Tank system with an ejector pump

The system has a fuel tank storing a fuel i.e. diesel fuel, for operating a combustion engine i.e. diesel engine (17), where the fuel tank is formed as an auxiliary tank (19). A suction jet pump conveys the fuel from the auxiliary tank into a main tank (18) such that the combustion engine is supplied with the fuel through a flow line (20) from the main tank. A tank transmitter (21) measures a level of fuel in the fuel tanks, where the suction jet pump is structurally integrated into the tank transmitter. A return-flow pipe (24) recirculates unused fuel from the combustion engine.