Craftsman 917.272410 - Manual (Page 26)

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
(counterclockwise) increases the supply
of fuel to the engine giving a richer fuel/
air mixture,
IMPORTANT: 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 allows some adjustment within the
limits allowed by the cap. Do not attempt
to remove the limiter cap. The limiter cap
cannot be removed without breaking the
adjusting needle.
1. Be sure you have a clean air filter and
the throttle control cable is adjusted
properly (see above).
2. Start engine and allow to warm for five
minutes. Make adjustments with
engine running and shift/motion
control lever in neutral (N) position.
3. Idle speed setting - With throttle
control lever in slow position, engine
should idle at 1750 RPM. If engine
idles too slow or fast, turn idle speed
adjusting screw in or out unfit correct
idle is attained.
4. Idle-fuel needle setting - With throttle
control lever in slow position, turn idle
fuel adjustment needle
in (clockwise)
until engine begins to die and then
turn
out (counterclockwise) until
engine runs rough. Turn needle to a
point midway between those two
positions.
5. Recheck idle speed. Readjust if
necessary.
ACCELERATION TEST-
6. 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
equipment and experience to make any
necessary adjustments.
Idle Speed
Adjustini
Screw
Idle Fuel
Adjusting
Needle
26