l. Insert a 5/16-inch rod through the shaft hole and lightly tap out the shaft hole plug (37).
NOTE
If the throttle shaft bushings (33) must be replaced, remove them one at a time and
ream as instructed below.
Insert a 3/8-inch fine thread tap into one of the bushings (33). Drive out the bushing from the opposite side with a 5/16-
inch rod. Install a new bushing (33) with the special bushing driver (par. 179). Insert the special reamer (par. 179)
through the old bushing and ream the new bushing to size. Repeat this operation to install a new bushing on the opposite
side.
m. Drill a No. 46 hole in the center of the bowl channel plug (21). Screw the special plug extractor (par. 179) into the
hole counterclockwise until firmly seated. Strike sharply on the opposite end to remove the plug. Repeat the above
operation to remove the second bowl channel plug (46).
186. Carburetor Cleaning and Inspection
a. Clean all metal parts thoroughly with a cleaning solvent and blow them dry with compressed air. Blow out all
passages (channels) in the air intake, fuel bowl, and throttle body. Make certain that all carbon deposits have been
removed from the blower and the idle ports. It is advisable to reduce the flow of compressed air in each channel to insure
the removal of all particles of dirt. Never use a wire or a drill to clean out a jet or channel.
b. Inspect the machined surface of the air intake body for dents, warpage, or any other damage that might cause air
leaks which would upset the fuel delivery characteristics of the carburetor. Replace the air intake body if such damage is
evident.
c. Examine the fuel bowl to make certain that the secondary venturi is not loose and to insure that gasket surfaces
have not been damaged to the part where air leaks might result.
d. Several carburetor parts should be automatically replaced at every overhaul period. These parts are all gaskets
and fiber washers, the fuel valve and seat (19), the pump (49), the choke plate spring (8), and the check valve (18).
e. Examine the float parts carefully for damage. The float must be replaced if loaded with gasoline, dented, or if the
float axle bearing is excessively worn. Replace the axle if wear can be detected visually on bearing surface.
f.
Inspect the point of the idle adjusting needle (34). It must be smooth and free of ridges. If damaged, the idle
adjusting needle must be replaced.
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