Polaris 2012 Sportsman Forest 500 International, Service Manual

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4.12
CARBURATION AND FUEL SYSTEM
© Copyright 2011 Polaris Sales Inc.
9923412 - 2012 Sportsman 400/500 and EFI Tractor Service Manual
Throttle Opening vs. Fuel Flow
In a full throttle condition the cross sectioned area
between the jet needle and the needle jet is larger than the
cross sectioned area of the main jet. The main jet therefore
has greater control over fuel flow.
Carburetor Disassembly – Mikuni CV
Use the following disassembly, assembly, and inspection
techniques to service a CV carburetor.
1. Remove carburetor diaphragm chamber cover with a
ratchet style screwdriver. DO NOT use an impact
driver to remove the screws or carburetor may be
permanently damaged.
2. Remove float bowl. Remove the float pin screw. The
float and float pin can be removed.
3. Remove inlet needle seat retaining screw along with
plate, and carefully remove needle seat.
NOTE: Do
not use a pliers to remove the seat or permanent
damage may occur.
4. Remove the pilot mixture screw, spring, flat washer,
and O–Ring. If an anti–tamper plug is installed over
the pilot screw cavity, it must be removed for access.
Closed
Throttle One-half
Throttle
Full
Throttle
Small
Clearance
Medium
Clearance Large
Clearance
Remove Screw
O-Ring
Washer
Spring
Pilot Screw