Arctic Cat Cougar Service Manual page 137

ADJUSTMENTS FOR SPECIAL USE
In addition, the pilot air screw controls mixture
adjustment when the throttle is opened from idle
to the full open position quickly and when the
engine is run at half-throttle. Note the following
when adjusting the pilot air screw:
a. Turning the pilot air screw clockwise closes
the pilot air and richens the fuel mixture at
idle.
b. Turning the pilot air screw counterclock-
wise leans the fuel mixture.
0
Throttle
valve
127
c. Pilot jets are identified by number. Pilot jets
with larger numbers will flow more fuel
than jets with smaller numbers. Installing
jets with larger numbers will richen the fuel
mixture.
d. When operating the snowmobile in rela-
tively warm weather or at a higher altitude,
tum the pilot air screw counterclockwise.
When operating the snowmobile in exces-
sively cold weather conditions, tum the pi-
lot air screw clockwise to richen the
mixture.
1. Open the hood.
NOTE
Figure 2 shows the carburetor removed
for clarity.
2. Locate the pilot air screw (A, Figure 2) on the
side of each carburetor.
3. Tum the pilot air screws in until they seat very
lightly.
4. Back the screws out the number of turns
specified for your model in Table 2.
5. Start the engine and allow it to warm to
normal operating temperature.
6. Adjust the throttle stop screw (B, Figure 2)
until the engine is idling as near as possible to
the correct idle speed listed in Table 1.
NOTE
While adjusting the pilot air screws in
Step 7, it will occasionally be necessary
to tum the idle speed stop screws (B,
Figure 2) counterclockwise to keep the
idle speed at 1,500-2,000 rpm. Maintain
the speed as close to the idle speed listed
in Table 2 as possible.
7. Begin turning the pilot air screws (A, Figure
2) slowly counterclockwise until the engine is
idling smoothly at the highest engine speed.
Turning the pilot air screws counterclockwise
will richen the fuel mixture.
8. To check the pilot air screw setting, proceed
as follows: