Fuel System; Fuel Pump Construction - KYMCO XCITING 500 Service Manual

5
. FUEL SYSTEM/FUEL PUMP
/FUEL TANK/CARBURETOR
XCITING 500

FUEL SYSTEM

The fuel pump is operated by an electromagnetic force and its electrical energy is supplied from the
battery. The fuel sent under pressure by the fuel pump flows into the float chamber when the float of
the carburetor has dropped and the needle valve is open. When the needle valve closes, the pressure of
the fuel in the hose connecting the carburetor and the fuel pump increases, and when the set pressure
is reached, the operation of the fuel pump is stopped by the fuel pressure to prevent excessive supply.

FUEL PUMP CONSTRUCTION

When voltage is applied between the fuel pump terminals, current flows into the solenoid coil which
then pulls up the plunger together with the diaphragm allowing fuel to be drawn into the pump. At this
time, the contact which is linked with the plunger opens and interrupts current causing the coil to be
de-energized. This allows the diaphragm to go down by the spring force, thereby pressurizing and
delivering fuel to the outlet. When the fuel pressure builds up and overcomes the spring force, the
plunger stops at pulled up position with the contact in open position.
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