1967 CHEVROLET CAMARO Chassis Workshop Manual

HEATER AND AIR CONDITIONING 1A-50

Fig.
64—Receiver-Dehydrator Mounting (Corvette)

3.

4.

5.

6.
To gain access to the blower motor end of the as-

sembly, remove the fender and skirt.

Remove the assembly to firewall attaching screws.

Remove the entire assembly from the vehicle.

Reverse the above procedure when installing the

assembly into the vehicle.

Core Replacement

1.
Disconnect the connections at the suction throttling

valve inlet and the expansion valve outlet. Remove

the expansion valve bulb from the core outlet line.

Cap all open lines. .

Remove the screws attaching the evaporator cover

to the firewall and to the evaporator assembly and

remove the cover.

Remove the screws attaching the core to the assem-

bly and remove the core.

Reverse the above steps for core replacement.

Add three fluid oz. refrigerant after installing a

new core, evacuate and charge the system.
2.

3.

4.

5.

Comfortron

The evaporator assembly is nearly identical to that
of the Four-Season system, and, with the exception of

additional wiring and vacuum hoses, service procedures

are the same.

Chevelle Four-Season System

Removal

•
1.
Purge the system of refrigerant, then remove the

right fender skirt and the hood hinge. Do not remove

the fender.

2.
Disconnect the high pressure line (between the

receiver-dehydrator and the thermostatic expansion

valve) at the expansion valve, and the suction throt-

tling valve to compressor line at the suction throt-

tling valve. Cap and seal all open lines.

3.
Remove the three screws attaching the duct assembly

to the evaporator housing and the blower assembly.

4.
Remove the bolts attaching the evaporator assembly

to the cowl and carefully pull the assembly from the

vehicle. The duct assembly will be removed at this

time also.

Core Replacement

1.
With the evaporator assembly removed from the

vehicle, remove the expansion valve and its bulb.

2.
Remove the four nuts and bolts holding the two

halves of the evaporator housing together and sepa-

rate the halves.

3.
The evaporator core may now be removed.

4.
Leak test the new core and connections, before in-

stalling the core in the housing, by installing the

expansion valve and all refrigerant lines. Connect an

R-12 cylinder to the low pressure compressor gauge

fitting and charge the system to cylinder pressure,

then leak test.

5. After satisfactorily testing the core, install it into

the housing and reassemble the two sides of the.

housing.

Installation

1.
Remove the right trim pad and the screws attaching

the air conditioning duct to the kick panel. This

should allow the duct to be pulled slightly loose from

the kick panel. If not it may be necessary to loosen

the entire duct to obtain the necessary clearance.

2.
Install the evaporator in the cowl being sure that

the duct assembly is in place between an evaporator

housing and the blower assembly.

3.
Replace all bolts and screws.

4.
Move the interior air conditioning duct until sure

that the duct gasket is properly positioned over the

evaporator housing flange. Proper gasket fit at this

point is of great importance.

5. Replace all refrigerant lines.

6. Evacuate and charge the system. Add three fluid oz.

refrigerant oil after installing a new core.

7. Replace the fender skirt and hood hinge.

Universal System All Vehicles

Core and/or Expansion Valve Replacement

Since repairs should never be made on the evaporator

core, a defective unit must be replaced. Before replacing

the core, however, check to be sure that any leaks pres-

ent are not located at the hose connections or expansion

valve connections.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-51

RETAINER

WASHER

GLASS

•O"
RING

Fig.
65-Sight Glass Replacement

Removal

1.
Purge the system.

2.
Disconnect the refrigerant lines at the right rear of

the unit.

3.
Remove the unit from the dash. Disconnect all elec-

trical connectors.

4.
Remove the front cover, withdraw the thermostatic

switch capillary, and separate to the case halves.
5. Remove the clamps from the evaporator inlet and

qutlet pipes.

6. Remove the screws which attach the evaporator to

the case and remove evaporator. '

7. Ljoosen the clamp which mounts the capillary bulb

to the evaporator. Disconnect the inlet and outlet

pipes from the expansion valve and remove the

expansion valve.

Fig.
66—Evaporator Mounting (Chevrolet and Camaro)
Fig.
67—Evaporator Mounting (Chevelle)

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-52

Fig.
68—Wiring and Vacuum Lines—Four-Season (Chevrolet)

Fig.
69-Underhood Wiring-Four-Season (Chevelle)

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-53

Fig.
70—Wiring and Vacuum Lines—Four-Season (Camaro)

Installation

1.
Connect the expansion valve to the refrigerant pipes.

Attach the capillary bulb to the evaporator.

2.
Attach the evaporator to the- case. Attach the inlet

and outlet pipes clamps.

3.
Assemble the case halves. Insert the capillary tube

from the thermostatic switch between the fins as

shown in Figure . Attach the cover plate to the

case.

