Fuel Pump: Description and Operation

Fuel pump, cars with a catalytic converter (-1988)





The fuel pump (1), housed in a container (2) inside the fuel tank, is an electric rotary pump. The pump and rotor are factory-sealed and cannot be dismantled for overhaul or repair. The pump incorporates a relief valve which opens if the pressure exceeds a preset limit. A non-return valve in the feed line from the pump prevents the pressure from dropping immediately after the pump has stopped running.

An electric feed pump (3) supplies the container with fuel from the tank. The container acts as a pressure vessel and, since the main fuel pump is always supplied with fuel under pressure, this prevents the formation of vapor locks.