1973 OPEL GT-R engine

HEATER SYSTEM - GT9A- 5
MAJOR REPAIR
REMOVAL AND INSTALLATION INSTRUMENT
PANEL FRESH AIR OUTLET
Removal
1. Remove instrument panel cover assembly. Refer
to Group 1.
2. Snap grille out of outlet.
3. Remove knob from lever and remove outlet.
Installation
1. Install outlet and knob onto lever.
2. Snap grille into outlet.
3.
Install instrument panel cover assembly. Refer to
Group 1.
REMOVAL AND INSTALLATION KICK PANEL
FRESH AIR OUTLET
Removal
Using a screwdriver, carefully pry out outlet.
Installation
Install outlet.
REMOVAL AND INSTALLATION BLOWER
SWITCH
Removal
i. Remove instrument panel assembly. Refer to
Group 1.
2. Unscrew switch assembly from panel.
Installation
1. Screw switch assembly to instrument panel.
2. Install instrument panel assembly. Refer to Group
1.
REMOVAL AND INSTALLATION HEATER
Ramova!
1. Remove lower radiator hose, drain, and collect
coolant. 2. Detach coolant feed (A) and return (B) hoses, in
engine compartment from heater core. See Figure
9A-5.
Figure 9A-5 Heater Hose Connections
3. In engine compartment remove hood lock control
cable retaining clip and cable from lock bar. See Figure
9A-6.
Figure 9A-6 Hood Release Control Cable
4. Remove console shift cover between seats using
the following instructions:
a. Remove ash tray and remove two screws under it.

9A-8 1973 OPEL SERVICE MANUAL
Installation
1. Install heater blower and case assembly, securing
with one (1) bolt at the top and two (2) nuts from the
bottom. See Figure
9A-15.
2. Install instrument panel padding and connect
heater and defroster duct hoses, making sure hoses
are properly positioned and connected. See Figure
9A-16.
Figure 9A-16 Heater and Defroster Duct Hoses
3. Install support bracket (B) and heater control (A).
See Figure
9A-12.
4. Carefully push cluster back into instrument panel
housing, making sure electrical wires, etc., are not
pinched.
5. Install six (6) cluster retaining screws. See Figure
9A-10.
6. Install directional signal flasher. See Figure
9A- 9.
7. Attach speedometer cable.
8. Attach two (2) multiple wire plug connectors in
steering column harness.
9. Install steering column. Refer to Group 90.
10. Install instrument panel cover and attach
through openings (points A and B). See Figures
9A-7
and 9A-8.
11. Install right and left opening covers. 12. Install the console shift
cover
between the seats
using the following instructions:
a. Install console cover over shift lever and rubber
shift lever boot.
b. Install cover by pushing down until cover snaps into the four (4) push button type studs.
c. Install two (2) screws under ash tray opening and
install ash tray. 13.
In engine compartment, install hood lock control
cable to lock bar using retaining clip. See Figure
9A-
6.
14. Attach return hoses (B) and coolant feed hoses
(A) to heater core. See Figure
9A-5.
15. Attach lower radiator hose and add collected
coolant.
16. Check for proper operation and leaks in system.
REMOVAL AND INSTALLATION DEFROSTER
OUTLET
Removal
1. Remove instrument panel cover assembly. Refer
to Group 1.
2. Remove screws securing outlet to cover assembly.
Installation1. Install defroster outlet, securing with screws.
2. Install instrument panel cover assembly. Refer to
Group 1.
Figure 9A-17 Heater Valve

HEATER SYSTEM. GT9A- 9
REMOVAL AND INSTALLATION HEATER VALVE
Removal
1. Remove lower radiator hose and drain and collect
coolant.
2. Disconnect control cable.
3. Loosen heater hose clamps and remove valve from
hoses. See Figure 9A-17.SPECIFICATIONS
EngineRecommended Coolant
.__,.__...._...__.,.,...,......Thermostat Opens At (Degrees) F.
..__..___...Installation
1. Install valve into heater hoses and install hose
clamps.
2. Connect control cable.
3. Install lower radiator hose and add collected coo-
lant.
.....................................Ethylene-Glycol Base
...................................................................189Cooling
SystemCapacity(WithHeater)..........................................................................6Qt.BlowerMotorType
......................................................................................................12VDC
BlowerFanType
..................................................................................................SquirrelCage

