Craftsman 917.270831 - Manual (Page 26)

Choke Closed
Casing
Clamp
Screw
Choke Lever
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 mixture screw in
(clockwise) decreases the supply of fuel
to the engine giving a leaner fuel/air
mixture. Turning the mixture screw 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 reslut if
screw is turned in too tight.
PRELIMINARY SETTING -
• Be sure you have a clean air filter, and
the throttle control cable and choke
are adjusted property (see above).
• With engine off turn idle mixture screw
in (clockwise) closing it finger tight and
then turn out (counterclockwise) 1-1/4
to 1-1/2 turns.
FINAL SETTING-
• Start engine and allow to warm for five
minutes. Make final adjustments with
engine running and siiift/ motion
control lever in neutral (N) position.
• With throttle control lever in slow
position, hold throttle lever against idle
speed screw and adjust idle speed
screw to obtain 1200 to 1400 RPM.
• While still holding throttle lever against
idle speed screw, turn idle mixture
screw in (clockwise) until engine
begins to die and then turn out
(counterclockwise) until engine runs
rough. Turn screw to a point midway
between those two positions.
• Continue to hold throttle lever against
idle speed screw and adjust idle
speed screw to obtain 900 to 1200
RPM. Release throttle lever.
ACCELERATION TEST -
• Move throttle control lever from slow to
fast position. If engine hesitates or
dies, turn idle mixture screw out
(counterclockwise) 1/8 turn. Repeat
test and continue to adjust, if neces­
sary, 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 your nearest AUTHO­
RIZED service center/department, which
has proper equipment and experience to
make any necessary adjustments.
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