Craftsman 917.255520 - Manual (Page 24)

SERVICE AND ADJUSTMENTS
ENGINE
TO ADJUST THROTTLE CONTROL CABLE
(See Fig. 32)
The throttle control has been preset at the factory and ad­
justment 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 hoies "A" in governor control lever and hoie
in governor plate line-up. If holes "A" are not aligned,
loosen clamp screw and move throttle cable until holes
are aligned. Tighten damp screw securely.
FIG. 32
TO ADJUST CARBURETOR (See Fig. 33;
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, turnig idle mixture valve in (clockwise) de­
creases the supply of fuel to the engine giving a leanerfuel/
air mixture, Turning the idle mixture valve
out (counter­
clockwise) increases the supply of fuel to the engine givirig
a richer fuei/air mixture.
IMPORTANT: DÁMAGETOTHENEEDLEVALVE AND
THE SEAT IN CARBURETOR MAY RE­
SULT 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 (counterciock-
wise) 1 full turn.
FINAL SETTING -
• Start engine and allow to warm for five minutes. Make
final adjustments with engine running and shift/motlon
control lever in “NEUTRAL" position,
• Move throttie 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, Repeattestand
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 tS FACTORY SET
FOR PROPER ENGINE SPEED. OVER­
SPEEDING THE 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, WHICH HAS PROPER EQUIP­
MENT AND EXPERIENCETOMAKEANY
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