Sears 917.256543 manual To Adjust Throttle Control Cable, To Adjust Carburetor See Fig

Models: 917.256543

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SERVnCE AN ADJUSTMENTS

ENGINE

TO ADJUST THROTTLE CONTROL CABLE

(See Fig. 32)

The throttle control has been preset at the factory and

adjustment should not be necessary° Check adjustmentas described below before loosening cable_ If adjustment is

necessary, proceed as follows:

,,With engine not running, move throttle control lever from slow [_) to choke (t'-.!)position. Slowly move lever from choke (N) to fast (,_,) position.

-Check to see if hole in throttle lever and hole in speed control bracket are aligned.

oIf holes are not aligned, loosen cable clamp screw and align the holes by inserting a pencil or a 1/4" drill bit through both holes.,

Pull throttle cable up to remove slack and tighten cable clamp screw. Remove alignment pencil or drilt bit..

TO ADJUST CARBURETOR (See Fig, 33)

The carburetor has been preset at the factory and adjust- ment should not be necessary. However, minor adjust- merit may be required to compensate for differences in fuel, temperature, altitude or toad. 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 (counter- clockwise) increases the supply of fuel to the engine giving a richer fuel/air mixture..

IMPORTANT: DAMAGE TO THE NEEDLES AND THE SEATS tN CARBURETOR MAY RESULT IF NEEDLE iS

TURNED IN TOO TIGHT..

NOTE: The carburetor on this engine is low emission_ it is equipped with an idle fuel adjusting needle with a ]imiter cap, which allows some adjustment within the Iimits allowed by the cap. Do not attempt to remove the timiter cap. The timitercap cannot be removed without breaking the adjusting needle.

-Be sure you have a clean air filter and the throttle control cable is adjusted properly (see above).

-Start engine and allowto warm for five minutes. Make adjustments with engine running and shift!motion control lever in neutral (N) position.

°idle speed setting - With throttle control lever in slow (,_) position, engine should idle at 1750 RPM. If engine idles too slow or fast, turr_ idle speed adjusting screw in or out until correct idle is attained_

oIdle fuei needle settincl - With throttle control lever in slow (,_) position, turn idle fuel adjustment needle in (clockwise) untif engine begins to die and then turn out (counterclocI_vise) until engine runs rough. Turn needle to a point midway between those two positions.

=Recheck idle speed. Readjust if necessary.

ACCELERATION TEST -

-Move throttle control lever from slow (-_) to fast (,_)

position, If engine hesitates or dies, turn idle fuel

adjusting needle out (counterclockwise) 1/8 turn. Re-

peat test and continue to adjust, if necessary, until engine accelerates smoothly..

Nigh speed stop is factory adjusted° Do not adjust - damage may result.

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

THE FACTORY HIGH SPEED SETTING CAN BE DANGEROUS.. IF YOU THINK THE ENGINE-GOVERNED

HtGH SPEED NEEDS ADJUSTING, CONTACT YOUR

NEAREST AUTHORIZED SERVICE CENTER/

DEPARTMENT, WHICH HAS PROPER EQUIPMENT AND

EXPERIENCE TO MAKE ANY NECESSARY ADJUSTMENTS.

CABLE

CLAMP

SCREW,

SPEED

BRACKET

THROTTLE

LEVER

FIG, 32

IDLE SPEED

ADJUSTING

IDLE FUEL /

iADJUSTING

!NEEDLE

FIG. 33

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Sears 917.256543 manual To Adjust Throttle Control Cable, To Adjust Carburetor See Fig, Turned in TOO Tight