Buick LeSabre 1965 Service Manual page 811

11 - 7 8 OPTIONAL HEATER-AIR CONDITIONER SYSTEM
ACCESSORIES
2. Main Vacuum Switch Adjust-
ment - Place FAN lever in off
position. Loosen main vacuum
switch attaching screws and push
switch against control lever on
circuit control assembly to fully
depress plunger. Tighten mount-
ing screws. See Figure 11-89.
3. Compressor Clutch Control
Switch A d j u s t m e n t -Loosen
screws securing switch to control
assembly. Place Climate Control
lever in VENT position and push
switch against cam of lever until
it clicks open. Secure in position.
Move lever between NORM and
VENT positions and listen for and
observe both contacts of clutch
control switch opening. Switch
must be fully open by time lever
in VENT position.
e. Adjustments—49000 Series
There is no service adjustment
on the blower switches, the ex-
pansion valve vacuum modulator,
vacuum diaphragms or vacuum
disc switches on 49000 Series
cars.
Adjustments for the control wires
attached to the heater control as-
sembly are the same as for non-
air conditioned cars (ret to par.
11-8 and see Figure 11-42).
f. Suction Throttle Valve
Adjustments
IMPORTANT: The suction throt-
tle valve adjustment is to be made
only after the functional test
shows evaporator pressure sig-
nificantly different from the chart.
1. Have a service gauge set con-
nected to Schrader valves as
shown in Figure 11-153.
2. Set controls for maximum
cooling, heater off, ventilators
closed and all air conditioner out-
lets open.
(a) On 45000, 46000 and 48000 Se-
ries the climate control is set at
REC, the WARMER lever fully
left and the FAN on HI.
(b) On 49000 Series the Air Con-
ditioned Air Control, Temperature
Control, and Fan switch levers
are set full on. Heater Temp and
Defroster levers are set to OFF.
3. Engine set at 2000 RPM.
4. Remove the vacuum hose from
the 49000 suction throttle vacuum
diaphragm. Do not remove hose
from the 45000, 46000 and 48000
diaphragm.
5. Three minutes after the valve
has started to control, check the
gauge readings and outlet temper-
ature against the functional test
chart.
6. If necessary to adjust STV,
loosen the large lock nut on
sleeve of suction throttle valve
vacuum diaphragm.
7. To adjust valve, rotate dia-
phragm assembly clockwise to in-
crease evaporator pressure and
counterclockwise to d e c r e a s e
pressure.
8. After adjusting the valve, ob-
serve operation of the system for
a few minutes to check readings.
9. Tighten lock nut on sleeve and
reinstall the vacuum hose on the
49000 vacuum diaphragm.
10. Check operation of suction
throttle valve.
(a) On 45000, 46000 and 48000 Se-
ries, move the WARMER lever a
short distance forward from the
off position. There should be no
vacuum to the vacuum diaphragm
of the valve.
With the WARMER lever in this
position, the evaporator pressure
should raise by approximately
three psi. If the evaporator pres-
sure does not increase, check the
water valve and STV vacuum disc
switch, improper vacuum hose
connections or kinked vacuum
hoses. If these are correct, the
suction throttle valve is defective
and should be repaired.
(b) On 49000 Series, move the Air
Conditioner Air Control lever to
normal position and the temper-
ature c o n t r o l and Fan switch
levers to Low.
With the levers in this position,
the evaporator should raise to
approximately 50 psi. Return the
levers to full on and recheck set-
ting of the suction throttle valve
If the 49000 evaporator pressure
does not increase when Air Con-
ditioning Temperature Control and
Fan lever are at Low, check op-
eration of vacuum modulator by
connecting a vacuum gauge to the
hose that goes to the STV. The
modulator should regulate mani-
fold vacuum from 6 to 7 inches
when the temperature control
lever is moved from the Low po-
sition to 0 inches when the tem-
perature control and Fan switch
levers are respectively in the
cooler and high position. If mod-
ulator does not function properly,
check vacuum hose connections,
check for kinked hose or for de-
fective modulator.
g. Removal and Installation
of Suction Throttle Valve
1. D i s c h a r g e refrigerant from
system as described in subpara-
graph " c ' \
2. Disconnect lines from valve.
3. Remove valve mounting screws
and remove valve.
NOTE: All of the openings to the
air conditioning system should be
capped or plugged during the time
the STV is removed.
4. Install valve by reversing pro-
cedure for removal, paying atten
r
tion to the following:
(a) Install new "O" rings on line
fittings.
(b) The valve piston must be lu-
bricated with 525 compressor oil