2009 Polaris Scrambler 500 4x4 2x4 factory service manual, Page 111Get this manual

2009 Polaris Scrambler 500 4x4 2x4 factory service manual, Page 111

FUEL SYSTEMCARBURETION CARBURETOR OPERATION CONT'D When the throttle plate is opened and engine speed begins to increase,
only, and are not true representations of Mikuni BST carburetor PILOT (IDLE AND SLOW) SYSTEM This system supplies fuel during
engine operation with throttle valve closed (1) or slightly openedThe fuel from float chamber (2) is metered by pilot jet
(3) where it mixes with air coming in through pilot air jet (4)The mixture then goes up through pilot passage to pilot screw
(5)A part of the mixture is discharged into the main bore out of bypass ports (6)The remainder is then metered by pilot screw
and discharged into the main bore through pilot outlet (7) Fuel is drawn into the starter circuit from the float chamber
(2) through the starter jet (3)Starter jet meters this fuel, which then flows into starter pipe (4) and mixes with the air
(7) coming from the float chamberThe mixture, rich in fuel content, reaches starter plunger and mixes again with the air
coming through passage (8) extending from underneath the diaphragmThe rich fuelair mixture for starting is discharged through