Sears 917.25559 - Manual (Page 24)

SERVICE AND ADJUSTMENTS
ENGINE
TO ADJUST THROTTLE COMTROL CABLE
(See Fig. 33)
The throttle control has been preset at the factory and
adjustment should not be necessary. Check adjustment as
described below before loosening cable. If adjustment is
necessary, proceed as follows:
» With engine not running, move throttle control lever
from "SLOW" to "CHOKE" position. Slowly move lever
from "CHOKE" to "FAST" position.
' 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 securely,
GOVERNOR
CONTROL LEVER
GOVERNOR
CONTROL PLATE
HOLES "A CLAMP
SCREW
THROTTLE
CABLE
FIG. 33
TO ADJUST CARBURETOR (See Fig. 34j
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 ieanerfuel/
air mixture. Turning the idle mixture valve out (counter­
clockwise) increases the supply of fuel to the engine giving
a richer fuei/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 assem bled 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" 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 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 -
• 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 necessary, until engine acceler­
ates 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 THINKTHE ENGINE-GOVERNED
HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR
NEAREST AUTHORIZED
SERVICE
CENTER, WHICH HAS
PROPER EQUIPMENT AND EXPERIENCE TO MAKE ANY
NECESSARY ADJUSTMENTS.
FIG. 34
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