4.
Mount the unit to the dash and connect the refrigerant

lines.

5.
Evacuate and charge the system. If a new evaporator

was installed, add three fluid ounces of refrigerant

oil to the system before charging.

6. Test system operation.

Chevy II All-Weather System

Removal

Under
the Hood

1.
Purge the refrigerant from the system.

2.
Remove the refrigerant hoses from the evaporator

inlet and outlet connections extending through the

special grommet in the dash panel and into the

engine compartment.

3.
Remove the screw, nut, spacer bracket and grommet

from the outlet connection pipes.
Within the Car

4.
Remove the glove box, ash tray and ash tray

retainer.

5.
Reach through the glove box door to disconnect the

air conditioning "on" door bowden cable (fig. 75).

6. Remove the two shield attaching screws and shield

(A, fig. 76) which covers the lower right evaporator

bracket-to-blower bracket attaching screw (B, fig.

76),
then remove this screw.

7.
Behind the lower left side of ihe evaporator, remove

the evaporator bracket-to-heater distributor bracket

attaching screw (C, fig. 76).

8. Reaching through the glove box door and ash tray

openings, remove the two nuts and washers (D,

fig.
76) attaching the evaporator assembly studs to

the lower instrument panel flange and reinforcement.

9. Disconnect the drain hoses and carefully pull the

evaporator unit toward the rear of the vehicle.

10.
Disconnect wiring connectors (see fig. 77) as nec-

essary and remove the evaporator unit from the

vehicle.

Gore and/or Expansion Valve Replacement

A defective unit must be replaced since repairs should

never be made on the evaporator core. Before replacing

the core, however, check to be sure that any leaks pres-

sent are not located at the hose connections or expansion

valve connections. The following procedure assumes that

the evaporator unit has been removed from the vehicle

as outlined above.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-54

Fig.
71-Wiring-AH Weather (Chevy II)

1.
Loosen the lock screws and remove the two control

knobs from the front of the evaporator unit. Then

use a suitable spanner wrench to remove the two

nuts beneath the control knobs.

2.
Remove the screws (located in the outer ball outlets)

attaching the face plate.to the evaporator case. Then

remove the face plate and, reaching through this

opening, carefully remove the plug attaching the

thermostatic switch capillary tube to the evaporator

core.

3.
Turning the unit over, remove the screws attaching

the back cover and gasket to the case and remove

the cover and gasket.

4.
From the top of the case, remove the screws attach-

ing the evaporator core brackets to the case.

5.
Carefully draw the core and expansion valve assem-

bly out of the case.

NOTE: The air conditioning "on" door bowden

cable, which extends through the core, will also

be removed at this time.

6. Remove the expansion valve power element from

the low pressure line.
7.
Disconnecting the high pressure and low pressure

lines from the valve, remove the valve from the

core.

8. At this point either the expansion valve, evaporator

core or both may be replaced.

a. If replacing the expansion valve, use new etO"

rings and make the connections carefully to

eliminate possible refrigerant leaks. Position

the power element bulb so that it lies flush with

the low pressure line and has the insulating

material properly in place.

b.
If the evaporator core is to be replaced, it will

be necessary to remove the air conditioning

door bowden cable from the core and install it

in the same location in the replacement core.

If no passage has been provided for this purpose

in the replacement core, a pointed instrument

such as a pencil may be forced through core

vanes at the proper location to provide the re-

quired opening. Also remove the spacer bracket,

nut and screw from the inlet and outlet pipes of

the evaporator core and place them in a like

position on the replacement core.

CHEVROLET CHASSIS SERVICE MANUAL

HEATER
AND AIR
CONDITIONING
1A-55

r-TO COMPRESSOR

^GROMMET^-^^Q^S

L.H. REAR—>*<^ >

BRACKET
/>v\j^-""^

A
r—FORWARD

\ BRACKET

*-^"^
\
EVAPORATOR

BLOWER
ASM

\
-BRACE

===:

7—-INSTRUMENT PANEL

f REINFORCEMENT

/

/

f
R.H. REAR
M

BRACKET
m

K BRACKET—^

#INLET
V

M
"6"
RING
\

/
\N

1
-
DASH PANEL—v

GROMMET—^
\

OUTLET—v
A^

J/

X
\—
OUTLET
"O"
RING

A \~-EVAPORATOR

,
&
BLOWER
ASM
INLET

TUBE

Fig.
72—Evaporator Mounting—Universal Unit

9. Replace
the
core
and
valve assembly, with
the
bow-

den cable
in
place,
in the
evaporator case
and
install

the
two
case-to-door bracket attaching screws.

10.
With
the
gasket
in
place, install
the
back cover
of

the evaporator case
and its
attaching screws and
the

seal around
the
evaporator inlet
and
outlet tubes.

