Abstract: A fuel supply system for an internal combustion engine is provided. The fuel supply system includes a fuel tank, at least one fuel injector, a fuel supply line and a fuel return line. The fuel supply line is adapted to supply fuel from the fuel tank to the at least one fuel injector. The fuel supply line supplies the fuel via a first pump, a first filter module, a second pump, a second filter module, a third filter module and a third pump. The fuel return line is adapted to return the fuel from the at least one fuel injector to an inlet of the second filter module. The fuel returned from the at least one fuel injector and supplied to the second filter module facilitates in maintaining a consistent back pressure and removing debris from the fuel supply system.

Abstract: A pump for a fuel system is provided. The pump may have a pumping mechanism and an electric motor connected to drive the pumping mechanism. The pump may also have a low-pressure inlet passage in fluid communication with the pumping mechanism, a pressurized inlet passage in fluid communication with the pumping mechanism, a first outlet passage in fluid communication with the pumping mechanism, and a second outlet passage. The pump may further have a valve movable from a first position at which the second outlet passage is blocked from the pumping mechanism, to a second position at which the second outlet passage is in fluid communication with the pumping mechanism.

Abstract: A circuit for a hydraulic pump is provided. The circuit includes a supply of fluid. A pumping element is operable to increase the pressure of fluid received from the supply of fluid and to generate a flow of pressurized fluid. An inlet passageway connects the pumping element with the supply of fluid. A drain passageway is connected to the inlet passageway. A valve is disposed in the drain passageway. The valve is moveable between a first position where the valve prevents a flow of fluid relative to the drain passageway and a second position where the valve allows a flow of fluid relative to the drain passageway.