Abstract: A closed feeding system for liquid fuel includes a flexible tube (1) extending from a reservoir (7) to a strainer housing (8) for differential pressure feeding of fuel, provided with pump assembly (3), in which system there is disposed a second, flexible tube (2) for return of fuel to the reservoir (7), the feed tube upstream and downstream of the pump assembly (3) being provided with non-return valves (4'-5') for flowing toward the strainer housing (8) and the return tube (2) optionally being provided with a non-return valve (6') for flowing toward the reservoir.