Chevrolet 10 1971 Series, Chassis Service Manual

Page: 57 / 466

HEATER AND AIR CONDITIONING 1A-39
2. Install the switch electrical connections as noted in
Figure 55. If the thermostatic switch was removed,
be sure to install the sensing capillary in the bracket
as shown in Figure 57.
3. Reverse Steps 1-7 of the "Removal" procedures, be­
ing careful not to pinch or otherwise damage the
capillary when installing the duct and cover assem­
blies.
EVAPORATOR CORE, EXP A N SIO N VALVE,
BLOWER M O TO R A N D WHEELS
To gain access to these components, it is necessary to
disconnect the refrigerant lines and remove the entire
blower-evaporator unit from the vehicle.
Removal
1. Disconnect the battery ground cable.
2. Purge the system of refrigerant.
3. Remove the glove box and door assemblies.
4. Remove the dash and kick panel attachments.
5. Disconnect the drain tubes at the case.
6. Disconnect the refrigerant lines at the top of the
case. Cap or tape the open connections at once.
7. Lower the entire unit to the floor, being careful not
to damage the wiring harness.
8. Remove the duct rear cover screws and then with a
small screwdriver, carefully unclip the cover.
9. Disconnect the blower motor lead wire. Disconnect
the wiring harness from the switches and remove the
entire blower-evaporator unit from the vehicle.
10. Blower Motor and Wheels (Fig. 58)—Disconnect the
blower ground wire. Remove the lower to upper
case screws and separate the case halves. Remove
the motor clamp screw and remove the clamp.
Loosen the blower wheel set screws and remove the
wheels from the motor shaft.
Expansion Valve (Fig. 58)—Remove the evaporator
core outlet line cover. Remove the expansion valve
capillary bulb clamps. Remove the expansion valve
clamp screw. Disconnect the valve inlet and outlet
lines and remove the expansion valve. Cap or tape
the open connections at once.
Fig. 58— Blower Motor Installation
Evaporator Core (Fig. 58)—Remove the evaporator
core outlet line cover. Remove the expansion valve
capillary bulb clamps. Remove the (4) upper case
to core screws, core outlet line clamp screw and
expansion valve inlet line clamp screw. Remove the
upper case from the core and expansion valve.
Disconnect core at the inlet and outlet line connec­
tions and separate the core and expansion valve. Cap
or tape the open connections at once.
Installation
1. Blower Motor and Wheels—Install the blower wheels
onto the motor shaft as shown in Figure 58. Install
motor and wheels into the lower half of case, placing
the foam rubber mounting strip around the motor.
Install the motor clamp and install the screw. Ro­
tate the blower wheels and determine if interference
exists. Interference can be corrected by moving the
motor slightly in its mount or by changing the wheel
location on the motor shaft. Install the lower case
to the upper case and connect the motor ground wire.
AIR DUCT
BLOWER
SWITCH
THERMO
CAPILLARY INSTALLED
IN BRACKET
THERMOSTATIC
SWITCH
EXPA N SIO N
VALVE
CAPILLARY
EVAPORATOR
EXPA N SIO N
VALVE
Fig. 5 7 — Thermostatic Sw itch C a p illa ry Retaining Bracket
Fig. 5 9 — Evaporate Core and Expansion V a lv e Location
10-30 CHEVROLET TRUCK SERVICE MANUAL