Polaris 400 H.O. Offroad Vehicle User Manual


 
104
MAINTENANCE
Carburetor
Your POLARIS ATV is calibrated at the factory for optimal perfor-
mance at altitudes ranging from zero to 6,000 feet (1800 m) and temper-
atures of +40 degrees F. (4 degrees C.) or higher. Above 6000 feet (1800
m) the engine air/fuel mixture becomes overly rich and the engine loses
approximately 3% of its power for each 1000-foot (304.8 m) increase in
elevation. Although this power cannot be regained, adjustments to the
carburetor and drive system can be made to allow more efficient opera-
tion. Optional jets, available from your POLARIS dealer, are required
for operation above 6,000 feet and temperatures below +40 degrees F. (4
degrees C.)
Continuous operation of the engine without proper jetting when
required can cause poor performance, overheating or PVT or engine
damage. See your POLARIS dealer for more information about jetting
the ATV for conditions in your area.
Pilot screws are sealed with metal plugs and are serviceable only by
POLARIS dealers.
Carburetor/Engine Idle RPM Adjustment
Recommended engine idle RPM is 1200 +/- 200. If the engine idle
speed is unsatisfactory and all other conditions are favorable, the carbu-
retor can be adjusted.
1. Start the engine and allow it to
warm up for approximately five
minutes.
2. Place the transmission in gear.
3. Lock the parking brake.
4. Turn the screw in (clockwise) to
raise RPM. Turn the screw out
(counter-clockwise) to lower
RPM.
Idle Screw