service CHEVROLET CAMARO 1967 1.G Chassis Manual Online

HEATER AND AIR CONDITIONING 1A-60

Fig.
81-P.O.A. Installation (Camaro)

NOTCH IN SUPPORT

TO ENGAGE SLOT !N VALVE

WHEN VALVE IS ROTATED

TO ANGLE AS SHOWN

Fig.
82-P.O.A. Installation (Chevelle)
Fig.
83—P.O.A. Installation (Corvette)

3.
Remove the electrical connector at the switch to be

replaced.

4.
Remove the switch knob. Remove the switch retain-

ing screws
and:
switch.

Installation

1.
Insert replacement switch into face plate and attach.

2.
Install the switch knob and connect the wiring

connector.

3.
If the thermostatic switch is being replaced, the

capillary tube should be formed to the same shape as

the unit removed.

4.
Attach the capillary to the core (fin sensing type)

and replace the face plate and attaching screws.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-61

INSERT CAPILLARY

BETWEEN FINS AT

ARROW

Fig.
84—Thermostatic Switch Capillary Installation

All-Weather System (Thermostatic Switch Only)

Chevy II

Replacement (See Fig. 85)

1.
Remove both control knobs and control stem bezels

from the evaporator assembly.

2.
Remove the face plate attaching screws located in

the outer ball outlets and lift off the face plate.

3.
Remove the two thermostatic switch attaching

screws.

4.
Disengage the plastic plug attaching the thermostatic

switch capillary tubing to the face of the evaporator

core (fig. 84).

5. Draw the switch out of the case through the face plate

opening, disconnecting the electrical connectors.

6. Reinstall the new switch by reversing the removal

procedure.
Fig.
85—Thermostatic Switch Removal

unit as outlined under
ALL-WEATHER-PULL CABLE

All-Weather System

Chevy II

Removal

1.
Remove the evaporator

EVAPORATOR.

2.
Remove the screws which attach the front and rear

case halves.

3.
Remove clamp from the evaporator pipes and sep-

arate case halves.

4.
Remove face plate retaining screws located in outer

ball outlets.

5. Remove control knobs and retaining nuts.

6. Remove face plate.

7. Remove cable to case retaining screw and thermo-

static switch mounting screw.

8. Remove evaporator to case mounting screws.

9. Withdraw evaporator with cable and thermostatic

switch assembly. Be careful to prevent kinks in the

thermostatic capillary.
10.
Pull the cable out toward the air outlet side of the

evaporator.

Installation

1.
Pass the replacement cable through the same channel

in the evaporator fins. If a new evaporator is being

installed, a channel will need to be opened between

the evaporator fins. This may be done by pushing a

pointed pencil between the fins beginning at the air

outlet side of the core, two inches to the right of the

left side of the fins and between the third and fourth

tubes down from the top. The cable channel should

exit at the air inlet side of the core between the first

and second tubes down from the top.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-62

2.
Insert the evaporator assembly into the outlet case

half and mount the evaporator, thermostatic switch,

and cable to the case.

3.
Install the face plate to the case and install control

retaining nuts and knobs.

4.
Assemble the case halves and mount the evaporator

pipe clamp.

5. Install the evaporator assembly as previously

described under EVAPORATOR.

BLOWER ASSEMBLY

Four-Season System

Chevrolet and Camaro

Removal

1.
Disconnect battery ground cable.

2.
Remove the right front fender and skirt assembly.

3.
Disconnect the motor wire at the flange connector.

4.
Disconnect the rubber air cooling tube from the

motor.

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

move the blower assembly. If the sealer acts as an

adhesive, pry the assembly carefully away from the

6. Remove the blower from the motor shaft.

Fig.
86—Blower Assembly—Four-Season (Chevrolet,

Chevelle, Camaro)
Installation

1.
Mount the blower to the motor shaft with the open end

of the blower away from the motor.

2.
Mount the assembly to the case with the attaching

screws.

3.
Connect the rubber tube and blower wire to the

motor.

4.
Replace the right front fender and skirt assembly.

5. Connect battery ground cable.

Chevelle

The blower assembly (fig. 86) is mounted to the dash

panel and contains the outside air-recirculated air

diverter door, the heating-cooling diverter door, the air

conditioning relay and resistor, the compressor actuating

switch, and the blower motor.

Replacement

1.
Disconnect the blower motor "hot" wire at the con-

nector and the ground lead on the Chevrolet.

2.
Detach the rubber cooling tube from the blower as-

sembly and remove the five bolts attaching the

blower motor to the blower assembly.

3.
Remove the motor and fan, disassemble fan from

motor and install on a new motor. If, because of

engine accessories, hoses restrict lifting the blower

assembly from the engine compartment, remove

blower from motor and lift units out separately.