11.
Reach through
the
face plate opening
and,
using
the

plastic plug, attach
the
thermostatic switch capillary

tube
to the
evaporator core.

Installation

Within
the Car

1.
Attach system wiring
as
necessary
to the
evaporator

case.

2.
Carefully pass
the
evaporator inlet
and
outlet pipes

through
the
special grommet
in the
dash panel.

3.
Insert
the
evaporator studs through their drilled

holes
in
the
instrument panel flange
and
reinforce-

ment
and,
reaching through
the
glove
box
door
and
ash tray opening, install
the nut
and washer
on
each

stud.

4.
Replace
the
screws attaching
the two
evaporator

case brackets
to
the
blower bracket and distributor

bracket.

5. Replace
the
shield
and
attaching screws protecting

the lower right mounting bracket.

6. Reaching through
the
face plate opening, attach
the

evaporator bowden cable.

7. Replace
the
face plate and attaching screws, feeding

the control knob stems through
the
proper openings

in
the
face plate.

8. Replace
the
control stem bezels
and
control knobs.

9. Replace
the
drain hoses.

10.
Replace
the
glove
box
and
ash
tray.

Under
the
Hood

11.
Replace
the
spacer bracket, screw
and nut on the

CHEVROLET CHASSIS SERVICE /MANUAL

HEATER AND AIR CONDITIONING 1A-56

BLACK & RED

IGNITION—-y^****

SWITCH -"A

/
BLOWER LEAD—^^^

RESISTOR—-" \^<

ASM.
f'

i
'fu^^^^A^^^^^r"G^OUH£>
WIRE

^^
k4

^EVAPORATOR HARNESS

' EVAPORATOR & BLOWER ASM.

Fig.
73—Underdash Wiring—Universal System (Typical)

evaporator outlet pipes. Locate the bracket about

1/2" from the dash panel.

12.
Replace the inlet and outlet hoses and hose clamp

connections.

13.
Evacuate and charge the system. Add three fluid oz.

refrigerent oil after installing a new core.

14.
Check system performance.

Corvette

Replacement (Fig. 78)

1.
Purge the system of refrigerant.

2.
Drain the engine radiator. Then remove the radiator

supply tank from its brackets, the heater water

valve and vacuum line from the firewall, and the

heater hoses from the core pipes. Carefully fold the

hoses,
valve and tank away from the evaporator

case.

3.
Remove the right hand hood lock support.
SCREW DRIVER

(NARROW BLADE) T£

GROOVE

A. Insert screw driver in

tang toward terminal

B. Pry tang back out to

when reinstalled into
RMINAL

\ CONNECTOR

TANG

groove & press

to release.

insure locking

connector.

Fig.
74—Terminal Removal—Universal System

4.
Disconnect the expansion valve equalizer line con-

nection and the evaporator oil bleed line from the

POA.

5.
Disconnect the evaporator outlet to POA inlet

connector.

6. Remove the POA bracket to evaporator case attach-

ing bolts. Then carefully move the valve and its

outlet hose away from the evaporator case.

Fig.
75-Cable Removal-All Weather

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-57

EVAPORATOR PIPES

DISTRIBUTOR RELAY GRD.

ASSEMBLY & WASHER

EVAPORATOR ASM.
BLOWER

SHROUD

(RACKET

(PART OF

BLOWER)

Fig.
76—Evaporator Removal—All Weather

7. Disconnect the thermostatic expansion valve to evap-

orator inlet connector, remove the power element

bulb from the evaporator outlet line and carefully

move .the valve and its inlet hose away from the

evaporator case.

8. Remove the electrical connectors from the relay

and resistor terminals.

9. Remove the screws attaching the evaporator case

cover to the case. See Fig. 79. The core is bracket

mounted to the cover and the entire core and cover

assembly may now be removed from the vehicle.

10.
Remove the two cover to core bracket screws and

separate the core from the cover.

11.
Install the new core to the cover being sure that the

grommets are properly installed around the inlet

and outlet lines.

12.
Reinstall the core and cover assembly into the evap-

orator case and replace the attaching screws.
13.
Reinstall the STV and expansion valves, the equal-

izer line connection and the evaporator oil bleed line

from the STV.

NOTE:
Use all new «O" rings.

14.
Reinstall the radiator supply tank, water valve and

vacuum line, and replace the heater hoses onto the

core pipes being sure not to switch the hoses. Then

refill the radiator.

15.
Add three fluid oz. refrigerant oil after installing a

new core, evacuate and charge the system.

EXPANSION VALVE

The thermostatic expansion valve is factory adjusted

and pre-set and cannot be adjusted after installation. A

malfunctioning valve must be replaced. However, before

proceeding, check all other possible causes of the trouble.

Make certain that the power element bulb is properly

CHEVROLET CHASSIS SERVICE MANUAL