1967 CHEVROLET CAMARO cooling

HEATER AND AIR CONDITIONING 1A-42

EXTERNAL

EQUALIZER LINE

Fig. 54—Thermosratic Switch Adjustment

POORLY LOCATED POWER ELEMENT BULB

Normal Pressure.

Poor Cooling.

ENGINE IDLE COMPENSATOR

This additional aid to prevent stalling during prolonged

hot weather periods is included with all air conditioned

vehicles. The idle compensator is a thermostatically

controlled air bleed which supplies additional air to the

idle mixture. On V-8 engines, with factory installed air
Fig. 55—Expansion Valve

conditioning systems, the compensator is located within

the carburetor and is accessible when the engine air

cleaner is removed. On all other vehicles the compen-

sator is threaded into a manifold, fitting below the

carburetor. All compensators are factory set and are

non-adjustable. A malfunctioning unit should be replaced.

NOTE:
If engine idle is erratic, hold the idle

compensator valve closed with a pencil or

wooden dowel while adjusting the idle mixture

screw(s). Never attempt to bend the bimetal

strip or attempt any valve adjustment.

EVACUATING AND CHARGING PROCEDURES

1967 AIR CONDITIONING SYSTEM CAPACITIES

Four-Season Systems (Chevrolet and Chevelle)

Universal System (Chevrolet, Chevelle and Camaro)

Universal and All-Weather System (Chevy II)
Refrigerant Charge

3 lbs., 12 oz.

3 lbs.

2 lbs., 8 oz.
Oil Charge

11 ozs. 525 viscosity

11 ozs. 525 viscosity

11 ozs. 525 viscosity

PURGING THE SYSTEM

In replacing any of the air conditioning components the

system must be completely purged or drained of re-

frigerant. The purpose is to lower the pressure inside

the system so that a component part can be safely

removed.

1.
With engine stopped install high and low pressure

lines of gauge set to the proper high and low pres-

sure gauge fittings (see "Installing Gauge Set to

Check Operation").
2.
With plug removed from the centerline on the gauge

manifold, open high pressure gauge valve and dis-

charge the vapor slowly through the center

connection.

CAUTION: Do

compressor

refrigerant.
not open valves too much or

oil may be discharged with the

A rag wrapped around the end of

the center gauge line will prevent the splashing

of oil in the event of accidental rapid discharge.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-43

LOW PRESSURE

CONTROL
HIGH PRESSURE

CONTROL

3

VACUUM

CONTROL
4

FREON

CONTROL

Fig,
56—Charging Station Controls

3.
When the pressure is reduced to below 100 pounds

on the high pressure gauge, open the low pressure

gauge valve and continue discharging until all re-

frigerant has been released. Close both gauge valves.

EVACUATING AND CHARGING THE SYSTEM

GENERAL NOTE: La all evacuating procedures

shown below, the specification of 26-28 inches

of Mercury vacuum is used. These figures are

only attainable at or near Sea Level Elevation.

For each 1000 feet above sea level where this

operation is being performed, the specifications

should be lowered by 1 inch. Example: at 5000

ft. elevation, only 21 to 23 inches of vacuum can

normally be obtained.

Whenever the air conditioning system is open for any

reason, it should not be put into operation again until it

has been evacuated to remove air and moisture which

may have entered the system.

The following procedures are based on the use of the

J-8393 Charging Station.

Filling Charging Cylinder

1.
Open control valve on refrigerant drum.

2.
Open valve on bottom of charging cylinder allowing

refrigerant to enter cylinder.

3.
Bleed cylinder valve on top (behind control panel) as

required to allow refrigerant to enter. When re-

frigerant reaches desired level (see "Air Condition-

ing System Capacities"), close valve at bottom of

cylinder and be certain bleed valve is closed

securely.

NOTE: It will be necessary to close bleed valve

periodically to allow boiling to subside to check

level in sight glass.

Installing Charging Station to System

1.
Be certain all valves on charging station are closed.

2.
Connect high pressure gauge line to high pressure

gauge fitting. (See "Installing Gauge Set to Check

System Operations.")
3.
See Figure 56. Turn high pressure control (2) one

turn counter-clockwise (open). Crack open low pres-

sure control (1) and allow refrigerant gas to hiss

from low pressure gauge line for three seconds,

then connect low pressure gauge line to low pressure

gauge fitting.

