HEATER AND AIR CONDITIONING 1A-32
5.
Check hose clamp connections. If clamp screw torque
is less than 10 lb. in., retighten to 20-25 lb. in. Do
not tighten to new hose specifications or hose leak-
age may occur.
6. If there is evidence of an oil leak, check the com-
pressor to see that the oil charge is satisfactory.
7.
Check the system controls for proper operation.
6000 MILE INSPECTION
1.
Check unit for any indication of a refrigerant leak.
2.
If there is an indication of an oil leak, check the
compressor proper oil charge.
3.
Check sight glass for proper charge of Refrigerant-
12.
4.
Tighten the compressor brace and support bolts and
check the belt tension.
5.
Check hose clamp connections as in step 5 above.
6. Check thermostatic switch setting (Universal and
All-Weather Systems.)
PERIODIC SERVICE
• Inspect condenser regularly to be sure that it is not
plugged with leaves or other foreign material.
Fig.
46—Compressor Connector Block—Typical
• Check evaporator drain tubes regularly for dirt or
restrictions.
• At least once a year, check the system for proper
refrigerant charge and the flexible hoses for brittle-
ness,
wear or leaks.
• Every 6000 miles check sight glass for low refriger-
ant level.
• Check belt tension regularly.
• Every week - during winter months or other periods
when the system is not being operated regularly- run
the system, set for maximum cooling, for 10 or 15
minutes to insure proper lubrication of seals and
moving parts.
INSTALLING GAUGE SET TO CHECK
SYSTEM OPERATION
Compressor Suction and Discharge Connector
Compressor connector assemblies used on all vehicles
are of the same basic design consisting of the inlet
(suction) and outlet (discharge) connections, gauge fittings
and muffler and, in general, the assemblies differ only in
the location of the gauge fittings.
On Universal and Four-Season Systems the outlet line
extends along side of and toward the front of the com-
pressor and the muffler in the line is bracket mounted to
the compressor body. In all Universal Systems the gauge
fittings for both low and high pressure sides of the sys-
tem are located in the connector body. On Four-Season
Systems the high pressure gauge fitting is located on the
muffler and the low pressure gauge fitting is on the POA
Valve.
The Chevy n All-Weather System compressor con-
nector assembly is similar to the Universal System
connector assembly described above except that the
muffler extends straight out from the connector and
is not bracket mounted to the compressor.
Universal and Chevy II All-Weather System
1.
Install Gauge Adapter (J-5420 or J-9459) onto the
high and low pressure hoses of the gauge set.
2.
With the engine stopped, remove the caps from the
cored valve gauge, connectors on the compressor
fittings block.
3.
Connect the gauge lines with adapters to the threaded
connectors on the compressor fittings block.
Four-Season and Comfortron Systems
Installation of the gauge set onto the Four-Season and
Comfortron systems is accomplished in the same manner
as outlined above except that system performance checks
must be performed with the low pressure hose line and
adapter attached to the fitting on the POA valve. Charging
procedures should be performed with the high pressure
gauge line connected to the high pressure gauge fitting
located on the outlet line muffler and the low pressure
gauge line attached to the POA fitting.
CAUTION: When removing gauge lines from
the compressor fittings block be sure to remove
the adapters from the fittings rather than the
gauge lines from the adapters.
PERFORMANCE TEST
This test may be conducted to determine if the system
is performing in a satisfactory manner and should be
used as a guide by the serviceman in diagnosing trouble
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-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-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
HEATER AND AIR CONDITIONING 1A-76
Fig.
112—-Heater Core Removal—Four-Season System (Corvette)
3.
Replace the core case into the car as described
under Heater and Air Distributor Assembly.
COMPRESSOR
The same basic six.cylinder reciprocating compressor
is used in all systems.
Two variations of the basic compressor are used. One,
with a displacement of 12.6 cu. in. is used with the Four-
Season System. The second model, having displacement
of 10.8 cu. in. is used with the Universal and All-Weather
Systems.
AH Systems
Removal
1.
Purge the refrigerant from the system.
2.
Remove connector attaching bolt and connector. Seal
connector outlets.
