GMC 1976 ZEO 6083 Maintenance Manual page 360

6M- 1 8
ENGINE FUEL SYSTEM
Figure 22-Fuel Filter
THROTTLE BODY DISASSEMBLY
1 . Remove pump rod from throttle lever.
2. DO NOT REMOVE idle mixture limiter caps,
unless it is necessary to replace the mixture needles
or normal soaking and air pressure fails to clean the
idle passages . If the idle mixture needles are
removed, adjustment procedures will be covered in
the "Carburetor Adjustment" chart. If necessary to
remove the idle mixture needle, destroy plastic li-
miter cap. Do not install a replacement cap as a bare
mixture screw is sufficient to indicate that the mix-
ture has been readjusted .
CLEANING AND INSPECTION
1 . Thoroughly clean carburetor castings and
metal parts in an approved carburetor cleaner.
Figure 23-Throttle Body Attaching Screws
Figure 24-Throttle Body Gasket
CAUTION:
Rubber parts, plastic parts, and
pump plungers should not be immersed in
carburetor cleaner. However, the delrin
cam on the air valve shaft and the throttle
valve shafts will withstand normal cleaning
in carburetor cleaner.
2. Blow out all passages in castings with com-
pressed air.
CAUTION:
Do not pass drills through jets or
passages.
3. Examine float needle and seat for wear . Re-
place if necessary with float needle assembly .
4. Inspect upper and lower surfaces of carburetor
castings for damage .
5. Inspect holes in levers for excessive wear or out
of round conditions . If worn, levers should be re-
placed .
6. Examine fast idle cam for wear or damage .
7 . Check air valve for binding conditions . If air
valve is damaged air horn assembly must be re-
placed .
8 . Check all throttle levers and valves for binds
or other damage .
THROTTLE BODY
1 . If removed, install idle mixture needles and