Craftsman 917.271820 - Manual (Page 28)

3. Choke should be closed. If it is not,
loosen casing clamp screw and move
choke cable until choke is completely
closed. Tighten casing clamp screw
securely.
4 Reassemble air cleaner.
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 result if
screw is turned in too tight.
PRELIMINARY SETTING-
1. Be sure you have a clean air filter,
and the throttle control cable and
choke are adjusted properly (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 -
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.
2 .
2. 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.
3. 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. Tum screw to a point midway
between those two positions.
4. 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 -
5. 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 a Sears or other
qualified service center, which has proper
equipment and experience to make any
necessary adjustments.