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HEATER AND AIR CONDITIONING 1A-4
CHEVROLET SHOWN AS
TYPICAL OF CHEVROLET
AND CHEVELLE
CHEVROLET
WITH CONSOLE
ONLY
THESE USED ON
CHEVROLET ONLY
Fig. 5— Heater Blower and
Air
Inlet (Chevrolet, Chevelle, Camaro)
Core
Replacement
1.
Drain radiator.
2.
Remove the heater hoses at their connections beside
the air inlet assembly.
NOTE:
The hose from the
water,
pump
must go
to the top heater core pipe; the other hose runs
from the thermostat housing to the lower core
pipe. (See Figure 8)
3.
Remove the bowden cables (except the Chevrolet
defroster cable) and all electrical connectors from
the heater and defroster assembly.
4.
On the engine side of the dash, remove the nuts from
the core case studs coming through from the inside
of the car.
5. Inside the vehicle, remove the case to firewall
mounting screws and pull the entire heater and de-
froster assembly from the firewall (remove the
Chevrolet defroster cable at this time) then remove
the assembly from the vehicle and set on a bench.
6. Remove the core assembly retaining springs and
remove the core.
7. Install the replacement core.
NOTE:
Be sure the core to case sealer is
intact before replacing core. Replace with new
sealer if necessary.
8. Replace the core and core retaining springs.
9. Within the vehicle (after attaching the Chevrolet
defroster cable) insert the five studs on the heater
and defroster assembly through the holes in the
cowl and blower and air inlet assembly. Replace the
case to firewall mounting screws and (on the engine
side) the five stud nuts.
10.
Replace the remaining bowden cables and electrical
connectors.
11.
Replace heater hoses, being careful to reinstall
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HEATER AND AIR CONDITIONING 1A-5
them in their proper location. (See Figure 8)
12.
Refill radiator.
Defroster Duct
Figure 9 illustrates the defroster duct installation
on Chevrolet, Chevelle and Camaro vehicles.
Bowden Cobles
Bowden cable attachment should be made in the fol-
lowing manner:
1.
With the cables attached to the control assembly
and levers, move the levers to their fully left or
closed position.
2.
Attach cable wires to the heater valve levers and
tighten cable attaching bracket screws.
3.
Check for proper cable operation and readjust as
necessary.
Control Panel
Control panel installation is shown in Figures 10, 11,
and 12.
Fan Switch
Replacement
1.
Remove control assembly-to-instrument panel re-
inforcement attaching screws and push the control
assembly toward the front of the vehicle and down.
2.
Remove the two switch attaching screws and the
electrical connector.
3.
Replace switch, screws, and electrical connector.
4.
Place control assembly into instrument panel and
replace attaching screws.
Resistor
The resistor assembly is attached to the heater dis-
tributor assembly. It should "be replaced if low or
medium blower speed is inoperative. Remove the glove
box for access to the unit.
HEATER HOUSING
LOWER RIGHT HAND
RETAINER NUT
Fig.
6—Air Distributor Duct (Camaro)
Fig.
7—Access to Blower and Housing (Chevelle)
CHEVY II
Heater Assembly
Removal (Fig. 13)
1.
Drain radiator.
2.
From within engine compartment;
a. Remove heater hoses from heater inlet and outlet
connections.
b.
Remove three nuts around blower motor attaching
heater assembly to dash panel.
3.
From within vehicle:
a. Remove glove box and glove box door.
b.
Remove screw attaching distributor bracket to
dash.
c. Remove the screw attaching case bracket to the
adapter assembly bracket.
d. Carefully detach heater assembly from dash panel
and adapter assembly and lower it toward floor of
vehicle.
e. Disconnect all bowden cable connections, the
wiring connector and the defroster hoses.
4.
Remove the heater assembly from the vehicle.
Core Replacement
1.
'With the heater assembly removed from the vehicle,
remove the screws attaching the core cover to the
heater assembly.
2.
Remove the core mounting screws and remove the
core from the assembly.
3.
Replace with a new core and replace the core cover.
Installation
1.
Be sure the adapter seal and blower motor seal are
in place and set into place beneath the instrument
panel.
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HEATER AND AIR CONDITIONING 1A-6
CHEVROLET SHOWN AS TYPICAL
Fig.
8—Heater Hose Routing (Chevrolet Shown as Typical)
cables, defroster hoses and the
place and install all at-
4.
5.
6.
Attach all bowden
wiring connector.
Set heater assembly into
taching nuts and screws.
Attach inlet and outlet hoses.
Replace glove box and glove box door.
Refill cooling system.
Defroster Duct
Installation of the defroster duct as used in Chevy H
vehicles is illustrated in Figure 14.
Blower Motor
Replacement
1.
Remove the heater assembly from the firewall.
Remove the five screws attaching the motor and
blower to the heater assembly.
2.
Remove the retainer attaching blower to the motor
shaft.
3.
Replace blower on new motor assembly, balance and
reinstall into heater assembly.
Fan Control
Replacement
1.
