Float Bowl Assembly; Throttle Body Disassembly; Carburetor Assembly And Adjustment Procedures; Throltle Body Assembly And Installation - Pontiac Grand Prix Service Manual

ENGINE FUEL 6B-9
throttle body to bowl attaching screws. Throttle body
and insulator gasket may now be removed.
2. Remove idle mixture needle and spring.
NOTE: Due to the close tolerance fit of the throttle valve
in the bore of the throttle body, do not remove the throttle
valve or shafi.
CLEANING AND INSPECTION
The carburetor should be cleaned in a cold immersion
type
cleaner.
.
1. Thoroughly clean carburetor castings and metal
parts in an approved carburetor cleaner such as
carbon-X (X-55) or its equivalent.
CAUTION: Any rubber parts, plastic parts, dia-
phragms, pump plungers, should not be immersed in
carburetor cleaner. However, the air horn which has the
plastic vent valve guide and cranking enrichment valve
will withstand normal cleaning in carburetor cleaner.
Make sure the cleaner is thoroughly removedfiom choke
enrichment valve cavily.
2. Blow out all passages in castings with compressed
air. Do not pass drills through jets or passages.
3. Inspect idle mixture need for damage.
4. Examine float needle and seat assembly for wear.
Install a new factory matched set if worn.
5. Inspect upper and lower casting sealing surfaces for
damage.
6. Inspect holes in levers for excessive wear or out
of-round condition. If levers or rods are worn, they
should be replaced.
7. Examine fast idle cam for excessive wear or damage.
8. Check throttle and choke levers and valves for binds
and other damage.
9. Check all spring for distortion or loss in tension,
replace if necessary.
CARBURETOR ASSEMBLY AND
ADJUSTMENT PROCEDURES
THROlTLE BODY ASSEMBLY AND INSTALLATION
(Fig. 68-16)
1. Install idle mixture needle and spring until lightly
seated. Back out five turns as a preliminary idle
adjustment.
Fig. 68-16 Throttle Body Disassembly
2. Invert float bowl and install new throttle body to
bowl insulator gasket making sure all holes in'gasket
align with holes in float bowl.
3. Install throttle body on bowl gasket so that all holes
in throttle body are aligned with holes in gasket.
4. Install two throttle body to bowl attaching screws.
Tighten evenly and secure19 (12- 15 lb. ft.).
FLOAT BOWL ASSEMBLY (Fig. 68-17)
1. Install fast idle cam to boss on float bowl, attaching
with fast idle cam screw. Tighten securely. Part
number on cam faces outward.
2. Install slow idle adjustment screw, if removed.
3. Install seal into recess in idle compensator cavity in
float bowl, then install idle compensator.
FlST IDLE CAM
ATTAWING SCREW
WOKE UAFWuGM
VACUUU
W N E L
AIR Ol4NNEL
Fig. 6B-17 Float Bowl Assembly