Gasoline water pump driven by variations in the road, tend to be separated into mechanical and electrical drive diaphragm driven two. Mechanically driven diaphragm type fuel pump generally believe in the eccentric cam shaft drive, its tasks are:
 oil camshaft rotation, in case the eccentric wheel shake the important arm, pull the pump rod membrane, the membrane pump down, causing suction, suction tank of gasoline begins, and thru the tubing, fuel filter, fuel pump oil onto the room.
 When eccentric rotary pump oil tremendous will no longer be shake the arm angle, the pump membrane spring done, move some of the best membrane power up the gas valve inside the oil pressure to the carburetor float chamber.
Usually the largest oil gasoline water pump maximum fuel consumption than the gasoline engine 2.5 to a few.Five times. Whenever the fuel pump and fuel consumption is more than the carburetor float chamber needle valve closed, pump out the oil pipeline from the pressure increased, the reaction into the pump, the diaphragm shortened trip or stop working.
A different type of electric fuel pump, you shouldn't believe the camshaft drive, and repeated by electromagnetic force pump suction action film. This electric pump, the freedom to decide on the installation location, to prevent vapor lock phenomenon.
Electronically controlled fuel injection system fuel pump, generally work with a new model of electric pump impeller and running on the gas chamber, gasoline engine the pumping pressure n comparison to the carburetor fuel supply system, gasoline water pump high.