Remove the screws at the dash lower edge which
retain the control assembly and lower the assembly.
2.
Disconnect the blower harness connector and remove
the switch retaining screws and switch.
3.
Install the replacement switch with the nylon bearing
inserted into the AIR - FAN lever slot.
4.
Connect the blower harness connector and remount
the control assembly in the dash.
CORVETTE
Blower Assembly
Removal
1.
Remove the radiator supply tank from its retaining
straps and move it out of the way, then disconnect
the battery positive cable.
NOTE:
It is not necessary to drain the radiator.
2.
Remove the connectors from the blower motor.
3.
Scribe or chalk a mark on the blower motor mount-
ing plate and blower assembly.
4.
Remove the five screws retaining the blower mount-
ing plate to the blower inlet assembly.
Withdraw the blower assembly from the inlet
5.
assembly.
Disassembly
Remove the blower wheel from the motor by removing
the nut and tapping the motor shaft with a soft hammer.
Installation
1.
Assemble the blower to motor and using the scribe
mark, properly position the blower assembly on the
inlet assembly and install the five screws.
2.
Replace the electrical connectors on the blower
motor.
3.
Replace the radiator supply tank and the battery
positive cable.
Blower and Air Inlet Assembly
Removal
1.
Drain the radiator.
2.
Remove the radiator supply tank from its retaining
straps and swing it out of the way.
3.
Remove the battery.
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HEATER AND AIR CONDITIONING 1A-7
Fig.
10—Control Assembly (Chevrolet)
6. Remove the seven stud nuts attaching the blower
and air inlet assembly to the dash panel.
7.
Remove the blower and air inlet assembly from
beneath the fender.
8. The blower assembly may be removed and dis-
assembled as described under "Blower Assembly"
above.
Installation
1.
With the blower and air inlet assembly in place,
install the seven attaching stud nuts.
2.
Replace the blower motor electrical connectors.
Fig.
9—Defroster Duct (Chevrolet, Chevell^, Camaro)
4.
Disconnect the blower motor electrical connectors.
5.
Remove the water hoses from the heater core inlet
and outlet connections.
\
N
^
1
Fig.
11-Controi Assembly (Chevelle)
CHEVROLET CHASSIS SERVICE MANUAL
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HEATER AND AIR CONDITIONING 1A-8
Fig.
12—Control Assembly (Camaro)
3.
Replace the battery and radiator supply tank.
4.
Replace each heater hose to its proper core
connection.
5. Refill the radiator.
Defroster Duct
Figure 19 illustrates the installation of the Corvette
defroster duct.
Fig.
13—Chevy II Heater Components Removal
Fig.
U-Defroster Duct (Chevy 11)
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HEATER AND AIR CONDITIONING 1A-9
Fig.
15-Heater Control Assembly and Cables (Chevy II)
Resistor Removal
Two screws attach the resistor to the rear side of
the heater assembly.
Heater Assembly
Removal
1.
Drain the radiator.
2.
Remove the radiator supply tank from its support
Fig.
16—Heater Hose Routing (Chevy II)
straps and move it out of the way.
3.
Remove the battery.
4.
Remove the water supply hoses from the core
connections.
5. Remove the blower and air inlet assembly as de-
scribed above.
6. Remove the glove compartment and the panel on
either side of the instrument panel console as out-
lined in the Body Section of this manual.
Fig.
17—Corvette Heater and Blower Inlet Assembly
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HEATER AND AIR CONDITIONING 1A-10
PLATE RETAINERS
CORE BRACKET SCREWS
Fig.
18—Corvette Heater Core Removal
7. Place a protective covering (waterproof if possible)
over the carpeting under the heater.
8. Remove the two bowden cables from the instrument
panel and disconnect the wiring connectors from the
blower switch and from the resistor.
9. Carefully work the heater assembly out from beneath
the dash.
Core Removal
1.
Remove the heater assembly as described above.
2.
Remove the sheet metal nuts which retain the core
mounting plate to the core housing.
3.
Remove the screws attaching the core brackets to
the core mounting plate and separate the core and
plate. .
Installation
1.
Assemble the core to plate with non-hardening
sealer. Attach the core mounting screws.
2.
Attach the core and plate assembly to the case with
the two sheet metal nuts. The assembly is ready for
installation as described below.
Heater Assembly Installation
1.
Carefully position the heater assembly in place on
inner surface of dash panel, then install the blower
and air inlet assembly on heater studs extending
through to the engine side of the panel. Attach the
seven stud nuts.
2.
Install electrical connectors to the blower switch and
resistor and reinstall the bowden cables to the
instrument panel.
3.
Replace the blower electrical connectors.
4.
Replace the heater hoses. (See Figure 20)
5. Replace the battery and the radiator supply tank.
6. Refill the radiator and check for leakage.
7. Check heater operation and make control adjustments
as necessary.
8. Replace the console panels and the glove
compartment.
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HEATER AND AIR CONDITIONING 1A-11
Fig.
19—Heater and Defroster Cables (Corvette)
CHEVROLET CHASSIS SERVICE MANUAL