service reset CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

HEATER
AND AIR
CONDITIONING
1A-13

AIR CONDITIONING

INDEX

Page

General Description
1A-13

Four-Season System
1A-13

Controls
1A-16

Comfortron System
. 1A-18

System Components
lA-19

Controls
1A-20

Universal System
. .
1A-21

Chevy
n
All-Weather System
•
1A-21

Corvette Four-Season System
. 1A-22

General Information
. . . 1A-26

Precautions
in
Handling R-12
1A-26

Precautions
in
Handling Refrigerant Lines
1A-28

Maintaining Chemical Stability
in the

Refrigeration System
1A-28

Gauge
Set 1A-29

Charging Station
IA-29

Leak Testing
the
System
1A-29

Vacuum Pump
1A-30

Availability
of
Refrigerant-12
. . 1A-30

Compressor
Oil 1A-31

Compressor Serial Number
1A-31

Inspection
and
Periodic Service
1A-31

Pre-Delivery Inspection
1A-31

6,000 Mile Inspection
1A-32

Periodic Service
, 1A-32

Installing Gauge
Set to
Check System Operation
....
1A-32

Performance Test
1A-32

Performance Data lA-r33

Comfortron System Operational Test
1A-33

Chevrolet Comfortron Tester
1A-34

Complete System Checks
1A-35

Maintenance
and
Adjustments ......
1A-37

Evaporator Comtrol Valve (POA)
.
1A-37
Page

Thermostatic Switch
1A-37

Expansion Valve
1A-41

Engine Idle Compensator
. . .
1A-42

Evacuating
and
Charging Procedures
1A-42

Purging
the
System
1A-42

Evacuating
and
Charging
the
System
1A-43

Checking
Oil . 1A-43

Component Replacement
and
Minor Repair
1A-45

Refrigerant Line Connections
1A-45

Repair
of
Refrigerant Leaks
1A-46

Preparing System
for
Replacement
of

Component Parts
. 1A-46

Foreign Material
in the
System
.
1A-47

Condenser
.
1A-48

Receiver-Dehydrator
1A-48

Evaporator
1A-49

Expansion Valve
1A-57

Evaporator Control Valve (POA)
1A-59

Thermostatic Switch
or
Blower Switch
. .
1A-59

All Weather-Pull Cable
1A-61

Blower Assembly
1A-62

Air Inlet Valve
.
1A-64

Blower
and
Evaporator Assembly
1A-64

Air Distributor Assembly
and
Outlet Ducts ...... 1A-64

Comfortron Automatic Control Components
1A-66

Collision Procedure lA-70

Four-Season Heater Components
1A-73

Comfortron Heater Components
. . . 1A-75

Compressor
1A-76

Wiring Diagrams
1A-78

Special Tools
.
1A-84

GENERAL DESCRIPTION

Four
air
conditioning systems
are
covered
in
this

section. They are:

1.
The
Four-Season System (Chevrolet, Chevelle,

Camaro and Corvette).

2.
The Comfortron System (Chevrolet).

3.
The All Weather System (Chevy n).

4.
The Universal System (Chevrolet, Chevelle, Chevy
n,

Camaro)

Underhood components (that
is, the
compressor,
con-

denser
and
receiver-dehydrator)
are
much
the
same
in

type,
location
and
method
of
attachment
on all of
the

above systems. The six-cylinder reciprocating compres-

sor
is
bracket-mounted
to the
engine
and
belt driven

from
the
crankshaft pulley.
The
condenser
is
mounted

ahead
of the
engine cooling radiator
and the
receiver-

dehydrator
is
mounted
in
the refrigerant line downstream

of
the
condenser.
All
cooling system components
are

connected by means
of
flexible refrigerant lines.

Evaporator size
and
location differ from system
to

system
as do
methods
of
temperature control
and air

supply
and
distribution.

FOUR-SEASON SYSTEM

The Four-Season system used
in the
Chevrolet,

Chevelle, Camaro,
and
Corvette vehicles
may be
iden-

tified
by the
fact that
it
uses
an
evaporator pressure

control known
as the POA
(Pressure Operated Absolute)

suction throttling valve.
Both
the
heating
and
cooling functions
are
performed

by this system.
Air
entering
the
vehicle must pass

through
the
cooling unit (evaporator)
and
through
(or

around)
the
heating unit,
in
that order, and the system
is

thus referred to
as a
''reheat" system.

