Chevrolet 10 Series 1970, Service Manual

Page: 33 / 671

HEATER AND AIR CONDITIONING 1A-3
TILT CAB HEATER
The tilt cab heater controls a re located on the dash
betw een the steerin g column and radio. The controls
d iffe r fro m the Deluxe A ir H eater in that fou r le v e r s are
used to control heater operation (fig. 4).
AIR Lever
T h is le v e r , through use of a bowden cable, operates the
A i r D oor which controls a irflo w through the system . With
the le v e r fu lly up, no a ir can enter the system . W ith the
le v e r fu lly down, maximum a irflo w is allowed.
HEAT Lever
The H E A T le v e r regulates coolant flo w through the
h ea ter co re v ia a th erm ostatic va lve mounted on the core.
W ith the le v e r fu lly up, no coolant flow s through the
h ea ter co re. W ith the le v e r fu lly down, maximum coolant
flo w is allow ed, thus creatin g maximum heating. T e m ­
p era tu re can be tem pered by va ryin g the le v e r position.
DEF Lever
The DEF le v e r , through the use of a bowden cable, op­
e ra te s the D e fro s te r Door in the distribu tor duct. When
fu lly up, all a irflo w is d irected out the flo o r outlets. M ov­
F ig . 4 —T ilt C ab H e ater C o n tro l Panel
ing the le v e r downward, channels p artial o r fu ll a irflo w to
the d e fro s te r outlets.
FAN Lever
When fu lly up, the fan is inoperative. M oving the le v e r
downward operates the th ree-sp eed fan.
COMPONENT REPLACEMENT AND REPAIR
BLOWER ASSEMBLY
1 0 -6 0 Series (Exc. Tilt C ab)
Removal
1. Disconnect battery ground cable.
2. (10-30 S e rie s ) Support the righ t fron t of the hood in
the fu lly ra ised position.
3. (10-30 S e rie s ) C a refu lly s c rib e the hood and fender
locations of the righ t hood hinge and rem ove the
hinge.
4. Unclip the b low er w ire at the b low er flange term in al
and note o r m ark the m otor flange position in r e la ­
tion to the b lo w er case.
5. R em ove the blow er assem bly mounting screw s.
6. R em ove the blow er assem bly (pry the flange away
fro m the case ca refu lly i f the s e a le r acts as an ad­
h esive).
(40-60 S e rie s --tu rn the m otor until its
flange c le a rs the hood hinge.)
7. R em ove the nut attaching the b lo w er wheel to the
m otor shaft and separate the assem bly.
Installation
1. A ssem b le the b low er wheel to the m otor with the
open end of the b low er away fro m the m otor.
2. In stall the assem bly to the b lo w er case, connect
ground strap, and connect the m otor w ire.
3. (10-30 S e rie s ) Remount the hood hinge aligning it
ca refu lly with the scrib ed lines. Check hood
alignment.
4. Connect battery ground cable.
Tilt Cab
Rem oval
1. Disconnect the b attery ground cable.
2. R o ll the flo o r mat back from the heater m otor area.
3. R em ove the s c re w attaching blow er housing b race to
cowl panel.
4. Rem ove s c re w attaching co re case b race to cowl
panel.
5. Unclip the b low er w ire at the b low er flange term in al
and note o r m ark the m otor flange position in r e ­
lation to the b low er case.
6. R em ove the b low er assem bly mounting screw s.
7. L o w er the b low er assem bly.
L ift upward on the
heater assem bly until the b low er wheel cle a rs the
F ig . 5 — D e lu xe A ir H e ater A ssem bly
CHEVROLET TRUCK SERVICE MANUAL