Arctic Cat Z Series 2006, Operator'S Manual

Page: 50 / 88

MAINTENANCE 49
Fine-Tuning Fuel Mixture
Screws, Air Screws, and Idle
Speed Screw
1. While counting the rotations,
carefully rotate the fuel mixture
screws clockwise until lightly
seated.
0735-774
2. Rotate the fuel mixture screws
counterclockwise the exact
number of rotations ± 1/4 turn
from the seated position as an
initial setting.
3. While counting the rotations,
carefully rotate the air screws
clockwise until lightly seated.
4. Rotate the air screws counter-
clockwise the exact number of
rotations ± 1/4 turn from the
seated position as an initial set-
ting.
5. With the snowmobile on a
shielded safety stand, start the
engine, release the brake lever
lock, and thoroughly warm up.

NOTE: Make engine idle adjust-
ment only after the engine has
reached running temperature.
Allow engine to warm up for 2-3
minutes.
6. After the engine has been thor-
oughly warmed up, fine-tune
the idle speed screw until the
engine idles smoothly.

NOTE: If a tachometer is being
used, engine idle speed should
be approximately 1500 RPM.
! CAUTION
D o n o t fo rc e a f u e l m i x t u r e
screw when rotating it clock-
wise; damage to the fuel mix-
ture screw taper will result.
! CAUTION
The fuel mixture screw setting is
very critical to engine perfor-
mance; therefore, do not rotate
the fuel mixture screws less
than the recommended number
of turns counterclockwise or
engine damage will occur.
! CAUTION
Do not force an air screw when
rotating it clockwise; damage to
the air screw will result.
! WARNING
It is important that the rear of
the snowmobile is on a shielded
safety stand. If not, personal
injury could result.
! WARNING
DO NOT stand behind the snow-
m o b i l e o r n e a r t h e ro t a t i n g
track. NEVER run the track at
high speed when the track is
suspended.
! WARNING
If a tachometer is not available,
care must be taken not to adjust
engine idle speed too high.