2.Remove air cleaner cover, filter and cartridge plate to expose carburetor choke (see =AIR FILTER" in the

Maintenance section of this manual).

3.Choke should be closed. If it is not,

loosen casing clamp screw and move choke cable until choke is completely

closed. Tighten casing clamp screw securely.

4 Reassemble air cleaner.

Chok

Choke

CasingLever Clamp

Screw

TO ADJUST CARBURETOR

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 the mixture screw in (clockwise) decreases the supply of fuel to the engine giving a leaner fueVair mixture. Turning the mixture screw out (counterclockwise) increases the supply of fuel to the engine giving a richer fueV air mixture.

IMPORTANT: Damage to the needles and the seats in carburetor may result if screw is turned in too tight.

PRELIMINARY SETTING -

1.Be sure you have a clean air filter, and the throttle control cable and choke are adjusted propedy (see above).

2.With engine off turn idle mixture screw in (clockwise) closing it finger tight

and then turn out (counterclockwise) 1-1/4to 1-1/2 turns.

FINAL SETTING -

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

2.With throttle control lever in slow

position, hold throttle lever against idle speed screw and adjust idle speed screw to obtain 1200 to 1400 RPM.

3.While still holding throttle lever against idle speed screw, turn idle mixture screw In (clockwise) until engine begins to die and then turn out (counterclockwise) until engine runs rough. Turn screw to a point midway between those two positions.

4.Continue to hold throttle lever against idle speed screw and adjust idle speed screw to obtain 900 to 1200 RPM. Release throttle lever.

ACCELERATION TEST -

5.Move throttle control lever from slow to fast position. If engine hesitates or dies, tum idle mixture screw out (countemlockwise) 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-governed high speed needs

adjusting, contact your nearest Sears or other qualified service center, which has proper equipment and experience to make any necessary adjustments.

e Mixture

rew

6

Lever

Idle Speed

Lever _

Idle Mixture Screw

28

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Image 28
Craftsman 917.27184 owner manual To Adjust Carburetor, Preliminary Setting, Final Setting, Acceleration Test