HEATER SYSTEM. OPEL 1900. MANTA9A- 11air is attained, as the water does not cool down in the
second part of the core.
A Water Outlet
B Water Inlet
The center lever actuates the two-stage blower mo-
tor.Lever positions:
Left to Center
- Motor Switched Off
Right of Center
- Lo Blower
Right
- Hi Blower
The lower lever opens and closes the air door which
channels the air flow to either the lower heater out-
lets or to the defroster outlets.
In the left lever position, the air inlet is closed. Up
to the center position, the air is directed
t,o the lower
heater outlets.
When moving the lever from center position towards
the right, the air flow to the lower
heatezr outlets is
reduced and increased to the defroster
csutlets.With the lever in its right position, the air is directed
to the defroster outlets only. For windshield defrost-
ing, all levers have to be moved to the right.
FUNCTION OF THE HEATER AND VENTILATION
SYSTEMThe engine hood is provided with slots in front of the
windshield. The air is directed through the slots into
the heater housing located in the engine compart-
ment, flows into the air distributor housing, and
from there to the lower heater outlets and,/or defros-
ter outlets, depending on the position of the control.
The two-stage blower motor is arranged in the heater
housing above the heater core and actuated by the
center control. The blower motor draws in the air
entering through the slots, blows the air through the
heater core into the air distributor housin:?, and from
there to the lower heater outlets and/or defroster
outlets, depending on the position of the lower con-
trol. See Figure 9A-32.
The heater valve regulates the flow of coolant
through the heater core, thereby varying
t:he temper-
ature of the air flow past the core.
The ventilation of vehicle interior is completed by a
draft-free air circulation pattern. Vent
slots are ar-
ranged below the back window which
are: connected
through channels to the rear quarter
iside panel.
From here, the inside air escapes into
the! open. TheFigure
9A-32 Air Flow
head wind (caused by the car traveling down the
road) promotes this process so that there is always
fresh air in vehicle interior.
On the Model 54 Station Wagon, there will be no air
outlets in the rear. For adequate flow-through type
ventilation, it will be necessary to open a rear win-
dow.Aside from the fresh air admission through the
heater system, two fresh air inlet nozzles are ar-
ranged in the center of the instrument panel. These
nozzles can be turned to direct the air flow in the
desired direction. In addition, rotary flaps allow the
regulation of the entering air or to shut off the air
completely.
These nozzles admit unheated fresh air only and
operate independent of the heater and defroster sys-
tem.
DIAGNOSIS
HEATER SYSTEM TROUBLE DIAGNOSIS
TROUBLETemperature of heated air at outlets too low.
CAUSE AND CORRECTIONCheck radiator cap for proper sealing action. Re-
place, if necessary.
Check for adequate coolant supply. If level is down,
correct cause of coolant loss and refill radiator.
Inspect hose for kinks. Relieve kink or replace hoses.
Check thermostat operation by measuring tempera-
ture of coolant at radiator. Temperature should be
within 5 degrees F. of thermostat rated value (189
degrees F.).

9A-14 1973 OPEL SERVICE MANUAL
upper attaching screw through opening for heater
control housing and lower attaching screw below
instrument panel. See Figure 9A.-38.5. On right side, viewed in driving direction, install
air distributor housing attaching screws. See Figure9A-37.
6. Install radio.
7. Install glove compartment.
8. Install bowden control wires to heater valve and
air distributor housing.
9. Install instrument cover.
10. Install heater switch lever.
Figure 9A-38 Upper Attaching Screw
9. Pull defroster outlets downwards and remove out-
lets through glove compartment opening. See Figure9A-39.
REMOVAL AND INSTALLATION OF HEATER
CONTROL HOUSING
Removal1. Remove instrument panel cover
- refer to operat-
ion,
IRemoving and Installing Instrument Housing.
2. Remove two sheet metal screws for control hous-
ing attachment. See Figure 9A-40.
Figure 9A-39 Removing Defroster Jets
Installation
1. Apply sealing compound between air distributor
housing and dash panel.
2. Install defroster outlets, securing with two (2)
clips at the instrument panel. See Figure 9A-39.
3. Install air distributor housing to dash panel,
4. On left side, viewed in driving direction, installFigure 9A-40 Control Housing Attaching Screws
3. In engine compartment, detach bowden control
wire from heater valve. See Figure 9A-41.
4. Detach bowden control wire from air distribution
flap. See Figure 9A-42.
5. Pull wires off blower switch. See Figure 9A- 43.

HEATER SYSTEM. OPEL 1900. MANTA9A- 15
Figure 9A-4 1 Bowden Wire Attachment
Figure SA-42 Control Wire
to Distribution? DoorAttachmentA
- Yellow Wire
B
- Grey Wire
C
- Brown Wire
6. Remove heater control housing.
Installation1. Install heater control housing,
2. Install wires onto blower switch. See Figure 9A-
53.Figure 9A-43 Blower Switch Wires
A
- Yellow Wire
B
- Grey Wire
C
- Brown Wire
3. Attach bowden control wire to air distribution
flap. See Figure 9A-42.
4. In engine compartment, attach bowden control
wire to heater valve. See Figure 9A-41.
5. Install two (2) sheet metal screws for control hous-
ing attachment. See Figure 9A-40.
6. Install instrument panel cover.
7. Adjust bowden control wires.
REMOVAL AND INSTALLATION OF HEATER
MOTOR
1. In engine compartment, remove five (5) shroud
cover attaching screws. See Figure 9A-44.
2. Carefully remove cover
3. Pull water hose off windshield wiper jet.
4. Disconnect wires to heater motor. For this pur-
pose, disconnect multiple plug connection on left
side of shroud. See Figure 9A-45.
5. Remove three (3) heater motor attaching screws.
See Figure 9A-46.
6. Take off motor.

