Apparatus for supplying a fuel by means of a fuel supply unit arranged in a housing

The apparatus for supplying fuel includes a fuel tank and a fuel feed unit in the fuel tank. The fuel feed unit has a main housing, a suction cover arranged in a bottom part of the main housing, a fuel pump and a degassing valve arranged in the suction cover for degassing the fuel pump. The fuel pump itself includes an impeller housing with a circular passage for fuel flow and an electric-motor-driven impeller. The impeller housing is arranged in the main housing and next to the suction cover and it is provided with a degassing passage connecting the circular passage with the degassing valve. To improve starting behavior the fuel feed unit has a degassing valve in the suction cover, which is connected with the circular passage of the impeller housing by a degassing passage. The degassing valve opens to the fuel tank when pressure in the degassing passage exceeds a predetermined value for degassing the fuel pump. The degassing valve can be a spring-loaded ball valve in which the compression spring bearing on the ball provides a predetermined counter-force so that the degassing valve is kept open during idle and start of impeller rotation until degassing is complete.