SERVICE A

ENGINE

TO ADJUST THROTTLE CONTROL CABLE

(See Fig. 29)

Loosen cable clamp screw to allow cable to move,

Move throttte control lever on upper handle to "FAST" position,

Pull throttle cable out until engine bellcrank is back as far as it will go,

°Hold cable in this position and tighten clamp screw securely.

CLAMP SCREW

THROTTLE

BELLCRANK

FIG. 29

TO ADJUST CARBURETOR (See Fig. 30)

The carburetor has a high speed jet and has been preset at the factory and adjustment should not be necessary. How- ever, minor adjustments 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 idle needle valve in (clockwise) decreases the supply of fuel to the engine giving a leaner fuel/air mixture. Turning the needle valve 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 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 idle needle valve in (clockwise) closing it finger tight and then turn valve out (counter- clockwise) 1-1/2 turns°

ADJUSTMENTS

FINAL SETTING

Start engine and allow to warm for five minute& Make final adjustments with engine running at idle and drive control bar in "DISENGAGED" position,,

With throttle control lever in "SLOW" position, turn idle needle valve in (clockwise) until engine begins to die then turn out (counterclockwise) until engine runs rough, Turn valve to a point midway between those two positions.

IDLE RPM ADJUSTMENT

To adjust idle RPM, rotate throttle linkage counter- clockwise and hold against stop while adjusting idle speed adjusting screw to obtain 1750 RPM. Release throttle linkage,

ACCELERATION TEST

Move throttle control lever from "SLOW" to "FAST" position° If engine hesitates or dies, turn needle valve

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 or damage may result.

IMPORTANT; NEVER TAMPER WITH THE ENGINE

GOVERNOR, WHICH IS FACTORY SET FOR PROPER

ENGINE SPEED. OVERSPEEDINGTHE ENGtNEABOVE

THE FACTORY HIGH SPEED SETTING CAN BE

DANGEROUS. IFYOUTHINKTHE ENGINE-GOVERNED

HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR NEAREST SEARS SERVICE CENTER, WHICH HAS

PROPER EQUIPMENT AND EXPERIENCE TO MAKE ANY NECESSARY ADJUSTMENTS.

THROTTLE LINKAGE

THROTTLE STOP

IDLE SPEED

IDLE NEEDLE VALVE

ADJUSTING SCREW

 

FIG. 30

19

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Craftsman 917.29555 manual Adjustments, To Adjust Throttle Control Cable, To Adjust Carburetor See Fig