The evaporator provides maximum cooling
of the air

passing through
the
core when
the air
conditioning sys-

tem
is
calling
for
cooling.
The
control valve acts in the

system only
to
control
the
evaporator pressure
so
that

minimum possible temperature
is
achieved without core

freeze-up.
The
valve
is
preset,
has no
manual con-

trol,
is
automatically altitude compensated,
and non-

repairable.

The heater core will be hot
at
all times since no water

valve
is
present
in
the system.

System operation
is as
follows (See Figure 24 and 25):

Air, either outside
air or
recirculated
air
enters
the

system
and is
forced through
the
system by the blower.

As
the air
passes through
the
evaporator core,
it

receives maximum cooling
if
the
air
conditioning controls

are calling
for
cooling. After leaving
the
evaporator,

the
air
enters
the
Heater
and Air
Conditioner Selector

Duct Assembly where,
by
means
of
manually operated

diverter doors,
it is
caused
to
pass through
or to
bypass

the heater core
in the
proportions necessary
to
provide

the desired outlet temperature. Conditioned airflow then

enters
the
vehicle through either
the
floor distributor

duct
or the
dash outlets. Remember that the heater core

CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-35

Fig.
91—
Removing Carrier Front Support

PINION FLANGE, DUST DEFLECTOR

AND/OR OIL SEAL

Removal

1.
Raise vehicle and place jackstand under frame to

allow wheels to hang free.

2.
Place 1/2" thick block of wood or steel between

carrier upper surface to rear of companion flange,

and body floor. This will prevent carrier assembly

from twisting upward when front support bracket is

disconnected.

3.
Disconnect carrier front mounting bracket bolt from

frame crossmember.

4.
Remove nut from carrier bracket front bolt and

slide bolt to one side until bolt head contacts floor

well. Mark the floor well at this point and drill a

3/4"
diameter hole - remove bolt.

5. Loosen bracket rear bolt and swing bracket down

and to the rear (fig. 91).

6. Disconnect propeller shaft at transmission and at

companion flange. Slide transmission yoke forward,

and lower propeller shaft down and out.

7. Mark companion flange nut and pinion relative loca-

tion.
This is necessary to reset original pinion

bearing pre-load during reassembly of companion

flange.

8. Attach J-8614-1 companion flange holder and remove

flange nut and washer (fig. 92).

9. Remove companion flange by driving off with brass

drift and hammer (fig. 93).

10.
Using screw driver, pry oil seal out of carrier.

Inspection

Inspect companion flange splines for excessive wear

or twisting and check deflector for looseness. If de-

flector is loose or damaged, break stake marks and

remove. Install new deflector and stake in place.

Installation

1.
Place sealing compound around O.D. of new seal

and install seal in carrier using seal Installer

J-21057 (fig. 94).
Fig.
92—Removing Companion Flange Nut

NOTE:
Seal should be started squarely in bore

to eliminate seal distortion.

2.
Tap seal into position until there is a 1/8" gap be-

tween seal flange and carrier (fig. 95).

3.
Lubricate companion flange splines and tap into

place.

4.
Install companion flange washer and nut, and tighten

nut so that it lines up with mark on pinion.

5. Raise propeller shaft into position and connect to

companion flange and transmission yoke.

6. Place rubber cushion on carrier front mounting

bracket and raise bracket into position and loosely

install nut.

7. Install carrier bracket front bolt. With vehicle at

curb,
torque all affected parts to specifications and

install cotter pin to carrier bracket front bolt.

8. Insert a plastic plug from the inside of the floor

well to prevent dust and water entry.

Fig.
93—Removing Companion Flange

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-8

1

FIELD RELAY^I^p2

"LATCH"
^PFN?^

"P1
TERMINAL
JyJvJCTl^

NO. 2 TERMINAD^5^^^«

NO.
3 TERMINAL ^S5«£

NO.
4 TERMINAL ^^^
m

# / VOLTAGE

¥ REGULATOR

1
ACCESS PLUG TO

VOLTAGE ADJUSTMENT

No 4 TERMINAL

Double Contact

Fig.
2c—Voltage Regulator Assemblies
Transistor

regulator to handle the higher field current and enables it

to absorb the increased inductive voltages of the field

coil with satisfactory contact point life.

