SERVICE AND ADJUSTMENTS
TO ADJUST CARBURETOR (See Fig. 32)
The carburetor has been preset at the factory and adjust-
ment should not be necessary. However, minor adjust-
ment 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) de-
creases the supply of fuel to the engine giving a leaner fuel/
air mixture. Turning the idle mixture valve out (counter-
clockwise) increases the supply of fuel to the engine giving
a richer fuel/air mixture.
IMPORTANT: DAMAGE TO THE NEEDLE VALVE AND
THE SEAT IN CARBURETOR MAY RESULT IF SCREW IS
TURNED IN TOO TIGHT.
PRELIMINARY SETTING -
•
Air cleaner assembly must be assembled to the carbu-
retor when making carburetor adjustments.
•
Be sure the throttle control cable is adjusted properly
(see above).
•
With engine off turn idle mixture valve in (clockwise)
closing it finger tight and then turn out (counterclock-
wise) 1 full turn.
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 (
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 in (clockwise) until en-
gine begins to die and then turn out (counterclockwise)
until engine runs rough. Turn valve to a point midway
between those two positions. Release throttle lever.
ACCELERATION TEST -
•
High speed stop is factory adjusted. Do not adjust -
damage may result.
IMPORTANT:
GOVERNOR, WHICH IS FACTORY SET FOR PROPER
ENGINE SPEED. OVERSPEEDING THE ENGINE ABOVE
T H E F A C T O R Y H I G H S P E E D S E T T I N G C A N B E
DANGEROUS. IF YOU THINK THE ENGINE-GOVERNED
HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR
N E A R E S T
DEPARTMENT, WHICH HAS PROPER EQUIPMENT AND
E X P E R I E N C E
ADJUSTMENTS.
) position. With
23
Move throttle control lever from slow (
position. If engine hesitates or dies, turn idle mixture
valve out (counterclockwise) 1/8 turn. Repeat test and
continue to adjust, if necessary, until engine acceler-
ates smoothly.
NEVER TAMPER WITH THE ENGINE
A U T H O R I Z E D
T O
M A K E
THROTTLE
LEVER
IDLE MIXTURE
VALVE
FIG. 32
) to fast (
)
S E R V I C E
C E N T E R /
A N Y
N E C E S S A R Y
IDLE SPEED
SCREW
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