Arctic Cat S2009BCDFCOSL, Operator'S Manual, Page: 52 / 88

48 MAINTENANCE
SELECTING
CARBURETOR MAIN
JETS
Altitude, temperature, and the use of
oxygenated gasoline affect the carbure-
tion needed for optimum engine perfor-
mance. The carburetor main jets must
be changed in conjunction with changes
in operating altitude, oxygenated gaso-
line usage, and temperature. As the
ambient temperature rises or as the
snowmobile is operated at a higher alti-
tude, the main jets must be replaced
with leaner main jets. The original
equipment (production) main jets may
need to be changed (depending on the
type of gasoline you are using, your
operating altitude, and temperature). A
Main Jet Chart decal is located beneath
the hood of the snowmobile. It should
be noted that when selecting the proper
main jets, it is better to be too rich rather
than too lean. To change carburetor
main jets, use the following procedure:

NOTE: Carburetor main jets may
be changed by the snowmobile
owner if qualified to do so. If the
owner does not feel qualified, take
the snowmobile to an authorized
Arctic Cat Snowmobile dealer for
this service. This service is at the
discretion and expense of the
snowmobile owner.
1. Loosen each carburetor flange
clamp and remove each carburetor
from the intake flange and boot.
2. Remove each drain plug and O-
ring from the carburetor float
chamber and drain the gas into a
small container or shop towels.
3. Using the main jet wrench (from
the tool kit), thread the main jet
out of each carburetor. Account for
the baffle ring/washer. Install the
new main jet and the existing baf-
fle ring/washer. Tighten the main
jet securely.
0728-054
4. Install each drain plug and O-ring;
then tighten securely.
5. Install and secure the carburetors.
SPARK PLUGS
(1100 cc Models)

NOTE: If spark plugs must be
replaced, take the snowmobile to
an authorized Arctic Cat Snowmo-
bile dealer for inspection and ser-
vice. This service is at the
discretion and expense of the
snowmobile owner.
! CAUTION
Use only GENUINE Mikuni brass
main jets. Also, if using an oxygen-
ated gasoline (up to 10% ethanol
or up to 15% MTBE), the carburetor
main jet must be one size larger
than the main jet required for regu-
lar unleaded gasoline.
! CAUTION
A main jet which is too small will
cause severe engine damage.
Engine damage caused by lean jet-
ting WILL NOT BE covered by Arc-
tic Cat warranty policy.
! WARNING
Whenever any maintenance is per-
formed on the fuel system, there
should be no welding, smoking,
open flames, etc., in the area.