Assemble replacement units under the restricting

hoses.

4.
Reinstall motor and fan into blower assembly. Re-

place cooling tube, ground wire and connect hot wire

to connector.

5. Check blower operations.

Corvette

Replacement

1.
Remove the radiator overflow tank and brackets and

pull the tank out of the way as far as the length of the

heater hose will permit.

2.
Disconnect the electrical connector and the rubber

air inlet tube from the blower motor.

3.
Remove the five blower flange to case attaching

screws and carefully remove the blower motor and

drum assembly.

4.
Remove the blower drum assembly and reinstall on

a new blower motor.

5. Replace the blower motor and drum assembly in the

case and reinstall all screws, hoses and electrical

connections.

All-Weather System

Chevy II

Removal

Under the Hood

1.
Purge the refrigerant from the system.

2.
Drain the radiator.

3.
Remove the refrigerant hoses at the evaporator

pipes.

4.
Remove the evaporator pipe clamp and grommet.

5. Remove three nuts from the blower case studs which

pass through the firewall.

6. Remove heater hoses from core tubes.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-63

Under Dash

7. Remove ash tray and retainer, and glove box.

8. Remove blower case to air inlet adapter bracket

retaining screw.

9. Remove screw attaching air distributor to firewall.

10.
Remove nuts retaining evaporator case to lower lip

of dash. Withdraw evaporator drain tubes.

11.
Lower complete heater - air conditioning assembly.

12.
Remove screw retaining blower case to air distrib-

utor and separate them.

13.
Remove blower to case attaching screws. Disconnect

motor wire and remove blower assembly.

14.
Remove blower from motor shaft.

Installation

1.
Assemble blower to motor shaft.

2.
Mount motor in blower case and connect wire.

3.
Assemble blower case to air distributor and install

retaining screw.

4.
Lift the complete assembly into place and install

attaching screws and nuts.

5. Replace ash tray retainer and tray and glove box.

6. Replace nuts (engine side of dash) on heater case

studs and connect heater hoses.

7. Replace evaporator pipe clamp and grommet.

8. Replace the refrigerant hoses.

9. Evacuate and charge the refrigeration system and

refill the cooling system.

10.
Check system performance.

Universal Blower Assembly

Removal

1.
Remove the universal unit from its dash mounts.

2.
Remove the cover plate and separate the upper and

lower case halves. Remove blower motor mounting

strap screw and swing strap outward.

3.
Remove blower assembly. Loosen the blower wheel

setscrews and remove the wheels from the motor

shaft. . ' .
Fig.
88-Air Inlet Assembly (Chevrolet)

Installation

1.
Install the blower wheels on the motor so that the

lower blades curve toward the firewall side of the

unit when the motor is placed in the case. Tighten

the setscrews.

2.
Place the motor in the bracket with the electrical

connector side of the motor to the right side of the

bracket. Attach the mounting strap.

3.
Assemble the case halves and attach the cover plate.

4.
Remount the unit to the dash.

Fig.
87—Blower Assembly—Universal System
Fig.
89—Air Doors (Camaro)

CHEVROLET CHASSIS SERVICE

HEATER AND AIR CONDITIONING 1A-64

Fig.
90—Evaporator Wiring (Corvette)

AIR INLET VALVE

Four-Season System

Chevrolet

Figure 88 illustrates the vacuum valve which controls

the air inlet operation of the Four-Season System.

A vacuum tank and check valve is used to assure that

the air door will not change its position due to variations

in engine vacuum.

Camqro

Figure 89 illustrates the outside air inlet door assem-

bly, and the door in the kick pad which admits reeir-

culated air to the system.
BLOWER AND EVAPORATOR ASSEMBLY

(Corvette)

Replacement

1.
Remove the evaporator core as outlined under

"Evaporator Core Replacement".

2.
Remove the blower motor as outlined under "Blower

Motor Replacement".

3.
Remove the heater and air conditioning distributor

as outlined under "Air Distributor Duct Removal".

4.
Remove the remaining nuts attaching the blower

and evaporator assembly and the cover assembly

to the studs on the -firewall.

5. Replace the components removed by reversing the

removal, procedure.

AIR DISTRIBUTOR ASSEMBLY

AND OUTLET DUCTS

Four Season System

Chevrolet and Chevelle

Figures 92 through .95 illustrate the air distributor and

outlet ducts as used in the Chevrolet, Chevelle, Camaro,

and Corvette.

Corvette

Right Outlet Duct

Removal

1.
Remove the clamp screw at the inner end of the

outlet duct and loosen the clamp.

2.
Remove the screw and lock washer attaching the

duct outer mounting tab to the body hinge pillar

brace.

