Sears 917.25147 Lawn Mower User Manual


 
SERVICE ADJUSTMENTS
With engine not running, move choke control (located
on dash panel) to full choke (Ikl) position.
Remove air cleaner cover, filter and cartridge plate to
expose carburetor choke (see "AIR FILTER" in the
Customer Responsibilities section of this manua0.
Choke shouldbeclosed, lfit isnot, oosencasingclamp
screw and move choke cable until choke is completely
closed. Tighten casing c_amp screw securely.
Reassemble a_rcleaner.
CHOKE CLOSED _,
_CHOKE
LEVER
While still holding throttle lever against idle speed
screw, turn idle mixture screw in (clockwise) unti
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 speea screw
and adjust _o_eseeed screw to obtain 900 to 1200
RPM. Release throttle lever.
ACCELERATION TEST -
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 adjusL if necessary, until engine accel-
erates smooth y.
.High speed S,OD iS factory adjusted Do not aajusz -
aamage may result.
IMPORTANT: NEVER TAMPER WITH THE ENB NE
GOVERNOR WHICH q FACTORY SET FOR PROPER
ENGINE SPEED OVERSPEEDINGTHEENGINEABOVE
THE FACTORY HIGH SPEED SETTING CAN BE
DANGEROUS IF YOU THINK THE ENGINE-GOVERNED
HIGH SPEED NEEDS ADJUSTING. CONTACT YOUR
NEAREST AUTHORIZED SERVICE CENTER/
DEPARTMENT WHICH HAS PROPER EQUIPMENT AND
EXPERIENCE TO MAKE ANY NECESSARY
ADJUSTMENTS
FiG. 29
TO ADJUST CARBURETOR (See Figs. 30 &
31)
The carburetor nas been oreset at me factory and adjust-
ment should not De necessary, However. minor adjust-
ment may Derequired to co mpensate for differences infuel.
temperature, altitude or load. If the carburetor does need
adjustment, proceed as follows:
Ir =c,,eral. turning [he _,,,..... screw in {clockwise de-
creases the supply of fuel to the engine gwing a leaner fuel/
air mixture. Turning the mixture screw 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 '4 CARBURETOR MAY RESULT _= SCREW S
TURNED tN TOOTIGHT.
PRELIMINARY SETTING
Be sure you nave a clear air filter ana me mrottle
control cable ana cnoKe are aajustea properly ,see
aoove,.
With engine off turn idle mixture screw in (clockwise)
closing it finger tight and then turn out (counterclock-
wise) 1-1/4 to 1-!/2 t!!ms.
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 (,_!) position, hold
throttle lever against idle speed screw and adjust idle
speed screw to obtain 1200 to 1400 RPM.
DLE SPEED
SCREW
SCREW
FIG. 30
IDLE SPEED _--' - ./----(_-_
SCREW
THROTTLE / IDLE MIXTURE
LEVER SCREW
FIG. 31
25