4.
System is now ready for performance testing.

Evacuating and Charging System

1.
Install charging station as previously described.

Refer to Figure 56 and 57 while performing the

following operation.

2.
Remove Low Pressure gauge line from compressor.

3.
Crack open high (2) and low (1) pressure control

valves, and allow refrigerant gas to purge from

system. Purge slow enough so that oil does not

escape from system along with Refrigerant.

4.
When refrigerant flow stops, connect Low Pressure

gauge line to compressor.

5.
Turn on vacuum pump and open Vacuum Control

Valve (3).

6. With system purged as above, run pump until 28-29

inched of vacuum is obtained. Continue to run pump

for 15 minutes after the system reaches 28-29 inches

vacuum.

7.
If 28-29 inches cannot be obtained, close Vacuum

Control Valve (3) and shut off vacuum pump. Open

Refrigerant Control Valve (4) and allow 1/2 pound of

R-12 to enter system. Locate and repair all leaks.

8. After evacuating for 15 minutes, add 1/2 pound of

R-12 to system as described in Step 7 above. Purge

this 1/2 pound and reevacuate for 5 minutes. This

second evacuation is to be certain that as much con-

tamination is removed from the system as possible.

9. Only after evacuating as above, system is ready for

charging. Note reading on sight glass of charging

cylinder. If it does not contain a sufficient amount

for a full charge, fill to the proper leveL

10.
With High and Low pressure Valves (1 and 2) open,

close Vacuum Control Valve (3) and open Freon

Control Valve (4). Operating the heater and air

conditioner blower with the controls set for cooling

will help complete the charging operation.

NOTE: If the charge will not transfer com-

pletely from the station to the system, close

the high pressure valve at the gauge set, set

the air conditioning controls for cooling, check

that the engine compartment is clear of ob-

structions, and start the engine. Compressor

operation will decrease the low side pressure

in the system.

System is now charged and should be performance

tested before removing gauges.

CHECKING OIL

In the six cylinder compressor it is not recommended

that the oil be checked as a matter of course. Gener-

ally, compressor oil level should be checked only where

there is evidence of a major loss of system oil such as

might be caused by:

• A broken refrigerant hose.

• A severe hose fitting leak.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-45

• A very badly leaking compressor seal.

• Collision damage to the system components.

As a quick check on compressor oil charge, with the

engine off, carefully crack open the oil drain plug on the

bottom of the compressor. If oil comes out, the com-

pressor has the required amount of oil To further check

the compressor oil charge, should the above test show

insufficient oil, it is necessary to remove the compressor

from the vehicle, drain and measure the oil.

Checking Compressor Oil Charge

1.
Run the system for 10 minutes at 500-600 engine

rpm with controls set for maximum cooling and

high blower speed.

2.
Turn off engine, discharge the system, remove

compressor from vehicle, place it in a horizontal

position with the drain plug downward. Remove the

drain plug and, tipping the compressor back and

forth and rotating the compressor shaft, drain the

oil into a clean container, measure and discard the

oiL

3.
a. If the quantity drained was 4 fluid oz. or more,

add the same amount of new refrigerant oil to

the replacement compressor.

b.
If the quantity drained was less than 4 fluid oz.,

add 6 fluid oz. of new refrigeration oil to the

replacement compressor.

c. If a new service compressor is being installed,

drain all oil from it and replace only the amount

specified in Steps 3a and 3b above.

d. If a field repaired compressor is being installed,

add an additional 1 fluid oz. to the compressor.

4.
In the event that it is not possible to idle the com-

pressor as outlined in Step 1 to effect oil return to

it, proceed as follows:

a. Remove the compressor, drain, measure and

discard the oil.

b.
If the amount drained is more than 1-1/2 fluid

oz.
and the system shows no signs of a major

leak, add the same amount to the replacement

compressor.

c. If the amount drained is less than 1-1/2 fluid oz.

and the system appears to have lost an excessive

amount of oil add 6 fluid oz. of clean refrigeration

oil to replacement compressor, 7 fluid oz. to a

repaired compressor.

If the oil contains chips or other foreign ma-

terial, replace the receiver-dehydrator and flush
or replace all component parts as necessary. Add

the full specified volume of new refrigeration oil

to the system.

5.
Add additional oil in the following amounts for any

system components being replaced.

Evaporator 3 fluid oz.

Condenser . . . . ... . . . . . . 1 fluid oz.

Receiver-Dehydrator ....... 1 fluid oz.