3.
Pull the duct and clamp down and away from the

distributor assembly. Disconnect the courtesy light.

4.
The duct extension assembly may now be removed

if desired as well as the deflector assembly. See

Figure 95.

AIR COND.

PULL
AIR PULL- DEFROSTER

FAN PULL HOT PULL

Fig.
91—Corvette Four-Season Controls

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-65

Fig.
92—Chevrolet Four-Season Ducts

Installation

Reverse

assembly.
the removal procedure to reinstall the duct

Left Outlet Duct

Removal

1.
Remove the two parking brake lever bracket to

dash brace attaching screws and move the lever and

cable so they will not interfere with the duct

removal.

2.
Remove the screw and lock washer attaching the duct

outer bracket to the hinge pillar support.

3.
Remove the screws and lock washers attaching the

duct assembly to the dash brace bracket.

4.
Carefully pull the outer end of the duct downward,

detaching the courtesy light from its bracket.

5. Loosen the screws clamping the outlet duct to dis-

tributor assembly flexible tubing at the outlet duct.

The outlet duct may now be removed from beneath

the instrument panel.

6. The duct extension assembly and the deflector as-

sembly may be removed, if desired, as seen in

Figure 95.

Installation

The duct assembly is installed by reversing the re-

moval instructions.

Center Outlet Duct

Removal

1.
Remove the right and left console trim panels.

2.
Remove the radio receiver.

3.
Remove the electric clock.
4.
Remove the knobs, nuts and bezels from the two

air conditioning controls above the clock, AIR COND.

PULL and COLD IN-HOT PULL.

5. Carefully pull the outlet duct and control cables

loose from the rear of the center console and work

it down and out from under the dash. The left hand

control cable runs through the left hand flexible

tubing and may be left in the tubing after it is dis-

engaged from the duct. The right hand control cable

must also be pulled from the duct assembly as the

duct is removed.

6. The center deflector barrel assembly may now be

removed if necessary. Snap off the hairpin clips to

remove the barrel and spacer washers.

Installation

Reverse the removal procedure for installation.

AIR DISTRIBUTOR ASSEMBLY

Removal

1.
Drain the cooling system radiator.

2.
Remove the heater hoses from the core pipes and

remove the cover attaching nuts and cover surround-

ing the core pipes.

3.
Remove the glove compartment assembly and the

glove compartment door.

NOTE:.
See "Section 1 - Body" for removal

and installation of body items.

4.
Remove the right kick pad.

5. Remove the right and left center console trim panels.

6. Remove the radio receiver assembly.

7. Remove the defroster duct.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-66

Fig.
93—Chevelle Four-Season Ducts

8. Remove the radio speaker and grille.

9. Remove the right outlet duct.

10.
Disconnect the bowden cables from their brackets

and operating levers on the distributor assembly.

11.
Disconnect the flexible tubing from the center and

left side outlet ducts at the air distributor assembly.

12.
Remove the heated air distributor ducts from the

air-distributor assembly.

13.
Remove the single remaining distributor to dash

panel attaching nut (the others were removed from

beneath the hood when the core cover was removed

in Step 2) located at the right end of the air dis-

tributor assembly.

14.
Carefully pull the assembly out from under the

dash, disconnecting the compressor switch wiring

connector and the water valve control switch vacuum

lines.
Installation

Reverse the removal procedure to reinstall the air

distributor assembly.

COMFORTRON AUTOMATIC

CONTROL COMPONENTS

The Comfortron system is the same as the Chevrolet

Four Season system insofar as the basic system compo-

nents are concerned. , Most removal and installation

procedures wUl remain as stated for the Four Season

system except where the automatic control components

are encountered. Each such component will be covered

in the pages which follow.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-67

Fig.
94—Camaro Four-Season Ducts

Heater and Air Distributor Assembly

Removal

rfooo

1.
Disconnect battery ground cable.

2.
Drain radiator (do not purge refrigerant system).

3.
Disconnect all connectors attached to the Comfortron

wiring harness which are on the engine side of the

firewall. Push the wiring harness grommet through

the firewall to the rear.

4.
Disconnect the four vacuum hoses coming from the

underdash through the large firewall grommet. Push

the hose grommet through the firewall to the rear.

5.
Remove the nuts from the heater and air distributor

case studs which project through the firewall from

the dash side.

6. Disconnect the heater hoses from the core tubes.

Under Dash

1.
Remove glove box assembly.

2.
Remove the dash center face plate, ash tray assem-

bly, and any radio and/or tape equipment.

3.
Remove the Comfortron control assembly mounting

screws and lower the control unit.
4.
Remove the vacuum line from the kick pad valve

diaphragm.

