To Adjust Carburetor; Acceleration Test - Craftsman 944.600191 Owner's Manual

SERVICE AND ADJUSTMENTS
CHOKE
CLAMP
SCREW
LEVER
FIG. 29
TO ADJUST CARBURETOR (See Figs. 30&
31)
The carburetor has been preset at the factory and adjust-
ment 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 ger)eral, tuming the mixture screw in (clockwise) de-
creases the supply of fuel tothe engine giving a leaner fuel/
air mixture. Turning the mixture screw out (counterclock-
wise) increasesthe supply offuel to the engine givinga richer
fuel/air mixture.
IMPORTANT: DAMAGE TO THE NEEDLES AND THE
SEATS IN CARBURETOR MAY RESULT IF SCREW IS
TURNED iN TOO TIGHT.
PRELIMINARY SETTING -
• Be sure you have a clean air filter, and the throttle control
cable and choke are adjusted properly (see above).
• With engine off turn idle mixture screw in (clockwise)
closing it finger tight and then turn out (counterclock-
wise) 1-1/4 to 1- 1/2 turns.
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.
• 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.
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.
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 -
• Move throttle control lever from slow to fast position. If
engine hesitates or dies, turn idle mixture screw out
(counterclockwise) 1/8turn. Repeat test and continue
to adjust, if necessary, until engine accele rates smoothly.
High speed stop is factory adjusted. Donot adjust-damage
may result.
IMPORTANT: NEVER TAMPER WITH THE ENGINE
GOVERNOR, WHICH IS FACTORY SET FOR PROPER
ENGINE SPEED. OVERSPEEDINGTHE ENGINE ABOVE
THE FACTORY HIGH SPEED SETTING CAN BE
DANGEROUS. IF YOU THINK THE ENGINE-GOVERNED
HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR
NEAREST AUTHORIZED SERVICE CENTER/
DEPARTMENT, WHICH HAS PROPER EQUIPMENT AND
EXPERIENCE TO MAKE ANY NECESSARY
ADJUSTMENTS.
IDLE SPEED
SCREW
IDLE MIXTURE
SCREW
LEVER
FIG. 30
LEVER
IDLE MIXTURE
SCREW
FIG. 31
23