Craftsman 917.270732 owner manual To Adjust Carburetor

Models: 917.270732

1 60
Download 60 pages 23.15 Kb
Page 25
Image 25
TO ADJUST CARBURETOR

Check that holes "A" in governor control lever and hole in governor plate line-up. If holes "A" are not

aligned, loosen clamp screw and move throttle cable until holes are

aligned. Tighten clamp screw se- curely.

Governor

Control Lever Governor

Control Plate

\

\

 

 

Throttle

Holes "A"

Clamp Screw

Cable

 

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 limiter cap. The limiter cap cannot be removed without breaking the adjusting needle.

The carburetor has been preset at the factory and adjustment should not be necessary. 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 (counterclockwise) increases the supply of fuel to the engine giving a richer fueL/air mixture.

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

PRELIMINARY SETTING -

Air cleaner assembly must be as- sembled to the carburetor when

making carburetor adjustments.

Be sure the throttle control cable is adjusted propedy (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

position. 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, turn idle mixture valve full travel clockwise then

counterclockwise 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. If engine hesitates or dies, turn idle mixture valve out (counterclockwise) 1/8 turn. Repeat test and continue to adjust, if neces- sary, 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 setting can be dangerous. If you think the engine-govemed high speed needs adjusting, contact your nearest autho-

rized service center/department, which has proper equipment and experience to make any necessary adjustments.

Idle Speed

S

;Throttle

Idle Mixture valve__]

with Umiter

25

Page 25
Image 25
Craftsman 917.270732 owner manual To Adjust Carburetor