5.
Disconnect all harness connectors between the Com-

fortron harness and the rest of the dash wiring.

6. Remove the air distributor duct which supplies the

dash outlets.

7.
Remove the screws attaching the heater and air

distributor to the firewall.

8. Pull the assembly rearward then down to remove

from the dash. Pull the Comfortron wiring harness

and vacuum hose assembly through the firewall.

Installation

1.
Place the entire case assembly with wiring, vacuum

hoses,
and control assembly into the car on the floor.

2.
Pass the underhood wiring harness and vacuum hose

harness as far as possible through the appropriate

firewall holes.

3.
Lift the assembly up into position and pass the case

studs through the firewall mounting holes. Attach

the case to the firewall with the mounting screws.

4.
Mount the dash outlet air distributor duct to the face

of the case.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-68

Fig.
95—Corvette Four-Season Ducts

5. Connect the various Comfortron harness connectors

to the dash wiring and connect the vacuum hose to

the kick pad valve diaphragm. Push the vacuum hose

harness and wiring harness through the firewall to

the proper location and install their respective

grommets.

6. Raise the control unit into place and install the

mounting screws. Check that all connections are

complete.

7. Replace any radio and/or tape equipment, the ash

tray assembly, and face plate.

8. Replace the glove box assembly.

9. Connect the heater hoses to the core tubes, and

attach the nuts to the case studs through the firewall.

10.
Reconnect the four vacuum hoses as follows: Purple

to the cylinder on the thermo-vacuum valve, yellow

tracer to the body of the thermo-vacuum valve, red

tracer to the vacuum source "Tee" connection, and

white tracer to the vacuum tank inlet.

11.
Connect the wiring harness to the underhood air

conditioning components.

12.
Refill cooling system, connect battery ground cable

and check system performance.

Vacuum Tank

The vacuum tank is mounted on the firewall as shown

in Figure 97. Notice that the two vacuum lines are

clamped to the vacuum tank ports. *

Thermal Vacuum Valve

This heat operated vacuum valve is located in the

heater core input line. Figure 98 illustrates valve instal-

lation with clamps attaching the water hoses as well as

the vacuum hoses in place.
Resistor Assembly

Figure 99 illustrates the location and installation of

the blower speed resistor assembly.

Relays

Two relays are used in the system, both mounted on the

evaporator case as shown in Figure 100. The mounting

bracket forms a common ground for the relays and as a

plug for the hole in the evaporator housing used in the

Four Season system for resistor installation.

Sensors (Thermistors)

Ambient Switch and Sensor

This combination unit, which engages the compressor

clutch at about 40°F and also senses outside air tem-

perature and sun load, is mounted to the firewall within

the engine compartment with its long neck extending

deep into the cowl vent plenum chamber. Figure 98 il-

lustrates this installation,

In-Car Sensor

This sensor is located beneath the lip of the instru-

ment panel overhand just to the right of the driver as

shown in Figure 101.

Removal

1.
Remove glove box assembly.

2.
Disconnect sensor wires connector at harness.

3.
Remove sensor mounting screws, remove sensor

and pull wires and connector through hole in dash.

Installation

1.
Insert connector and

through the dash hole.
wires of replacement sensor

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-69

Fig.
96—Refrigerant and Vacuum Hoses (Corvette)

2.
Mount the sensor to the dash and connect the wires

to the Comfortron harness.

3.
Replace glove box assembly.

Control Head

The control head is attached to the instrument panel

flange in the same manner as the Four Season Control

Panel (See Figure 105). Two screws hold the head in

place. The amplifier, blower switch and servo and

defrost control cables are all part of the control head.

Amplifier

After the control head is removed from the instrument

panel, the amplifier may be removed as shown in Figure

107.

Temperature Dial Adjustment

1.
Install Tester J-22368 as previously described.

2.
Set Tester Voltage switch to Control Calibrate

position.

3.
Start the engine (fast idle) and set Comfortron

Control lever to HI-FRONT.

4.
Switch Rocker switch to MANUAL.

5. Set Manual Control Knob to 150 ohms on scale.

6. Rotate the Control Head Temperature Dial until the

voltmeter on the tester reads 6.5 volts. The Tem-

perature Dial should now indicate 75°.

7. If the Temperature Dial does not indicate 75°, insert

Tool J-21530 in slot to the left of the Dial as shown

in Figure 106.

8. With tool in position, rotate the Temperature Dial

so that it indicates 75°F.

Transducer

Figure 104 illustrates the installation of the transducer

assembly. Vacuum lines are clamped to the transducer

vacuum ports.
Fig.
97—Comfortron Vacuum Tank

CHEVROLET CHASSIS SERVICE JWANUAl