3.
Disconnect electrical lead to clutch actuating coil.
4.
Loosen brace and pivot bolts and detach belt.
5. Remove the nuts and bolts attaching the compressor
brackets to the mounting bracket.
6. Before beginning any compressor disassembly, drain
and measure oil in the compressor. Check for
evidence of contamination to ..determine if remainder
of system requires servicing. Compressor Servicing
information is located in the Chassis Overhaul
Manual.
Installation
1.
li oil previously drained from the compressor upon
removal shows no evidence of contamination, replace
a like amount of fresh refrigeration oil into the com-
pressor before reinstallatLon. If it was necessary to
service the entire system because of excessive con-
tamination in the oil removed, install a full charge of
"fresh refrigeration oil in the compressor. (See
Checking Compressor Oil Charge under Checking
Oil)
2.
Position compressor on the mounting bracket and
install all nuts, bolts and lock washers.
3.
Install the connector assembly to the compressor
rear head, using new "O" rings.
4.
Connect the electrical lead to the coil and install
and adjust compressor belt.
5. Evacuate and charge the system.
6. Leak test the system and check for proper operation.
Fig.
113—Heater Hoses^-Four-Season System (Corvette)
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-31
Fig.
77—Differential Pinion Shaft Removal
AXLE SHAFT
Removal
1.
Raise vehicle to desired working height and remove
wheel and tire assembly and brake drum.
2.
Clean all dirt from area of carrier cover. *
3.
Drain lubricant from carrier by removing cover.
4.
Remove the differential pinion shaft lock screw and
the differential pinion shaft (fig. 77).
5. Push flanged end of axle shaft toward center of
vehicle and remove "C" lock from button end of
shaft.
6. Remove axle shaft from housing, being careful not
to damage oil seal.
Wheel Bolt Replacement .
Press bolts out of axle shaft flange (as illustrated in
Figure 78) and press new bolts into place, making sure
that they are tight and square with flange.
Off Seal and/or Bearing Replacement
•1.
Remove the oil seal by using the button end of the
axle shaft - insert the button end of the shaft behind
the steel case of the oil seal, then pry seal out of
bore being careful not to damage housing.
2.
Insert Tool J-8119 into bore and position it behind
bearing so that tangs on tool engage bearing outer
x race. Remove bearing, using slide hammer as shown
in Figure 79. Figure 80 shows a detail of axle
housing outer end.
3.
Lubricate new bearing with wheel bearing lubricant,
and install bearing so that it bottoms against
Fig.
79—Wheel Bearing Removal
shoulder (fig. 81). To install bearing use Tool
J-21491 for the Chevelle, Camaro and Chevy JI
light-duty axle and Tool J-21051 for all Chevrolet
models and also for Chevelle, Camaro and Chevy tl
models with heavy-duty axle.
Pack cavity between the seal lips with a high melting
point wheel bearing lubricant; position seal on tool
(Use J-21491 for the Chevelle, Camaro and Chevy II
light-duty axle and J-21051 for all Chevrolet models
and also for Chevelle, Camaro and Chevy II models
with heavy-duty axle) and position seal in axle
housing bore, tap seal into place so that it bottoms
against bearing (fig. 81).
Brake Flange Plate Replacement
1.
Remove "brake line at wheel cylinder inlet and dis-
assemble brake components from flange plate. Refer
to Section 5 for brake disassembly procedure.
2.
Remove 4 nuts securing flange plate to axle housing.
3.
Install new flange plate to axle housing and torque
nuts to specifications.
Fig.
78—Wheel Bolt Replacement
Fig.
80-Axle Housing Detail
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-36
Fig.
94—Installing Pinion Oil Seal
DIFFERENTIAL CARRIER
Removal
1.
Disconnect spring end link bolts as outlined in
Spring—Removal, in this section.
2.
Disconnect axle drive shafts at carrier by removing
"U"
bolts securing trunnion to side gear yoke.
3.
Disconnect carrier front support bracket at frame
crossmember.
4.
Disconnect propeller shaft at transmission and at
companion flange. Slide transmission yoke forward
into transmission. Drop propeller shaft down and
Fig.
