SIERV OE AND ADJUSTMENTS

ENGINE

ACCELERATION TEST -

o Move throttle control lever from slow (,_m.) to fast (,@)

TO ADJUST THROTTLE CONTROL CABLE

(See Fig. 35 and 36)

The throttle control has been preset at the factory and adjustment should not be necessary Check adjustment as described below before loosening cable. If adjustment is necessary, proceed as follows:

oWith engine not running, move throttle control lever to fast (,f_) position.

Checkthat speed control lever is against step screw. If it is not loosen casing clamp screw and pull throttle cable until lever is against screw. T ghten c amp screw securely.

TO ADJUST CARBURETOR (See Fig. 37)

The carburetor has been preset at the factory and adjust- ment should not be necessary However, minoradjustment

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 fuel/air mixture. Turning the adjusting needles out (coun- terclockwise) 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 tS

TURNED IN TOO TIGHT

PRELIMINARY SETTING -

oBe sure you have a clean air fiiter, and the throttle control cable is adjusted properly (see above),

,,With engine off turn idle fuel adjusting needle in (clock- wise) dosing it finger tight and then turn out (counter- clockwise) 1-II4 turns.

oTurn main fuel adjusting needle in (clockwise) closing finger tight and then turn out (countercfockwise) l turn.

FINAL SETTING -

oStart engine and alfow to warm for five minutes.. Make final adjustments with engine running and shift/motion control lever in neutral (N) position.

oWith throttle control lever in fast ( '_ ) position, turn main fuel adjusting needle in (clockwise) until engine

beg!ns to die then turn out (counterclockwise) until engine runs rough Turn needle to a point midway between those two positions.

oIdle speed setting - 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) until engine runs rough.. Turn needle to a point midway between those two positions

Recheck idle speed. Readjust if necessary.

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 acceler-

ates smoothly.

High speed stop is factory adjusted. Do not adjust-damage may resulL

IMPORTANT: NEVER TAMPER WITH THE ENGINE GOVERNOR, WHICH IS FACTORY SET FOR PROPER

ENGtNESPEED OVERSPEEDINGTHEENGINEABOVE

THE FACTORY HIGH SPEED SETTING CAN BE

DANGEROUS, IF YOU THINKTHE ENGINE-GOVERNED

HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR

NEAREST AUTHORIZED SERVICE CENTER/ DEPARTMENT, WHICH HAS PROPER EQUIPMENT AND

EXPERIENCE TO MAKE ANY NECESSARY ADJUSTMENTS

CASING

STOPSCREW

SPEED CONTROL

CLAMP

 

LEVER

THROTTLE

CONTROL

CABLE

FIG, 35

STOP

SCREW

SPEED

CONTROL

LEVER

FIG, 36

_x_

/IDLEFUEL

IDLE SPEED

ADJUSTING

ADJUSTING

 

SCREW ,--,..,,.---"

 

FIG,. 37

26

Page 26
Image 26
Sears 917.25148 manual To Adjust Throttle Control Cable, To Adjust Carburetor See Fig