NOTE: When adding oil to the compressor, it

will be necessary to tilt the rear end of the

compressor up so that the oil will not run out

of the suction and discharge ports. Do not set

the compressor on the shaft end.

Adding Oil to the System

The system should be completely assembled and un-

charged before adding oil. Use only uncontaminated

refrigerant oil (525 viscosity) and add as follows:

1.
Connect the low pressure line from the gauge set

to the low pressure gauge fitting on the P.O.A.

valve (Four-Season) or low pressure fitting on the

compressor connector Mock (Universal System).

2.
Connect the high pressure line from the charging

station gauge set to the compressor muffler or high

pressure side of the connector block.

3.
Disconnect the high pressure line from the gauge set,

make certain that the line is clean, and place the

end in a graduated container.

4.
Pour enough refrigerant oil into the container so

that the required volume may be drawn into the

system by the high pressure hose.

5.
Close the high pressure valve at the gauge set,

and open the low pressure valve.

6. Operate the vacuum pump to drop the pressure within

the system and cause atmospheric pressure to force

oil through the high pressure line into the system.

When the oil level has dropped the required volume,

pull the line out of the oil container and continue

vacuum pump operation to force the oil contained

in the line into the system.

7.
Shut off the vacuum pump and connect ttye high

pressure line to the gauge set. Open the high

pressure valve and evacuate the system through

the high and low pressure sides of the system.

Complete the charging operation as outlined in Step

10 under "Evacuating and Charging System".

COMPONENT REPLACEMENT AND MINOR REPAIRS

REFRIGERANT LINE CONNECTIONS

"O"
Rings

Always replace the "O" ring when a connection has

been opened. When replacing the "O" ring, first dip it

in refrigeration oil. Always use a backing wrench on

"O"
ring fittings to prevent the pipe from twisting and

damaging the "O" ring. Do not overtighten. Correct

torque specifications are as follows:
Metal

Tube

O.D.

1/4

3/8

1/2

5/8

3/4
Thread and

Fitting

Size

7/16

5/8

3/4

7/8

1-1/16
Steel

Tubing

Torque*

13

33

33

33

33
Alum.

Tubing

Torque*

6

12

12

20

25

* Pound Feet

CHEVROLET CHASSIS SERVICE

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-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-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-74

Fig.
108—Comfortron Power Servo Installation

4.
Disconnect heater' hoses from heater core (at

firewall).

5. Remove glove box door.

6. Remove glove box interior.

7. Disconnect right, left, and center air conditioning

outlet hoses from distributor duct.

8. Remove air distributor duct from heater

housing.

9. Disconnect hose and cable clamps from heater

housing.

10.
Remove the remaining three heater housing stud

retaining nuts (engine compartment) and one upper

retaining screw (inside vehicle).

11.
Pull the unit away from the firewall and out of the

car.

ADJUSTMENT

SCREW

Fig.
109—Mode Shift Vacuum Diaphragm
Fig. 110'—Compressor Mount—L-6 Engines (Typical)

12.
Remove heater.housing cover from heater housing.

13.
Remove heater core from heater housing cover by

removing four (4) retaining screws and two "U"

clamps.

14.
Remove heater core.

Installation

1.
Replace core in case using a non hardening sealer.

Attach the core clamps and retaining screws.

2.
Attach the heater housing cover to the housing.

3.
Position the unit against the firewall and attach

it with the retaining screw at the top of the case.

4.
Attach the sheet metal nuts to the case studs which

project through the firewall to the engine side.

5. Connect the control cables to the control doors and

case.

6. Attach the air distributor duct to the case.

7. Connect the left, right, and center outlet hoses.

8. Replace the glove box assembly.

9. Connect heater hoses to core tubes.

10.
Replace fender assembly.

11.
Fill cooling system and connect battery cable.

Camaro

Lower Heater Hose

Removal

1.
Drain radiator.

2.
Remove side mouldings and retainers.

3.
Remove lower fender attaching bolts.

4.
Remove skirt to fender and skirt to reinforcement

bolts.

5. pry the skirt away from the fender flange and away

from the firewall. Block the skirt (four inchlengtti

of 2 x 4) clear of the lower hose and proceed with

the hose replacement.

Installation

1.
Connect the hose.

2.
Remove the block, move the skirt into position and

install all attaching bolts.

3.
Replace fender attaching bolts and mouldings.

4.
Refill cooling system.

CHEVROLET CHASSIS SERVICE MANUAL