Needle And Seat Leakage Test; Fuel Level Test - Polaris A12MH46AX Service Manual

CARBURATION AND FUEL SYSTEM
2. Illustration 2: With the carburetor still resting on the
level surface, use one hand to slightly tilt the
carburetor back. The float will then fall into the correct
position, with the float tongue resting lightly on the
inlet needle valve pin without compressing the spring.
The bottom of the float should be parallel with the float
bowl mating surface. Illustration 3: NOTE: If the float
is past parallel with the mating surface, the carburetor
has been tilted back too far and the float tongue is
likely compressing the needle valve pin.
3. Measure the height from the float bowl mating surface
to the top of step of the float as shown in Illustration
2. Both sides of float should be parallel to each other.
The measurement should be made at the mid–point
on top of the float using Float Adjustment Tool (PN
2872314) or a vernier caliper. When measuring the
height, be sure the inlet needle valve spring is not
compressed.
Float Bowl Height: 13-14 mm
4. If adjustment is necessary, bend the tongue slightly.
Be sure float measurement is even on left and right
side.
4.15
Float parallel with float
bowl mating surface
9923412 - 2012 Sportsman 400/500 and EFI Tractor Service Manual
© Copyright 2011 Polaris Sales Inc.

Needle and Seat Leakage Test

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.
Mity Vac

Fuel Level Test

A fuel level test can be performed on some models if the
drain hose fitting is accessible. Be sure to re–attach the
bowl drain hose after performing the test. A fuel level test
allows you to observe the height of the fuel in the float bowl
without removing the carburetor. The fuel level can be
observed with the engine either running or shut off,
however, engine must run briefly to allow fuel level to
stabilize.
1. Attach a clear line to drain fitting. Be sure line fits
tightly on fitting. Position hose along side of
carburetor as shown.
1.5 mm
.060 in.
2. Open bowl drain screw by turning counterclockwise
approximately two turns. Start and run engine for 3 to
5 seconds to allow fuel level to stabilize in the line. If
level is out of specification, remove carburetor and
inspect inlet needle and seat, float height, passages,
etc.
NOTE: If a line was removed to perform this procedure,
it must be replaced.
TM
(PN 2870975)
Bowl Mating
Surface