Buick LeSabre 1965 Service Manual page 133

ENGINE FUEL AND EXHAUST
4-BARREL CARTER 3 - 5 7
^ ^ i * CHOKE
mmbr FULLY
I • C L O S E D
1M
1 : BEND HERE
7 3 1 AS REQUIRED
JF
5 5
*
8
j .
5 1 9 7
•P
Cf*FAST IDLE CAM
i & L ^ INDEX MUST ALIGN
**
5
^^WITH CENTER OF
FAST IDLE SCREW
Figure 3-78—Fast Idle Cam Adjustment
lower angle as required to obtain
measurement using Tool J-4552.
Turn throttle stop screw in (from
fully closed throttle position) 3/4
turn which should p r o v i d e an
initial idle adjustment.
4. Adjust Fast Idle Cam Position.
With c h o k e valve held fully
closed, open throttle slightly to
allow fast idle cam to spring to
a neutral position. Now index
mark on fast idle cam must align
with center of fast idle screw. If
mark does not align, bend fast
idle rod using Tool J-5197 as
required to make mark align. See
Figure 3-78.
NOTE: With choke fully closed
and index mark aligned, lug on
fast idle cam must clear stop on
throttle body.
5. Adjust Unloader. Hold throttle
wide open and check clearance
between upper edge of choke valve
and inner wall of air horn using
the 7/32" gauge or a 7/32" drill.
Bend unloader tang on throttle
shaft lever as required to obtain
7 / 3 2 " GAUGE
TO ADJUST, BEND
UNLOADER TANG
HOLD THRO
FULLY OPEN f""8fP
its.
ADJUST BY BENDING
SECONDARY POSITIVE \
CLOSING SHOE J V ^
- 1 PRIMARY POSITIVE
gPfMCLOSINGSHOE
^ ^ - .020" GAUGE
Figure 3-80—Closing Shoe Adjustment
this clearance using pliers. See
Figure 3-79.
6. Adjust Closing Shoe. Hold
choke open and rotate primary
throttle lever through full range.
Check clearance between positive
closing shoes on primary and
secondary throttle l e v e r s at
closest p o s i t i o n using .020"
gauge. Bend secondary closing
shoe as required to obtain this
clearance using pliers. See Fig-
ure 3-80.
7. Adjust Throttle Opening. At
wide open t h r o t t l e , primary
throttle valves should be vertical.
Secondary throttle valves should
be a few degrees from vertical.
Upper edge of secondary valves
should just c o n t a c t auxiliary
valves when both are wide open.
If necessary, bend wide open stop
lug.
Primary and secondary throttle
valves should reach wide open
throttle at the same time. To
synchronize, bend secondary op-
erating rod. See Figure 3-81.
RY
OPERATING
ROD
SECONDARY
THROTTLE LEVER
The pick-up lever located on the
primary throttle shaft has two
points of contact with the loose
lever on the primary shaft. Cau-
tion should be taken that the pick-
up lever contacts the loose lever
at both points at the same time.
See Figure 3-81. If they do not
make this c o n t a c t , bend pick-
up l e v e r to o b t a i n proper
engagement.
8. Adjust S e c o n d a r y Throttle
Lock-Out. Open primary throttle
valves slightly to clear fast idle
cam and manually open and close
choke valve. Lock-out tang on
secondary throttle should freely
engage in notch of lock-out dog
while barely missing edge of
notch. If n e c e s s a r y to adjust,
bend tang on secondary throttle
lever using Tool J-6058-A. See
Figure 3-82.
Install carburetor on car. Make
final idle speed and mixture ad-
justments on car in normal man-
ner. See paragraph 3-8.
9
* Adjust Fast Idle. Make adjust-
ment on car with engine operating
at normal temperature and trans-
mission in drive as follows:
(a) Position fast idle cam so that
fast idle screw is resting on low
step of fast idle cam with edge
of screw aligned with starting
edge of cam.
(b) Adjust fast idle screw so that
engine runs 600 RPM.
LOCK-OUT
ARM
Figure 3-79—Unloader Adjustment
Figure 3-81—Secondary Throttle
Opening Adjustment
Figure 3-82—Secondary Throttle
Lock-Out Adjustment