Evaporator Core; Blower Motor Switch - Chevrolet 1980 Light Duty Truck Service Manual

EVAPORATOR
OUTLET LINE
Fig. 1 B-38-Blower-Evaporator (C-K Overhead System)
7. Disconnect the valve inlet and outlet lines and
remove the expansion valve assembly. Cap or plug the open
connections at once.
Installation
1. Remove caps or plugs from system connections and
install the new valve assembly using new "O" rings coated
with clean refrigeration oil.
2. Install the sensing bulb, making sure that the bulb
makes good contact with the core outlet line.
3. Install the lower case and blower motor assemblies.
Connect the blower motor lead and ground wires.
4. Install the rear duct as outlined previously.
5. Connect the battery ground cable.
6. Evacuate, charge and check the system.
EVAPORATOR CORE (Fig. 1 B-40)
Removal
1. Disconnect the battery ground cable.
2. Purge the system or refrigerant.
3. Remove the rear duct as outlined previously.
Fig. 1 B -3 9~ B lo w er M otor (C-K O verhead System)
EVAPORATOR
LEAD WIRE
INLET LINE
EVAPORATOR
AIR C O N D ITIO N IN G
EVAPORATOR
SCREEN
EXPANSION EVAPORATOR
VALVE CORE
Fig. 1 B-40-Expansion Valve C69 System
4. Disconnect the blower motor lead and ground wire
connections.
5. Disconnect the refrigerant lines at the rear of the
blower-evaporator assembly. Cap or plug the open
connections at once.
6. Remove the blower-evaporator support to roof rail
screws, lower the blower-evaporator assembly and place it
on a work bench upside down.
7. Remove the lower to upper case screws and remove
the lower case assembly. Remove the support to upper case
screws and remove the upper case from the evaporator core.
8. Remove the expansion valve inlet and outlet lines
and cap or plug the open connections at once. Remove the
expansion valve capillary bulb from the evaporator outlet
line and remove the valve.
9. Remove the plastic pins holding the screen to the
core and remove the screen.
Installation
1. Install the wire screen to the front of the core and
insert the plastic pins.
2. Install the expansion valve inlet and outlet lines
using new "O" rings coated with clean refrigeration oil.
Install the sensing bulb to the evaporator outlet line as
shown in Figure IB-44; make sure the bulb has good contact
with the line.
Add 3 oz. clean refrigeration oil when installing a new
core.
3. Install the upper case and supports to the core.
4. Install the lower core case and blower assembly.
5. Install the blower-evaporator assembly to the roof
and install the support to roof rail screws.
6. Connect the refrigerant lines to the blower-
evaporator unit using new "O" rings coated with clean
refrigeration oil.
7. Connect the blower lead and ground wires.
8. Install the rear duct as outlined previously.
9. Connect the battery ground cable.
10. Evacuate, charge and check the system.
BLOWER M O TO R S W ITC H
The three-speed (LO-MED-HI) blower motor switch
is located in the instrument panel, just to the left of the ash
tray (fig. IB-41).
1B-41
BLOWER-EVAPORATOR
UPPER CASE
SENSING BULB
LIG H T T R U C K S E R V IC E M ANUAL