1967 CHEVROLET CAMARO Chassis Workshop Manual

HEATER AND AIR CONDITIONING 1A-2

DEFROSTER-q

DOOR
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HEATER
OUTLET
DEFROSTER
OUTSIDE
AIR
FROM PLENUM

OUTLETS
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BLOWER
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AIR
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DOOR
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HEAT
DOOR
HEATER

CORE

Fig. 2-Heater Schematic (Chevy 11)

CHEVY
II

Heater components are located under the instrument

panel in the passenger compartment. Hot water hoses

from the engine are routed to the fire wall to the heater

core pipes. The blower motor receives outside air from

the cowl vent plenum chamber through the adapter as-

sembly. The air enters the heater core chamber where

it either bypasses or passes through the core depending

on the position of the temperature door, controlled by

the TEMPERATURE lever on the instrument panel.

Temperature control is achieved by adjusting the position

of this door to vary the proportion of heated and unheated

air introduced to the car interior. As the air flow is

drawn out of the heater core chamber (in the desired

proportion of hot and cold), it enters the blower where

it is thoroughly mixed, assuring a uniform temperature.

The distributor guides the air flow through either the

floor outlet or the defroster outlets depending on the

setting of the DEFROSTER lever on the instrument

panel. The AIR-FAN lever is the air OFF control as

well as the blower control.

CONTROLS

Control Assembly (Chevrolet, Chevelle, Camaro,

and Chevy II)

Air-Fan Lever

Since the heater makes use of outside air only, this

lever serves as an "air on or off" control by actuating

a damper in the distributor assembly downstream ("up-

stream" in the Chevy n heater) from the blower assem-

bly. With the lever in the half-way position, this damper

will be open to allow airflow into the vehicle. Moving the

lever further will actuate the three-speed (LOW-MED-

HIGH) fan lever which controls the blower motor and

determines the volume and force of the air flowing

through the heater core into the car.

Temperature Lever

Through its bowden cable, this lever controls the
positioning of the temperature door in the distributor

duct. This door allows airflow through either the heater

core (full RIGHT) or the bypass duct around the heater

core (full LEFT). Because the water temperature is con-

stant, this knob acts as an air mixture control, control-

ling temperature by varying the proportions of heated

and unheated air blended in the heater distributor duct.

The cam lock device at the damper door operating

lever (Chevelle only) may be adjusted as follows: Loosen

the two attaching screws. Place the cam in the closed

position and insert a pin through holes provided, locking

the cam in this position. Rotate the entire assembly

toward the closed position. Hold closed with some force

and tighten attaching screws. Remove the locking pin.

Defrost Lever

The defrost lever controls the position of the damper

(or deflector) door located in the heater and defroster

assembly. In the "off" position full airflow will go to

the floor duct for car heating purposes. In the "de-ice"

position the diverter door will drop down and divert

almost all the airflow to the defroster duct. (This posi-

tion will seldom be needed except for extreme de-icing

requirements). A "detent" position is built into the

Fig. 3—Heater Control Panel (Chevrolet Shown as Typical)

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-3

linkage of this lever which will provide partial airflow

only to the defroster duct and which should be used for,

all normal defogging operations.

CORVETTE

Heater components are attached to the dash panel on

the right side of the vehicle with the air inlet assembly

on the engine side and the heater and air distributor

assemblies beneath the instrument panel within the pas-

senger compartment.

The heater operates on outside air only with the blower

receiving its air flow from the cowl vent plenum

chamber.

No water valve is utilized in the system. Therefore,

water flows through the heater core constantly while

the engine is running, keeping the core at maximum

temperature at all times.

Airflow through the system is shown in Figure 1.

Controls

Two knobs control all heater operations:

The FAN-TEMP knob is rotated to turn the blower

on and off and control blower speed and is pulled out

as desired to regulate heater temperature.

The AIR-DEF knob is the air on-and-off control as

well as the defroster control.

Temperature Damper: Door

At the heart of the heater operation is the temperature

damper door. Air from the blower follows parallel paths

through the distributor duct, with one path passing

through the heater core and the other path bypassing the

core.

The temperature damper door is placed in the duct

so that, when closed, the path of the heated air leaving

the heater core is blocked while the ambient air path

remains open. Positive closing of this door when no

heat is being called for is assured by a cam assembly

at the door operating lever. As the FAN-TEMP knob

is pulled out, the damper door is opened accordingly,

allowing varying proportions of heated air to mix with

the unheated airflow, thus providing heater outlet tem-

perature control. With the knob pulled fully out the
Fig.
4—Heater Controls (Corvette)

ambient air path is blocked and all airflow passes

through the heater core. Final heater output temperature

is dependent upon the proportion of heated and ambient

air blended together according* to the setting of the

temperature damper door.

Air and Defrost Damper Doors

Beyond the temperature damper door are the air door

and the defroster door, both operated through a single

bowden cable by the AIR-DEF knob. The first half of the

travel of this knob opens the AIR door allowing the

airflow to pass into the interior of the car through the

floor distributor openings. Pulling the AIR-DEF knob

fully out causes the defroster door to open, diverting

this airflow to the defroster ducts for defogging, de-

frosting or deicing operations.

NOTE: Since this knob is the air on-or-off

control, it should be pulled at least halfway out

before turning on the blower.

Fan Control

Rotate the FAN-TEMP knob to operate the three-

speed blower, increasing the velocity of the air through

the heater. The fully counter-clockwise position of the

knob is the off position. Turn clockwise to the desired

blower speed; fully clockwise for high blower speed.

COMPONENT REPLACEMENT AND REPAIR

CHEVROLET, CHEVELLE, AND CAMARO

Blower Assembly

Removal

1.
Disconnect battery ground cable.

2.
Unclip heater hoses from fender skirt.

3.
(Chevrolet and Camaro) Remove right front fender

and skirt assembly. (See Section 11 of the Service

Shop Manual)

(Chevelle) Move the vehicle front wheels to the

extreme right turn position. Remove all right front

fender retaining bolts. Allow the skirt to drop and

rest on top of the tire. To gain maximum clearance

for access to the blower motor attaching screws, a

block of wood may be wedged between the fender

lower flange and the top of the fender skirt. Position

the wood block so that the rear portion of the skirt

will be forced down and inboard. (See Figure 7.)
4.
Disconnect the blower motor wire at the motor

flange.

5.
Remove the motor to case mounting screws and re-

move motor. Pry the flange gently if the sealer acts

as an adhesive.

6. Remove the blower wheel retaining nut and separate

blower and motor.

Installation

1.
Assemble the blower wheel to the motor with the

open end of the blower away from the motor.

2.
Place the assembly into the case and replace the

mounting screws. Connect the blower motor wire to

the motor.

3.
(Chevrolet and Camaro) Replace the fender and

skirt assembly.

(Chevelle) Replace the fender skirt.

4.
Clip the heater hoses to the fender skirt and connect

the battery ground cable.

CHEVROLET CHASSIS SERVICE MANUAL

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

CHEVROLET CHASSIS SERVICE MANUAL

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.

CHEVROLET CHASSIS SERVICE MANUAL

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.

CHEVROLET CHASSIS SERVICE MANUAL

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

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)

CHEVROLET CHASSIS SERVICE MANUAL

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

CHEVROLET CHASSIS SERVICE MANUAL