ENGINE FUEL SUPPLY CIRCUIT

A fuel supply circuit for a Diesel engine includes fuel injectors, a fuel tank, a main pump for delivering fuel to the injectors, and a variable flow charge pump for delivering fuel from the tank to an inlet of the main pump, and a surplus fuel line communicating unburned fuel from the injectors to an inlet of the charge pump. The circuit also includes a temperature sensor which senses a temperature of fuel discharged by the charge pump, and a pressure sensor which senses a pressure of fuel discharged by the charge pump. A bleed line communicates fuel from an outlet of the charge pump to the tank. A solenoid operated bleed valve and a pressure relief valve control flow through the bleed line. An electronic control unit controls the charge pump and the bleed valve as a function of the sensed parameters.