Vent Systems (2 Cycle); Needle And Seat Leakage Test - 2 Cycle; Float Height Adjustment (2 Cycle); Assembly, Cv Carburetor - Polaris Trail Blazer Service Manual

FUEL SYSTEM/CARBURETION

Vent Systems (2 Cycle)

Vent Systems - 2 Cycle
The fuel tank and carburetor float bowl vent lines supply atmospheric pressure to the fuel in the tank and float
bowl. The lines must be free of kinks and restrictions to prevent lean mixture and possible engine damage. Vent
lines must be properly routed to prevent damage to the line and to prevent contaminants from entering the carbu-
retor or fuel tank.
A one-way check valve is in place on the bowl overflow hose, to allow overflow fuel out, and prevent water or other
contaminants from entering the bowl. (See photo below right).
To Frame
Check
Valve
Carburetor Venting (34MM)
Float Height - 2 Cycle
1. Invert the carburetor and remove float bowl.
2. Rest the float tongue lightly on the inlet needle valve
pin without compressing the spring.
3. Measure height from float bowl mating surface to float
arm as shown. Both sides of float arm must be parallel
to each other. Use float adjustment tool (PN 2872314)
or a vernier caliper. When measuring height, be sure
inlet needle valve spring is not compressed.
adjustment is necessary, bend the tongue slightly.
Float Height:
Parallel to Gasket Surface ±
VM 30
1mm
Parallel to Gasket Surface ±
VM 34
1mm

Needle and Seat Leakage Test - 2 Cycle

1. Install the float bowl. Invert the carburetor and install
a Mity-Vac™ (PN 2870975) to the fuel inlet fitting.
Apply 5 PSI pressure to inlet fitting. The needle and
seat should hold pressure indefinitely. If not, inspect
needle and seat and seat O-ring or gasket.
Polaris Sales Inc.
Carburetor Venting (30MM)
Float Arm
Gasket
Surface
If
4.16
To Frame
To "T"
Fitting
and
Check
Valve
Parallel
4/99