Buick LeSabre 1965 Service Manual page 112

3 - 3 6 2-BARREL ROCHESTER
ENGINE FUEL A N D EXHAUST
NOTE: If heavy staking is en-
countered, remove staking from
around power piston retaining
washer.
3. Remove retainer on the end of
pump plunger shaft, then remove
pump assembly from pump inner
arm. Remove pump lever and
shaft assembly by loosening set
screw on inner arm and remov-
ing outer lever and shaft.
4. Remove air horn gasket.
5. Remove two choke valve re-
taining screws, then remove
choke valve from choke shaft.
Remove choke shaft from air
horn, then choke lever and collar
assembly can be removed from
choke shaft.
Note position of the choke lever
in relation to the choke trip lever
on the end of the choke shaft for
ease in reassembly.
c. Disassembly of Float Bowl
1. Remove pump plunger return
spring from pump well. Remove
small aluminum check ball from
the bottom of pump well by in-
verting bowl and shaking into
hand. Remove pump inlet screen
from bottom of fuel bowl.
2. Remove main metering jets.
3. Remove power valve and fibre
gasket.
4. Remove three venturi cluster
attaching screws and remove
cluster and gasket. Center clus-
ter screw has smooth shank and
fibre gasket for the accelerator
pump fuel by-pass and sealing.
5. Using a pair of long nosed
pliers, remove pump discharge
ball spring "T" shaped retainer.
Then remove pump discharge
spring and steel discharge ball.
6. Remove two main well inserts
in the main well.
7. Invert carburetor and remove
three throttle body to bowl at-
taching screws. Remove throttle
body and throttle body to bowl
gasket.
d. Disassembly of
Throttle Body
1. Remove idle mixture adjusting
needles and springs.
No further disassembly of the
t h r o t t l e body is needed. The
throttle valves should never be
removed as the idle and spark
holes are drilled in direct rela-
tion to the location of the throttle
valves and shaft. Removal of the
throttle valves will upset this lo-
cation. The throttle body assem-
bly is only serviced as a complete
unit with throttle valves intact.
e. Cleaning and Inspection
Dirt, gum, water or carbon con-
tamination in or on the exterior
moving parts of a carburetor are
often responsible for unsatisfac-
tory performance. For this rea-
son, efficient carburetion depends
upon careful cleaning and inspec-
tion while servicing.
1. Thoroughly clean carburetor
castings and metal parts in car-
buretor cleaning solvent.
CAUTION: Pump plunger or any
fiber or rubber parts should never
be immersed in carburetor clean-
er. Wash pump plunger in clean
solvent.
2. Blow out all passages in the
castings with compressed air and
blow off all parts until they are
dry. Make sure all jets and pas-
sages are clean. Do not use wires
for cleaning fuel passages or air
bleeds.
3. Check all parts for wear. If
wear is noted, defective parts
must be replaced. Note especially
the following:
(a) Check float needle and seat
for wear. If wear is noted, the
assembly must be replaced.
(b) Check float hinge pin for wear
and float for dents or distortion.
Check float for fuel leaks by
shaking.
(c) Check throttle and choke shaft
bores for wear and out of round.
(d) Inspect idle mixture adjusting
needles for burrs or grooves.
Such a c o n d i t i o n r e q u i r e s
replacement.
(e) Inspect pump p l u n g e r cup;
replace if damaged, worn, or
hard.
(f) Inspect pump- well in bowl for
wear or scoring.
4. Check filter screens for dirt
or lint. Clean, and if they re-
main plugged, replace.
5. If for any reason, parts have
become loose or damaged in the
cluster casting, the cluster as-
sembly must be replaced.
6. It is recommended that new
gaskets be used whenever the
carburetor i s disassembled or
overhauled.
3 - 1 6 ASSEMBLY OF
ROCHESTER
2-BARREL
CARBURETOR
a. Assembly of Throttle Body
1. Screw idle mixture adjusting
needles and s p r i n g s into the
throttle body until finger tight.
Back out screw one turn as a
preliminary idle adjustment.
CAUTION: Do not f o r c e idle
needle against its seat or damage
may result.
2. Invert float bowl assembly and
place the new throttle body gasket
on bowl. Install throttle body on
bowl using three screws and lock
washers. Tighten securely.
b. Assembly of Float Bowl
1. Drop steel pump discharge
check ball into discharge hole.
Install pump discharge spring and
"T" shaped retainer, staking re-
tainer in place.