To Adjust Carburetor; Preliminary Setting; Final Setting; Acceleration Test - Craftsman 917.271860 Owner's Manual

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).
2. 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 S EI-]-ING -
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. 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. Turn 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 or 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.
_. Idle Speed
Screw
Idle Mixture
Screw
Throttle
Lever
Idle
Speed ._
Screw ""
Throttle
Lever
_le Mixture
Screw
28