Sears 917.25049 Lawn Mower User Manual


 
SERVmCE AN ADJUSTMENTS
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ENGINE ACCELERATIONTEST-
TO ADJUST THROTTLE CONTROL CABLE
(See Figs, 34 & 35)
The throttle control has been preset at the factory and
adjustment should notbe necessary.. Checkadjustment as
described below before loosening cable. If adjustment is
necessary, proceed as follows:
o With engine not running, move throttle control lever to
fast (,_) position°
, Checkthat speed control lever isagainst stop screw, if
it is not, loosen casing clamp screw and put! throttle
cable until lever isagainst screw. Tighten clamp screw
securely.
o 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
cont{nue to adjust, if necessary, until engine acceler-
ates smoothtyo
High speed stop isfactory adjusted_ Do not adjust-damage
may result,
IMPORTANT: NEVER TAMPER WITH THE ENGINE
GOVERNOR, WHICH IS FACTORY SET FOR PROPER
ENGINE SPEED. OVERSPEEDLNG THE ENGINE ABOVE
THE FACTORY HIGH SPEED SETTING CAN BE
DANGEROUS. IF YOU THINK THE ENGINE-GOVERNED
HLGH SPEED NEEDS ADJUSTING, CONTACT YOUR
NEAREST AUTHORIZED SERVICE CENTER/
DEPARTMENT, WHICH HAS PROPER EQUIPMENT AND
EXPERIENCE TO MAKE ANY NECESSARY
ADJUSTMENTS..TO ADJUST CARBURETOR (See Fig. 36)
The carburetor has been preset at the factory and adjust_
merit should notbe 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 adjusting needles in (clockwise)
decreases the supply of fuel to the engine giving a leaner
fueVair mixture. Turning the adjusting needles out (coun-
tercleckwise) increases the supply of fuel to the engine
giving a richerfuel/air mixture.
IMPORTANT: DAMAGE TO THE NEEDLES AND THE
SEATS IN CARBURETOR MAY RESULT IF SCREW {S
TURNED IN TOO TIGHT.
PRELIMINARY SETTING -
= Be sure you have a clean air filter, and the throttle
control cable is adjusted properly (see above)°
° With engine off turn idle fuel adjusting needle in (clock-
wise) closing it finger tightand then turn out (counter-
clockwise) 1o114turns.
° Turn main fuel adjusting needle in (clockwise) closing
fingertight and then turn out (counterclockwise) 1turn
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 infast (,t_) position, turn main
fuel adjusting needle in (clockwise) untilengine begins
to die then turn out (counterclockwise) until engine
runs rough° Turn needle to a point midway between
those two positions.
° Idle sDee.dsetting - With throttle control lever in slow
(,,_) position, engine should idle at 1400 RPM If
engine idles too slow or fast, turn idle speed adjusting
screw in or out until correct idle is attained..
. Idle fuel needle setting - With throttle control lever in
slow (,,€_) position,turn idle fuel adjusting needle in
(clockwise) until engine begins to die and then turn out
(counterclockwise) untilengine runs rough. Turn needle
to a point midway between those two positions.
o Recheck idle speed. Readjust if necessary.
CASING STOP SCREW SPEED CONTROL
LEVER
THROTTLE
CONTROL
CABLE
FIG. 34
STOP
SCREW
SPEED
CONTROL
LEVER
FIG. 35
IDLE SPEED o_ _ IDLEFUEL
27 FIG. 36