The double-contact regulator assembly (fig. 2c) con-

sists of a double contact voltage regulator unit and a field

relay unit. This unit uses two sets of contact points on

the voltage regulator unit to obtain desired field excita-

tion under variable conditions. Internal circuit wiring

diagrams of the double contact regulator are shown in

Figures 3c and 4c.

The transistor regulator (fig. 2c) is an assembly com-

posed principally of transistors, diodes, resistors, a

capacitor, and a thermistor to form a completely static

voltage regulating unit in combination with a conventional

vibrating type field relay.

The transistor is an electrical device which limits the
generator voltage to a preset value by controlling the

generator field current. The diodes, capacitor and re-

sistors act together to aid the transistors in controlling

the generator voltage. This is the only function that the

regulator performs in the charging circuit. The

thermistor provides a temperature-compensated voltage

setting. Wiring diagrams of the transistor regulator are

shown in Figures 3c and 4c.

The voltage at which the generator operates is deter-

mined by the regulator adjustment. The regulator voltage

setting can be adjusted externally by removing a pipe plug

in the cover (fig. 2c) and turning the adjusting arm inside

the regulator. This procedure is explained in the followr

ing section, and permits regulator adjustments without

removing the cover.

FUSIBLE

DOUBLE CONTACT
FUSIBLE LINK-^
JUNCTION HORN

BLOCK RELAY

RESISTOR

Q FIELD Q>

DELCOTRON TR-

TRANSISTOR
FUSIBLE LINK-

Fig.
3c-Circuity - Voltage Regulator Assemblies (Except Corvette)

CHEVROLET CHASSIS SERVICE MANUAL

driven disk is sandwiched between the magnetic disk and

a field plate. The field plate forms a returning path for

the magnetic field from the magnetic disk.

The gear drive for the magnetic disk is a 90 degree

nylon gear drive with the driven gear rotating both the

magnetic disK and the speedometer drive cable.

Vacuum Switch, Air Bleed and Filter, and Low

Limit Speed Switch

The end of the shaft from the speed sensing assembly

with the rubber drum extends into the air bleed metering

assembly. This rubber drum has a tang extending from

its surface which allows a set of points to close at a

specific car speed. When the car reaches about 20 mph,

the rubber drum has rotated far enough (moved by the

brass driven disk in the magnetic field) so that its tang

has allowed a spring loaded electrical point to contact

another point. These points are in series with the sole-

noid coil so that under 20 mph, no Regulator operation

is possible.

Surrounding the rubber drum is a "U" shaped spring

clip which is held spread away from the drum by the

nose or cam of the solenoid when the solenoid is in the

relaxed position. The rubber drum and this clip com-

prise the speed clutch of the regulator. When the sole-

noid is energized, the solenoid nose moves toward the

drum and releases the ends of the clip. The clip springs

inward and attaches itself by friction to the drum. Now,
ACCESSORIES 15-5

any change in car speed will rotate the drum and move

the "U" clip just as a speedometer moves its needle.

The top of the MUtf clip is attached to the air bleed valve.

The clip moves a sleeve which slides on the orifice

tube thereby covering and uncovering air ports in the

wall of the tube (the tube inner end is plugged) whenever

car speed changes from the speed at which the solenoid

was energized. The direction of drum rotation is such

that resulting bleed valve operation will cause the Servo

to decrease engine power if the car exceeds the preset

speed and increase engine power if car speed decreases.

The air which passes out the orifice tube enters the

Regulator through the openings in the solenoid housing,

passes through the oil wetted polyurethane filter, and then

enters the orifice tube ports.

When the solenoid is de-energized, the nose retracts

and cams the ends of the "U" clip outward so that it re-

leases the rubber drum.

