Craftsman 917.270631 To Adjust Carburetor, Preliminary Setting, Final Setting, Acceleration Test

TO ADJUST CARBURETOR

NOTE: The carburetor on this engine is low emission° it is equipped with an idle fuel adjusting needle with a limiter cap, which allows some adjustment within the limits allowed by the cap. Do not attempt to remove the lirniter cap. The limiter cap cannot be removed without breaking the adjusting needle_

The carburetor has been preset at the fac- tory and adjustment should not be neces- sary. 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:

tn general, turning idle mixture valve in (clockwise) decreases the supply of fuel to the engine giving a leaner fuel/air mixture. Turning the idle mixture valve out (counterclockwise) increases the supply of fuel to the engine giving a richer fuel/air mixture.

BtVJPORTANT: Damage to the needle valve and the seat in carburetor may result if screw is turned in too tight.

PRELIMINARY SETTING

o Air cleaner assembly must be assem- bled to the carburetor when making car- buretor adjustments.

,,Be sure the throttle control cable is adjusted properly (see above).

FINAL SETTING

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

o Move throttle control lever to slow posi- tion. With finger, rotate and hold throttle lever against idle speed screw. Turn idle speed screw to attain 1750 RPM.

o While still holding throttle lever against

idle speed screw, turn idle mixture valve full travel clockwise then counterclock-

wise until engine runs rough. Turn valve to a point midway between those two

positions. Release throttle lever_

ACCELERATION TEST

,,Move throttle control lever from slow to fast position, tf engine hesitates or dies, turn idle mixture valve out (counter- clockwise) 1/8 turn. Repeat test and continue to adjust, if necessary, until

engine accelerates smoothly.

High 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, overspeeding the engine above the factory high speed set- ting can be dangerous, if you think the engine-governed high speed needs adjusting, contact your nearest authorized service center, which has proper equip- ment to make any necessary adjustments.

Idle Speed	Throttle
Screw	Lever

idtJMixture_

Valve With f-

Limiter

26