Craftsman 917.272420 - Manual (Page 28)

TO ADJUST CARBURETOR
The carburetor has been preset at the factory
and adjustment should not be necessary.
However, minor adjustment may be required
to compensate for differences in fuel,
temperature, altitude or load. If the carburetor
does need adjustment, proceed as follows;
In general, turning the adjusting needles
in
(clockwise) decreases the supply of fuel to
the engine giving a leaner fuel/air mixture.
Turning the adjusting needles
out (counter­
clockwise) increases the supply of fuel to the
engine giving a richer fuel/air mixture.
IMTORTAMT: Damage to the needles and
seats in carburetor may result if turned in too
tight.
NOTE: The carburetor on this engine is low
emission. It is equipped with an idle fuel
adjusting needle with a limiter cap, which
aliows some adjustment within the limits
allowed by the cap. Do not attempt to remove
the limiter c^. The limiter cap cannot be
removed without breaking the adjusting
needle.
1 .
2 .
4.
ACCELERATION TEST-
6. Move throttle control lever from stow to
fast position. If engine hesitates or dies,
turn idle fuel adjusting needle
out
(counterclockwise) 1/8 turn. Repeat test
and continue to adjust, if necessary, until
engine accelerates smoothly.
High speed stop is factory adjusted. Do
not adjust - damage may result.
IMPORTANT: Never tamper with the
engine governor, which is factory set for
proper engine speed. Overspeeding the
engine above the factory high speed
setting can be dangerous. If you think the
engine-governed high speed needs
adjusting, contact a Sears or other
qualified service center, which has prope
equipment and experience to make any
necessary adjustments.
Idle Speed
5.
Be sure you have a clean air filter and the
throttle control cable is adjusted properly
(see above).
Start engine and allow to warm for five
minutes. Make adjustments vwth engine
running and shift/motion control lever in
neutral (N) position.
Idle speed setting - With throttle control
lever in stow position, engine should idle
at 1750 RPM. if engine idles too slow or
fast, turn idle speed adjusting screw in or
out until correct idle is attained.
idle fuel needle setting - With throttie
control lever in stow position, turn idle fuel
adjustment needle
in (cloctwvise) until
engine begins to die and then turn out
(counterclockwise) until engine mns
rough. Turn needle to a point midway
between those two positions.
Recheck idie speed. Readjust if neces­
sary.
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