Abstract: A fuel pumping apparatus comprises feed pump supplying fuel to an injection pump. A chamber is located between the two pumps and has an outlet including a restricted orifice extending from the upper end of the chamber through which fuel and air collecting in the chamber can flow. A float is located in the chamber and mounts a valve member which can cooperate with a seating defined about a lower outlet in the lower wall of the chamber. The lower outlet connects with the injection pump and is obstructed if the chamber becomes filled with air to prevent the supply of air to the injection pump.