Husqvarna 917.289541 - Manual (Page 24)

24
IDLE FUEL
ADJUSTING
NEEDLE
02726
IDLE SPEED
ADJUSTING
SCREW
02725
CABLE
CLAMP
SCREW
SPEED CONTROL
BRACKET
THROTTLE
LEVER
ENGINE
Maintenance, repair, or replacement of the emission con trol
devices and systems, which are being done at the cus tom-
ers expense, may be performed by any non-road engine
repair establishment or individual. Warranty repairs must
be performed by an authorized engine man u fac tur er's
service outlet.
TO AD JUST THROTTLE CON TROL CABLE
(See Fig. 36)
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 to see if hole in throttle lever and hole in speed
control bracket are aligned.
• If holes are not aligned, loosen cable clamp screw and
align the holes by inserting a pencil or a 1/4" drill bit
through both holes.
• Pull throttle cable up to remove slack and tighten cable
clamp screw. Remove alignment pencil or drill bit.
TO ADJUST CARBURETOR (See Fig. 37)
The carburetor has been preset at the factory and ad just-
ment should not be necessary. However, minor ad just 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 the adjusting needles in (clock wise)
de creases the supply of fuel to the engine giving a leaner
fuel/air mixture. Turning the adjusting needles out (coun-
ter clock wise) increases the supply of fuel to the engine
giving a richer fuel/air mixture.
IMPORTANT: DAMAGE TO THE NEEDLES AND THE SEATS
IN CAR BU RE TOR MAY RESULT IF NEEDLE IS TURNED IN
TOO TIGHT.
NOTE: The carburetor on this engine is low emission.
It is equipped with an idle fuel adjusting needle with a
limiter cap, which allows some adjustment within the limits
al lowed by the cap. Do not attempt to remove the limiter
cap. The limiter cap cannot be removed without breaking
the adjusting needle.
• Be sure you have a clean air filter and the throttle
control cable is adjusted properly (see above).
• Start engine and allow to warm for five minutes. Make
adjustments with engine running and shift/motion con trol
lever in neutral (N) position.
• Idle speed setting - With throttle control lever in slow
position, en gine should idle at 1750 RPM. If engine
idles too slow or fast, turn idle speed adjusting screw
in or out until correct idle is at tained.
• Idle fuel needle setting - With throttle control lever
in slow po si tion, turn idle fuel adjustment needle in
(clock wise) until engine begins to die and then turn out
(coun ter clock wise) until engine runs rough. Turn nee dle
to a point midway be tween those two positions.
• Recheck idle speed. Readjust if necessary.
ACCELERATION TEST -
• Move throttle control lever from slow to fast position. If
engine hesitates or dies, turn idle fuel adjusting needle
out (counterclockwise) 1/8 turn. Re peat test and con-
tin ue to adjust, if necessary, until engine ac cel er ates
smoothly.
High speed stop is factory adjusted. Do not adjust - dam-
age may result.
IMPORTANT: NEVER TAMPER WITH THE ENGINE
GOVERNOR, WHICH IS FACTORY SET FOR PROPER ENGINE
SPEED. OVER SPEED ING 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/
DEPARTMENT, WHICH HAS PROPER EQUIP MENT AND
EXPERIENCE TO MAKE ANY NEC ES SARY ADJUSTMENTS.
SERVICE AND ADJUSTMENTS
Fig. 36
Fig. 37