9A-16 1973 OPEL SERVICE MANUAL
Figure 9A-44 Shroud Cover AttachmentsFigure 9A-46 Heater Motor Attaching Screws
Figure 9A-45 Heater Motor Wires
InstallationFigure 9A-47 Sealing Shroud
1. Install heater motor, attaching with three (3)
screws. See Figure 9A-46.
2. Connect multiple plug on left side of shroud. See
Figure 9A-45.3. Seal shroud cover front and rear contacting areas
with sealing cement. See Figure 9A-47.
4. Install shroud cover, attaching with five (5)
screws.SPECIFICATIONS
EngineRecommended Coolant
..........................................................................Ethylene-Glycol Base
ThermostatOpensAt(Degrees)
F.......................................................................................189Cooling System Capacity (With Heater)
..........................................................................6 Qt.
Blower Motor Type
......................................................................................................12 VDC
Blower Fan Type
..............................................................................................................Blade
Numberof FanBlades
..............................................................................................................7

REFRIGERANT COMPONENTS ALL MODELS99- 33
That the attraction of the drying material for mois-
ture is so powerful that if the receiver is left open,
moisture will be drawn in from the outside air.
That just one drop of water added to the refrigerantwill start chemical changes that can result in corro-
sion and eventual breakdown of the chemicals in the
system. Hydrochloric acid is the result of an R-12
mixture with water.
That the smallest amount of air in the refrigeration
system may start reactions that can cause malfunc-
tions.
That the drying agent in the receiver-dehydrator is
Activated Silica Alumina (silica-gel).
That
the inert gas in the expansion valve capillary
line is carbon dioxide.
DESCRIPTION OF AIR CONDITIONING
COMPONENTS
Compressor
The compressor is located in the engine compart-
ment. The purpose of the unit is to draw the low
pressure,gas from the evaporator and compress this
gas into a high temperature, high pressure gas. This
action will result in the refrigerant having a higher
temperature than the surrounding air.
The
cortipressor is of basic double action piston de-
sign. Three horizontal double acting pistons make up
a six cylinder compressor (See Figure
9B-162). The
pistons operate in
l-1/2 inch bore and have a l-1/8
inch stroke. A
wash plate keyed to the shaft drives
the pistons. The shaft is belt driven through a mag-
netic clutch and pulley arrangement. An oil pump
mounted at the rear of the compressor picks up oil
from the
botto’m of the compressor and lubricates the
bearings’and other internal parts of the compressor.
Reed type valves at each end of the compressor open
or close to control the flow of incoming and outgoing refrigerant. Two gas tight passages interconnect
chambers of the front and rear heads so that there is
one common suction port, and one common dis-
charge port. The internal parts of the compressor
function, as follows:
1. Suction Valve Reed Discs and Discharge Valve
Plates
_ The two suction valve reed discs and two
discharge valve plates (see Figure
9B-25) operate in
a similar but opposite manner. The discs are com-
posed of three reeds and function to open when the
pistons are on the intake portion of their stroke
(downstroke), and close on the compression stroke.
The reeds allow low pressure gas to enter the cylin- ders. The discharge valve plates also have three
reeds, however, they function to open when the pis- tons are on the compression portion of their stroke
(upstroke), and close on the intake stroke. High pres-
sure gas exits from discharge ports in the discharge
valve plate. Three retainers riveted directly above the
reeds on the valve plate serve to limit the opening of
the reeds on the compression stroke.
SUCTION VALVE
DISCHARGE-VALVE PLATES
Figure
98-25 - Compressor Suction Valve Reed Discs
and Discharge Valve Plates
2. Front and Rear Heads - The front and rear heads
(Figure
9B-26) serve to channel the refrigerant into
and out of the cylinders. The front head is divided
into two separate passages and the rear head is di-
vided into three separate passages. The outer passage
on both the front and rear heads channels high pres-
sure gas from the discharge valve reeds. The middle
passage of the rear head also contains the port open-
ing to the superheat switch cavity. This opening in
the rear head permits the superheat switch to be
affected by suction gas pressure and suction gas tem-
perature for the operating protection of the compres-
sor. The inner passage on the rear head houses the
oil pump inner and outer rotors. A Teflon sealing
material is bonded to the sealing surfaces separating
the passages in the rear head.
“0” rings are used to
affect a seal between the mating surfaces of the heads
and the shell. The front head suction and discharge
passages are connected to the suction and discharge
passages of the rear head by a discharge tube and
suction passage in the
body of the cylinder assembly.
A screen located in the suction port of the rear head
prevents foreign material from entering the circuit.
3. Oil Pump
- An internal tooth outer rotor and
external tooth inner rotor comprise the oil pump.
The pump works on the principle of a rotary type pump. Oil is drawn up from oil reservoir in underside
of shell through the oil inlet tube (see Figure
9B-27)