Carburetor Specifications; Optional Main Jets; Carburetor Operation; Sportsman - Polaris SCRAMBLER 50 Service Manual

CARBURETOR
SPECIFICATIONS
The carburetor has been updated to accommodate
the choke system. The oil check valve has a higher
resistance spec to eliminate leaking oil into the carb.
Scrambler 50
Cutaway
Air Screw 1/2 turn out from lightly seated
Needle & Seat
Pilot Jet
Main Jet
E--Clip
Scrambler 90 - - Sportsman 90 - - Predator 90
Cutaway
Air Screw 1 turn out from lightly seated
Needle & Seat
Pilot Jet
Main Jet
E--Clip

OPTIONAL MAIN JETS

Part Number Size
3131337 65
3131338 67.5
3131339 70
3131340 72.5
3131341 75
3131342 77.5
3.4
3.0
1.2
25
75
#3 from top
3.0
1.5
25
82.5
#4 from top
Part Number Size
3131343 80
3131344 82.5
3131345 85
3131346 87.5
3131347 90
FUEL SYSTEM/CARBURETION
CAUTION:
A main jet that is too small will cause a lean
operating condition resulting in serious engine
damage.
HIGH ALTITUDE OPERATION
2003 Youth ATVs have been tested to 12,000 ft above
sea level to assure satisfactory performance. No
jetting or clutching changes are required for high
altitude operation.
CARBURETOR JETTING
IMPORTANT: The following guidelines must be
followed when establishing a main jet setting:
1. Select the lowest anticipated temperature at
which the machine will be operated.
2. Determine the lowest approximate altitude at
which the machine will be operated.
3. Select the correct main jet from the chart in the
specifications section.
CAUTION:
A main jet that is too small will cause a lean
operating condition resulting in serious engine
damage. Select the correct main jet carefully for
elevation and temperature according to the
charts in the Specifications section or in the
Owner's Safety and Maintenance Manual for each
particular model.

CARBURETOR OPERATION

The function of a carburetor is to produce a
combustible air/fuel mixture by breaking fuel into tiny
particles in the form of vapor, to mix the fuel with air
in a proper ratio, and to deliver the mixture to the
engine. A proper ratio means an ideal air/fuel mixture
which can burn without leaving an excess of fuel or air.
Whether the proper mixture ratio is maintained or not
is the key to efficient engine operation.