Muffler And Connector B Lock; Water V A L V - Chevrolet 10 Series 1970 Service Manual

HEATER AND AIR CONDITIONING 1A-40
2. P u rge the system of re frig e ra n t.
3. R em ove the re a r duct as outlined p revio u sly.
4. Disconnect the b low er m otor leads, ground w ire,
th erm ostatic switch and re la y connections and the
therm ostatic sw itch sensing line.
5. D isconnect the r e frig e ra n t lin es at the re a r o f the
b lo w e r-e v a p o ra to r assem bly.
6. Rem ove the b lo w er-e v 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 v a p o ra to r assem bly fa r
enough to disconnect the re s is to r w irin g harness.
R em ove the assem bly and place it on a w ork bench
upside down.
7. Rem ove the lo w er to upper case screw s and rem ove
the lo w e r case assem bly.
and upper case fro m the evap orator core.
8. R em ove the expansion va lve in let and outlet lin es and
cap o r tape the open connections at once. R em ove the
expansion va lve ca p illa ry bulbs fro m the evaporator
outlet line and rem ove the va lves.
9. R em ove the p lastic pins holding the screen to the
co re and rem ove the screen.
Installation
1. In stall the w ire screen to the fron t of the co re and
in s e rt the p la stic pins.
2. In stall the expansion va lv e inlet, outlet and external
lin es using new "O " rin gs coated with clean r e fr ig ­
eration o il. Install the sensing bulbs to the evapora­
to r outlet line as shown in F igu re 54, making sure the
bulbs have good contact with the line.
NOTE:
Add 3 oz. clean r e frig e ra tio n o il when
installin g a new co re.
3. Install the upper case and upper shroud to the core.
In stall the th erm ostatic switch sensing ca p illa ry into
the p la stic clip s at the fron t o f the core.
4. Install the lo w e r co re case and b low er assem blies.
5. Install the b lo w e r-e v a p o ra to r to the ro o f panel, fir s t
connecting the re s is to r w ires.
6. Connect the re frig e ra n t lin es to the b lo w e r-e v a p o ra to r
unit using new " O " rin gs coated with clean r e fr ig e r a ­
tion o il.
7. Connect the blow er lead w ire s , ground strap, th erm o­
static switch and re la y harnesses.
F ig . 5 6 —Compressor C o n n e c to r B lock and M u ffle r
Rem ove the upper shroud
8. Install the re a r duct as outlined p reviou sly.
9. Connect the battery ground cable.
10. Evacuate, charge and perform an ce test the system .
MUFFLER A N D CONNECTOR BLOCK
Removal (Fig. 56)
1. Pu rge the system .
2. Rem ove hoses at the co m p ressor in let and m u ffler
outlet pipes. Cap the connections.
3. Rem ove m u ffler outlet pipe clamp.
4. R em ove bolt retaining connector block to com p ressor
and rem ove the connector and m u ffler assem bly. Cap
the co m p ressor ports i f not im m ed iately remounting
m u ffler assem bly.
Installation
1. A ssem b le the connector block to the co m p ressor
using new "O " ring seals wetted with clean r e fr ig e r a ­
tion o il.
2. Secure the m u ffler outlet pipe in the pipe clamp.
3. Connect the r e frig e ra n t hoses to the com p ressor in ­
let and m u ffler outlet pipes.
4. Evacuate and rech arge the system .
WATER VALVE (Fig. 5 7 )
The w ater va lve is installed in the heater core inlet
lin e. When vacuum is applied to the v a lve, (H E A T L E V E R
A T O F F ) the va lve is closed, preventing coolant flow
through the heater co re.
the va lve, (H E A T L E V E R M OVED T O THE RIGHT OF
O F F ) the valve is open and coolant is allow ed to flow
through the heater c o re .
Replacement
1. Disconnect the battery ground cable.
2. Disconnect the vacuum line at the va lve.
3. P la c e a pan under the veh icle, disconnect the inlet
and outlet hoses and
container.
F ig . 5 7 —W a te r V a lv e
When no vacuum is applied to
drain the coolant into the
CHEVROLET TRUCK SERVICE MANUAL