95-Pinion Sea! Installed
out toward the rear.
5. Mark camber cam and bolt relative location on strut
rod bracket and loosen cam bolts.
6. Remove four bolts securing bracket to carrier lower
surface and drop bracket. Remove camber cam bolts
and swing strut rods up and out of the way.
7. Remove eight carrier-to-cover bolts. Loosen bolts
gradually to allow lubricant to drain out.
8. With mounting bolts removed, pull carrier partially
out of cover, drop nose to clear crossmember and
gradually work carrier down and out.
Installation
1.
Clean inside of carrier cover and liberally grease
gasket surface. Place new gasket on cover.
2.
Cut heads off two l/2"-13 x 1-1/4" bolts and slot
unthreaded end. Install these aligning studs into two
below-center carrier bolt holes, one on each side.
3.
Raise carrier into position aligning studs into
cover (fig. 96).
4.
Install carrier-to-cover bolts and tighten securely.
5. Connect propeller shaft to companion flange and
transmission yoke.
6. Install rubber cushion on bracket and position to
frame crossmember. Install hut and torque to
specifications.
7. Raise axle drive shafts into position and assemble
inboard trunnion to side gear yokes with "U" bolts.
8. Assemble strut rods to bracket and raise bracket
into position under carrier. Install four bolts and
torque to specifications. Move camber cams to
marked location and tighten cam nuts.
Fig.
96—Installing Carrier Assembly
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE 6-13
Fig.
1L- In
Line Engines (Typical)
NOTE:
If plug for propeller shaft open-
ing in transmission is not available, drain
transmission.
10.
11.
12.
Disconnect:
• Shift linkage at transmission.
• Speedometer cable at transmission.
On synchromesh equipped vehicles, disconnect clutch
linkage at cross-shaft then remove cross-shaft en-
gine bracket.
Remove rocker arm cover as outlined, then attach
engine lifting adapter at the proper cylinder head
bolt locations.
13.
Remove front mount through bolts.
14.
Attach lifting device and raise engine to take weight
off front mounts, then remove rear mount bolts.
15.
Raise engine to take weight off rear mount, then
remove crossmember.
NOTE:
On Chevrolet vehicles it will be neces-
sary to remove mount from transmission before
crossmember can be removed.
NOTE:
On Camaro vehicles it will be neces-
sary to remove mount from transmission and
loosen rear frame cushion bolts before cross-
member can be removed.
16.
Remove engine-transmission assembly from vehicle
as a unit.
17.
Remove transmission (and clutch):
Synchromesh Transmission
a. Remove clutch housing cover plate screws.
b.
Remove bolts attaching the clutch housing to en-
gine block then remove transmission and clutch
housing as a unit.
NOTE:
Support the transmission, as the last
mounting bolt is removed, and as it is being
pulled away from the engine (to prevent damage
to clutch disc).
c. Remove starter and clutch housing rear cover.
d. Loosen clutch mounting bolts a turn at a time (to
prevent distortion of clutch cover) until the spring
pressure is released. Remove all bolts, clutch
disc and pressure plate assembly.
Automatic Transmission
SL.
Lower engine, secured by the hoist, and support
engine on blocks.
b.
Remove starter and converter housing underpan.
c. Remove flywheel-to-converter attaching bolts.
d. Support transmission on blocks.
e. Remove transmission-to-engine mounting bolts.
f. With the hoist attached, remove blocks from the
engine only and slowly guide the engine from the
transmission.
18.
Mount engine in stand.
Installation
1.
Attach lifting device to engine and remove engine
from engine stand.
2.
Install transmission (and clutch):
Synchromesh Transmission
a. Install the clutch on flywheel as outlined in Sec-
tion 7.
b.
Install clutch housing rear cover and starter.
c. Install transmission and clutch housing as out-
lined in Section 7.
d. Install clutch housing cover screws and tighten
securely.
Automatic Transmission
a. Position engine adjacent to the transmission and
align the converter with the flywheel.
CHEVROLET CHASSIS SERVICE MANUAL