Craftsman 917.257360 - Manual (Page 25)

SERVICE AND ADJUSTMENTS
ENGINE
TO ADJUST THROTTLE CONTROL CABLE
(See Fig. 36)
The throttle control has been preset at the factory and ad­
justment should not be necessary Check adjustment as
described below before loosening cable if adjustment is
necessary, proceed as follows;
■ With engine not running, move throttle control lever
from "SLOW" to "CHOKE" position. Slowly move lever
from "CHOKE" to "FAST" position.
• Check that hole in governor control lever and hole in
governor plate line-up. If holes "A" are not aligned,
loosen clamp screw and move throttle cable until holes
are aligned. Tighten clamp screw securely.
TO ADJUST CARBURETOR (See Fig. 36)
The carburetor has been preset at the factory and adjust­
ment should not be necessary. However, minor adjust­
ment may be required to com pensate for differences in fuel,
temperature, altitude or load If the carburetor does need
adjustment, proceed as follows:
In general, turning the mixture screws in (clockwise) de­
creases the supply of fuel to the engine giving a leaner fuel/
air mixture Turning the mixture screws out (counterclock­
wise) 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 SCREWS ARE TURNED IN TOO
TIGHT.
PRELIMINARY SETTING -
• Air cleaner assembly must be assembled to the carbu­
retor when making carburetor adjustments
• Be sure the throttle control cable is adjusted properly
(see above)
• With engine off turn high speed mixture screw in
(clockwise) closing it finger tight and then turn out
(counterclockwise) 1-1/4 to 1-1/2 turns
• Turn idle mixture screw in (clockwise) closing finger
tight and then turn out (counterclockwise) 1 turn
FINAL SETTING -
•
Start engine and allow to warm for five minutes, Make
final adjustments with engine running and shift/motion
control lever in “NEUTRAL" position
• With throttle control lever in "FAST" position, turn high
speed mixture screw in (clockwise) until engine begins
to die then turn out (counterclockwise) until engine
runs rough Turn screw to a point midway between
those two positions
• With throttle control lever in "SLOW" posit!on,_turn idje
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
GOVERNED IDLE-
•
Move throttle control lever to "SLOW" position. With
finger, hold throttle shaft in closed position against
throttle stop (counterclockwise). Turn idle speed screw
to attain 1550 RPM. Release throttle shaft Move
throttle control lever to attain 1750 RPM. Turn governor
idle screw until it contacts governor control lever.
ACCELERATIONTEST-
• 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 necessary, until engine accel­
erates smoothly.
High speed stop is factory adjusted,
damage may result.
Do not adjust
IMPORTANT: NEVER TAMPER WITH THE ENGINE
GOVERNOR, WHICH IS FACTORY SET
FOR PROPER ENGINE SPEED. OVER­
SPEEDING THE ENGINE ABOVE THE
FACTORY HIGH SPEED SETTING CAN
BE DANGEROUS IF YOU THINK THE
ENGINE-GOVERNED HIGH SPEED
NEEDS ADJUSTING, CONTACT YOUR
NEAREST AUTHORIZED SERVICE
CENTER, WHICH HAS PROPER EQUIP­
MENT AND EXPERIENCETO MAKE ANY
NECESSARY ADJUSTMENTS
FIG. 36
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