To Adjust Carburetor; Preliminary Setting; Acceleration Test; Final Setting - Craftsman 917.270773 Owner's Manual

• Remove air cleaner cover, filter and cap
tridge plate to expose carburetor choke
(see =AIR FILTER" in the Customer
Responsibilities section of this manual).
• Choke should be closed, tf it is not,
loosen casing clamp screw and move
choke cable until choke is completely
closed. Tighten casing clamp screw se-
curely.
• Reassemble air cleaner.
ClampScrew_
Quarter _ )
Casing
Clamp
Choke
Lever
TO ADJUST-CARBURETOR
The carburetor has been preset at the fan-
tory and adjustment should not be neces-
sary. 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 (counter-
clockwise) 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 tumed in too tight.
PRELIMINARY SETI'ING -
• 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 tum 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 shift/motion control
lever in neutral (N) position.
• With throttle control lever in slow posi-
tion, 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 (counterclock-
wise) 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 900to 1200 RPM. Re-
lease throttle lever.
ACCELERATION TEST -
• Move throttle control lever from slow to
fast position. If engine hesitates or dies,
tum idle mixture screw out (counter-
clockwise) 118tum. 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 govemor, which is factory set for
proper engine speed. Overspeeding the
engine above the factory high speed set-
ting can be dangerous. If you think the
engine-govemed high speed needs
adjusting, contact your nearest authorized
service center/department, which has
proper equipment and experience to make
any necessary adjustments.
ldleSpeed
Screw
e Mixture
few
ever
Idle Speed
Lever_
Idle Mixture
26