Craftsman 917.275280 - Manual (Page 28)

4. Reassemble air cleaner.
TO ADJUST CARBURETOR .
The carburetor has been present 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
(counterclockwise) increases the supply
of fuel to the engine giving a richer fuel/
air mixture.
IMPORTANT: Damage to the needles
and the seats in carburetor may result if
screw is turned in too tight.
PRELIMINARY SETTING-
1. Be sure you have a clean air filter, and
the throttle control cable is adjusted
properly (see “TO ADJUST
THROTTLE CONTROL CABLE” in the
Service and Adjustments section of
this manual).
With engine off turn idle fuel adjusting
needle in (clockwise) closing it finger
tight and then turn out (counterclock­
wise) 1 turn.
2 .
1. Start engine and allow to warm for five
minutes. Make final adjustments with
engine running and shift/motion
control lever in neutral (N) position.
NOTE: The high idle is set at the factory
and cannot be adjusted.
2. Idle speed setting - With throttle
control lever in slow position, engine
should idle at 1200 RPM. If engine
idles too slow or fast, turn idle speed
adjusting screw in or out until correct
idle is attained.
3. Idle fuel needle setting - With throttle
control lever in slow position, turn idle
fuel adjusting needle In (clockwise)
until engine speed decreases and
then turn out (counterclockwise)
approximately 3/4 turn to obtain the
best low speed performance.
4. Recheck idle speed. Readjust if
necessary.
ACCELERATION TEST-
5. Move throttle control lever from slow 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 proper equip­
ment and experience to make any
necessary adjustments.
FINAL SETTING-
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