fuse is bad, replace and try radio again. Race
engine and, if fuse blows again,‘remove the radio and
speaker assembly for repair by
4 trained radio techni-
cian.
(2) If fuse is good, check to
s&e that the speaker-to-
receiver interconnecting cable is connected securely.
If there is still no thump when the radio is turned on,
remove the receiver and speaker for repair.
2. Check the antenna by substituting with one held
out the car window.
a. If radio is still dead with substitute antenna,
remove the receiver and spea!er for repair.
b. If radio operates near normal with substitute an-
tenna, some part of the car antenna or lead-in is at
fault.
Radio Reception Is Weak1. Check to see if antenna trimmer is peaked.
a. Position antenna at a height of 31 inches.
b. Tune radio to weak station at or near 1400 KHz
on the dial, and turn volume control to maximum.

9C-106 1973 OPEL SERVICE MANUAL
c. Adjust trimmer screw for maximum volume.
d. If antenna trimmer does not have a definite peak, check for defective antenna by substitution.
2. Check that the speaker connection is plugged in
SXUdY.
3. If the radio is still weak, remove the receiver and
speaker assembly for repair.
Radio Is Noisy
1. Radio is noisy all the time:
a. Check for defective antenna by striking antenna
with hand. If static is heard while tapping, replace
antenna.
b. If antenna is not defective, remove receiver and
speaker for repair.
2. Radio is noisy only when jarred:
a. Check antenna as in Step No. 1 above.
b. Check speaker connection. If speaker connection is not at fault, remove receiver and speaker for re-
pair.
3. Radio is noisy when engine is running:
a. Check noise suppressor by substituting on genera-
tor with known good one.
b. Check to see that antenna is mounted securely,
grounding the antenna base to the fender. The an-
tenna lead-in wire is shielded and the shield should
have good ground connection at the receiver and the
antenna base.
c. Check for other car wiring, passing too close to
radio receiver case.
d. If engine noise is still present, remove receiver and
speaker for repair.
4. Radio is noisy when car equipment is operated,
such as directional lights or brake lights:
Check for defective antenna lead-in wire or, loose
antenna mounting, as in Step No. 3b above.
MAINTENANCE AND ADJUSTMENTS
ANTENNA TRIMMER ADJUSTMENT
An antenna trimmer adjusment screw is provided for
matching of the antenna coil in the receiver to the car antenna. This adjustment must always be made after
installation of a receiver or an antenna, or after re-
pair to these units. This adjustment should also be
performed whenever radio reception is unsatisfac-
tory.
1. Position antenna to a height of 31 inches.
2. Tune receiver
tb a weak station at or near 1400
KHz that can barely be heard
with volume turned
fully up.
3. Insert a small-bladed screwdriver in antenna trim-
Figure 9C-1 Location of Access Trim Plug
Figure
9C-2 Removing Hex Head Screw