Craftsman 917.270512 owner manual Toadjust Carburetor

Models: 917.270512

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TOADJUST CARBURETOR

TOADJUST CARBURETOR

NOTE:The carburetoron this engine is low emission. It is equipped with an idle

fuel adjustingneedlewith a limiter cap, which allows some adjustmentwithin the

limits allowed by the cap. Do not attempt to remove the limiter cap. The limiter cap cannot he 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:

In 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 (countemlockwise) increases the supply of

fuel to the engine giving a richer fuel/air mixture.

IMPORTANT: Damage to the needle valve and the seat incarburetor may result if screw is tumed in too tight.

PRELIMINARY SETTING -

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 -

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

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.

While still holding throttle lever against idle speed screw, tum idle mixture valve

full travel clockwise then countemlock- wise until engine runs roO_il: T_aive

to a point midway between those two

positions. Release throttle lever.

ACCELERATION TEST -

Move throttle control lever from slow to fast position. If engine hesitates or dies, turn idle mixture valve out (counter- clockwise) 1/8 tum. 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 govemor, 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

Idle Mixture

Valve With

Limiter

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Craftsman 917.270512 owner manual Toadjust Carburetor