Gasoline water pump driven by differences in the way, can be divided into mechanical and electrical drive diaphragm driven two. Mechanically driven diaphragm type fuel pump generally rely on the eccentric cam shaft drive, its work is:
　　① oil camshaft rotation, when the eccentric wheel shake the top arm, pull the pump rod membrane, the membrane pump down, resulting in suction, suction tank of gasoline begins, and through the tubing, fuel filter, fuel pump oil into the room.
　　② When the eccentric rotary pump oil over the top is no longer shake the arm angle, the pump membrane spring done, move the top membrane pump up the gas valve from the oil pressure to the carburetor float chamber.
　　Generally the largest oil gasoline water pump maximum fuel consumption than the gasoline engine 2.5 to 3.5 times. When the fuel pump and fuel consumption is greater than the carburetor float chamber needle valve closed, pump out the oil pipeline in the pressure increased, the reaction to the pump, the diaphragm shortened trip or stop working.
　　Another kind of electric fuel pump, do not rely on the camshaft drive, and repeated by the electromagnetic force pump suction action film. This electric pump, the freedom to choose the installation location, and to prevent vapor lock phenomenon.
　　Electronically controlled fuel injection system fuel pump, generally use a new type of electric pump impeller and installed in the gas chamber, the pumping pressure than the carburetor fuel supply system, gasoline water pump high.