1973 OPEL GT-R heater

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

SA-10 1973 OPEL SERVICE MANUAL
HEATER SYSTEM
OPEL 1900 - MANTA
CONTENTS
Subject
DESCRIPTION AND OPERATION:
Heater System
. . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Function of the Heater
and Ventilation System
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .DIAGNOSIS:
HeaterSystem
Trouble
Diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAINTENANCE AND ADJUSTMENTS:
ControlCable
Adjustment
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .MAJOR REPAIR:
Removal&InstallationHeaterHousing,. . . . . . . . . . . . . . . . . . . .Removal
& Installation Defroster Jets. . . . . . . . . . . . . . . . . . . . . .Removal
81 Installation Heater Control Housing . . . .
Removal
& Installation Heater Motor. . . . . . . . . . . . . . . . . . . . . . . .SPECIFICATIONS:
Specifications
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page No.
9A-10
9A-11
9A-11
PA-12
PA-12
9A-13
9A-14
9A-15
9A-16
DESCRIPTION AND OPERATIONHEATER SYSTEM
The temperature of the air entering the vehicle is
regulated by the heater valve and the blower. The
distribution of this air is controlled by the heater air
distributor housing under the instrument panel.
Moving the upper control lever from the left towards
the right opens the heater valve. This lever regulates
the flow of coolant through the heater core and
thereby increases or decreases the air temperature
proportionate to its travel. See Figure 9A-30.
Figure 9A-30 Heater Control AssemblyThe connectors for water inlet and outlet are located
on the left side of the heater core, viewed in driving
direction. The coolant flow is shown in the drawing.
See Figure 9A-3 1.
Figure
9A-31 Coolant Flow in Heater Core
Due to the separation of the inflowing and outflow-
ing water in the heater core, an even heating of the

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-i2 1973 OPEL SERVICE MANUAL
Check that air doors and water temperature control
valve are operating properly.
Check for plugged heater core-backflush heater core
as necessary.TROUBLEInadequate defrosting action.
CAUSE AND CORRECTIONExamine heater-defroster door for proper operation.
Adjust bowden cable so that door is fully closed in
FULL DEFROST position.
Check that air hoses connecting to defroster outlets
are secure.
Check for air leaks around edges of heater air dis-
tributor housing. Seal leaks, as necessary, with bodysea@. Check for body air leaks and seal, as neces-
sary, with body sealer.
TROUBLEBlower inoperative.
CAUSE AND CORRECTIONCheck blower fuse. Replace, if necessary, fuse posi-
tion 4
- amperage 15.
Check wiring for open circuit. Correct, as required.
Inspect for defective component, (i.e., blower switch
or blower motor)
- replace or repair as necessary.
MAINTENANCE AND ADJUSTMENTS
CONTROL CABLE ADJUSTMENTAdjustment of control cables is accomplished by po-
sitioning of the jacket or sheath of the control cable,
as held by the clamps on the control assembly and
heater case or by loosening screws and slidingbowden wire to obtain desired door or water valve
position.
MAJOR REPAIR
REMOVING AND INSTALLING HEATER HOUSING
Removal1. Unscrew hood lock together with ground wire(ground wire only on vehicles with radio interference
suppression). See Figure 9A-33.
Figure 9A-33 Hood Lock Attachments
2. Unscrew heater housing cover.
3. Pull hose of windshield washer system off jet and
take jet out of housing cover.
4. Unscrew bowden control wire from heater valve.
5. Unscrew heater housing from dash panel and pull
it off carefully. See Figure 9A-34.
Figure 9A-34 Heater Housing Attachments
6. Remove water hoses from heater core and pull
heater core out of heater housing. See Figure
9A-35.

Figure SA-35 Heater Core
Installation
1. Apply sealing compound between heater housing
and dash panel.
2. Install heater core into heater housing and attach
water hoses. See Figure 9A-35.
3. Instaii heater housing to dash panel. S,ee Figure9A-44.
4. Install bowden control wire to heater valve.
5. Install windshield washer jet into housing cover
and attach hose.
6. Install heater housing cover, and seal with a seal-
ing compound.
7. Install hood lock, together with
grc’und wire
(ground wire only on vehicles with radio interference
suppression).
REMOVING AND INSTALLING
DEFROSTE+lOUTLETS
Removal
1. Pull out heater switch lever. See Figure 9A- 36.
2. Remove instrument cover.
3. Unscrew bowden control wires from heater valve
and air distributor housing and pull out heater con-
trols.
4. Remove glove compartment.
HEiATER SYSTEM - OPEL 1900 - MANTA9A. 13Figure SA-36 Removing Heater Switch Lever
5. Remove radio.
6. On right side, viewed in driving direction, remove
air distributor housing attaching screws. See Figure9A-37
Figure SA-37 Air Distributor Housing Attaching
SCWWS7. On left side, viewed in driving direction, remove
upper attaching screw through opening for heater
control housing and lower attaching screw below
instrument panel. See Figure 9A-38.
8. Pull air distributor housing off dash panel

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