Abstract: There is provided a hydraulic fuel system having an integrated and internally mounted oil circuit for providing high pressure in a hydraulically operated electronically controlled fuel injector fuel system. There is provide an internally mounted high pressure pump in a pump housing in the crankcase and connected to internally routed high pressure lines that deliver the oil to high pressure oil rails. There is provide an integrated low pressure oil reservoir in the crank case that comprises a low pressure oil cooler and reservoir. The oil cooler is preferably immersed inside the low pressure oil reservoir to optimize available engine space and improve heat transfer. There is also provided a high pressure pump filter that covers a high pressure pump inlet feed passage to prevent debris from passing into the high pressure oil pump and other components on the high pressure oil circuit.

Abstract: There is provided a hydraulic fuel system having an integrated and internally mounted oil circuit for providing high pressure in a hydraulically operated electronically controlled fuel injector fuel system. There is provide an internally mounted high pressure pump in a pump housing in the crankcase and connected to internally routed high pressure lines that deliver the oil to high pressure oil rails. There is provide an integrated low pressure oil reservoir in the crank case that comprises a low pressure oil cooler and reservoir. The oil cooler is preferably immersed inside the low pressure oil reservoir to optimize available engine space and improve heat transfer. There is also provided a high pressure pump filter that covers a high pressure pump inlet feed passage to prevent debris from passing into the high pressure oil pump and other components on the high pressure oil circuit.