Fuel sender for motor vehicle

A motor vehicle fuel sender including a container in a fuel tank of the vehicle having a horizontal partition separating a first chamber above the partition from a second chamber below the partition, a one-way valve between the fuel tank and the second chamber permitting only gravity-induced inflow of fuel into the second chamber, a fuel pump having an inlet to the second chamber, a drain port in the horizontal partition, and a float in the second chamber operative to open and close the drain port in accordance with the level of fuel in the second chamber. Return fuel from a motor of the motor vehicle is conducted to the first chamber which is open on top to permit overflow into the fuel tank in a manner which promotes thermal stratification in the fuel tank. The one-way valve is located near the bottom of the fuel tank so that the second chamber is replenished with fuel from only the lowest temperature stratum in the fuel tank. When the one-way valve is starved for fuel and the fuel pump drains the second chamber, the float separates from a lip seal around the drain port to open the drain port.