Expansion V A L V; Evaporator C O R - Chevrolet 10 Series 1970 Service Manual

5. In stall the center ground
b lo w er lead w ires.
6. Install the re a r duct assem bly as d escribed p r e ­
viou sly.
7. Connect the battery ground cable.
EXPA N SIO N VALVE
Th is system in corp orates two expansion v a lves.
va lv e s do not use the extern al e q u a lizer line (fig . 54).
Removal (Inner V a lv e )
1. D isconnect the battery ground cable.
2. P u rge the system o f re frig e ra n t.
3. R em ove the re a r duct as outlined p reviou sly.
4. D isconnect the center ground w ire and the blow er
m otor lead w ire s . Rem ove the lo w e r to upper case
s c rew s and lo w e r the low er case and b low er m otor
assem b lies.
C A U TIO N : B e fo re
s cre w s , support the case to preven t damage to
the case o r m otor assem b lies.
5. D isconnect the valve sensing bulb fro m the co re out­
let line. See F igu re 54.
6. Disconnect the core inlet and outlet lin es and rem ove
the valve assem bly.
tions at once.
Installation (Inner V a lv e )
1. R em ove caps o r tape fro m system connections and
in stall the new valve assem bly using new "O " rings
coated with clean re fr ig e r a tio n o il.
2. Install the sensing bulb, making sure that the bulb
makes good contact with the co re outlet line.
3. Install the lo w e r case and b lo w er m otor assem blies.
4. Install the r e a r duct as outlined p reviou sly.
5. Connect the battery ground cable.
6. Evacuate, charge and p erform a n ce test the system .
F ig . 54— Expansion V a lv e C a p illa r y Bulbs
w ire s and connect the
These
rem ovin g the low er case
Cap o r tape the open connec­
HEATER AND AIR CONDITIONING 1A-39
Removal (O uter V a lv e )
1. Disconnect the battery ground cable.
2.
Pu rge the system o f re frig era n t.
3. Rem ove the r e a r duct as outlined p reviou sly.
4. Disconnect the blow er m otor ground straps and leads,
re la y and therm ostatic switch w irin g harness.
5. Disconnect the re frig e ra n t lin es at the re a r of the
b lo w er-e v a p o ra to r assem bly.
6. Rem ove the b lo w er-ev a p o ra to r to ro o f panel, attach­
ments and lo w e r the b lo w e r-e va p o ra to r assem bly fa r
enough to disconnect the r e s is to r w irin g harness.
R em ove the assem bly and place on a w ork bench
upside down.
7. Rem ove the lo w e r to upper case screw s and rem ove
the lo w er case assem bly.
fro m the upper case and then rem ove the upper case
fro m the co re.
8. Rem ove the expansion valve bulb fro m the evap orator
outlet lin e. Rem ove the expansion va lve inlet and
outlet lines and cap o r tape the open connections at
once. Rem ove the valve.
Installation (O uter V a lv e )
1. Rem ove the caps o r tape fr o m the r e frig e ra n t con­
nections and in sta ll the new va lve using new "O"
rin gs coated with clean r e frig e ra tio n o il.
2. Install the upper case to the c o re making sure the
sealing strip s a re positioned c o r r e c tly .
upper shroud on the upper case.
3. Install the lo w e r case and b low er a ssem b lies.
4. Install the b lo w er-ev a p o ra to r to the ro o f panel, fir s t
connecting the r e s is to r w ires.
5. Connect the r e frig e ra n t lin es at the re a r o f the
b lo w e r-e va p o ra to r unit using new "O " rings coated
with clean r e fr ig e r a tio n oil.
6. Connect the b low er lead w ire s and ground straps,
therm ostatic sw itch and r e la y harnesses.
7. Install the re a r duct as d escrib ed p reviou sly.
8. Connect the battery ground cable.
9. Evacuate, charge and p erform an ce test the system .
EVAPORATOR CORE (Fig. 55)
Removal
1. Disconnect the b attery ground cable.
F ig . 5 5 — E vapo rato r C ore In s ta lla tio n
Rem ove the upper shroud
In stall the
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