The solenoid also operates a vacuum switch simul-

taneously with the clutching and declutching of the "U"

clip.
The vacuum switch supplies the Servo unit with

manifold vacuum. The solenoid operated vacuum valve

slides over two ports in the Regulator wall. One port

is connected to manifold vacuum and the other is con-

nected to the center port of the Servo unit. When the

solenoid is de-energized, the valve closes the manifold

vacuum port and opens the Servo port to the inside of

the regulator case. When the solenoid is energized, the

valve connects the Servo port to the manifold vacuum

AAAGNET

SPEED CUP

FIELD PLATE

HAIRSPRING
TO SPEEDOMETER

MAGNET HOUSING

ASSEMBLY
ORIFICE TUBE &

CONNECTOR ASSEM.
CONTROL

VALVE

CLUTCH

SPRING

LOW LIMIT

SPEED SWITCH

RUBBER

DRUM

VACUUM PORT

TO SERVO

INPUT CONNECTION

SOLENOID COIL

SOLENOID AND CLUTCH

HOUSING ASSEMBLY
VACUUM PORT

TO ENGINE

VACUUM VALVE

UNLOCKING CAM

•SOLENOID PLUNGER

AIR FILTER

SIDE VIEW SECTION

REGULATOR DISENGAGED
END VIEW SECTION

ENGAGED

Fig.
8 - Regulator-Cross Section '

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-12

VACUUM

(WIT

P

VACUUM Llh

, AIR SUPPt

LINES

t

SUPERLIFT F

SHOCK ABSO
OPERATED AIR COMPRESSOR

H STORAGE TANK AND

RESSURE REGULATORJV

\A

4E FROM ENG«NE^"^
/ \-HEIGHT CONTROL

•^-Z n VALVE (WITH TIME

^* DELAY MECHANISM)

EAR II

RBERS

Fig.
12 - Automatic Level Control Schematic

sure,
alternatley to opposite sides of the compressor

diaphragm.

As the compressor cycles, the reservoir air pressure

gradually increases causing a back pressure on the sec-

ond stage piston until it equals the push of pressure

against the diaphragm- At this point, a balanced condi-

tion is reached and the unit stops operating. After res-

ervoir pressure drops due to system air usage, the com-

pressor again begins to cycle and replenish the

reservoir.

Pressure balance will depend upon the prevailing mani-

fold vacuum and atmospheric pressure. Both are af-

fected by altitude above or below sea level. Balance

pressure will vary from approximately 150 to 275 psi.

NOTE: After completion of work on this sys-

tem or when servicing other parts of the car and

the system is deflated, inflate the reservoir to

140 psi or maximum pressure available through

the compressor service valve.

The PRESSURE REGULATOR VALVE is preset and

limits the reservoir outlet pressure to approximately 125

psi to avoid damage to the height control valve and Super-

lift shocks.

The HEIGHT CONTROL VALVE, which is mounted on

the frame, senses rear car height through a link attached

to the right rear upper control arm. When load is added

to the car, the overtravel lever is forced up causing an

internal lever to open the intake valve, when this valve

is open high pressure air is admitted to the Superlift

shocks. As the car raises to level, the intake valve shuts

off.

When load is removed from the car, the overtravel

lever is forced down causing the internal arm to open the

exhaust valve. As the car lowers to the level position,

the exhaust valve shuts off.

A four to eighteen second time delay mechanism, which

is built into the height control valve, prevents air trans-

fer due to normal ride movements. The overtravel

lever, which pivots around the control valve shaft, rides

off the flat side of the control valve shaft and does not

have time to. react to the rapid changes or normal ride

motions.
During changes due to loading, the time delay mecha-

nism will allow the overtravel shaft to open either the in-

take or exhaust' valve as required, since this is not a

rapid movement.

The SUPERLIFT shock absorber is essentially a con-

ventional hydraulic unit with a. pliable nylon reinforced

neoprene boot acting as an air chamber.

The unit will extend when inflated and retract when de-

flated by the control valve.

An eight to fifteen psi air pressure is maintained in the

Superlift at all times to minimize boot friction- This is

accomplished by a check valve in the exhaust fitting on

the control valve. Neither shock absorber function nor

conventional ride motions thru rear coil springs is im-

paired in the event of accidental air pressure loss. .

A combination of steel tubing and reinforced rubber

hose is used for air lines throughout the system.

-SUPERLIFT

PORT

STATION WAGON

& SEDAN

INTAKE

PORT
HAUST

PORT

Fig. 13 - Height Control Valve

AIR CHAMBER
BOOT

AIR DOME AIR PISTON

Fig. 14- Superlift Absorber

CHEVROLET CHASSIS SERVICE MANUAL