A seal structure between an oil outlet formed in a first case and an oil inlet formed in a second case and having an end face facing an end face of the oil outlet with a clearance between the end faces, the seal structure including an annular first seal disposed in an increased-diameter hole, which is formed on an outlet side or an inlet side of an oil passage in one of the oil outlet and the oil inlet and has a larger diameter than the oil passage, such that the first seal contacts a step surface located at a boundary between the oil passage and the increased-diameter hole; and an annular second seal harder than the first seal and disposed in the increased-diameter hole such that the second seal contacts the first seal and the end face of the other of the oil outlet and the oil inlet.

An internal combustion engine includes a one-piece cylinder block casting, a flywheel supported for rotation at a front block end, and a back gear train supported for rotation at a back block end. Cast-in pump inlet and outlet passages are formed in the cylinder block casting and open in a pump mounting face at the back block end. An oil pump is clamped to the pump mounting face and includes a pump inlet and a pump outlet fluidly connected, respectively, to the cast-in pump inlet passage and the cast-in pump outlet passage.

An internal combustion engine includes a one-piece cylinder block casting, a flywheel supported for rotation at a front block end, and a back gear train supported for rotation at a back block end. Cast-in pump inlet and outlet passages are formed in the cylinder block casting and open in a pump mounting face at the back block end. An oil pump is clamped to the pump mounting face and includes a pump inlet and a pump outlet fluidly connected, respectively, to the cast-in pump inlet passage and the cast-in pump outlet passage.

An electric oil pump includes a motor part having a shaft; a pump part that is driven by the motor part via the shaft and discharges oil; and a control part configured to control an operation of the motor part. The motor part includes a rotor, a stator, and a motor housing in which the rotor and the stator are accommodated. The pump part includes a pump rotor attached to the shaft and a pump housing having a housing part in which the pump rotor is accommodated. The control part includes an electronic component and a board having a surface on which the electronic component is mounted. The board is disposed outside the stator in a radial direction and within a range of the motor part in the axial direction, and the surface of the board is disposed to face the stator and extends in the axial direction.

A pump, wherein a first pressure space and a second pressure space are formed between an end-facing wall of an accommodating housing and a second housing part of a pump insert, wherein an annular sealing element which is arranged between the end-facing wall and the second housing part encloses the second pressure space and seals it off in relation to the first pressure space, wherein the first pressure space is connected via a first outlet channel to a first delivery chamber which is formed between a rotor and a stroke ring of the pump insert, and the second pressure space is connected via a second outlet channel to a second delivery chamber which is formed between the rotor and the stroke ring.

An internal combustion engine assembly includes a crankcase and a cam housing. The crankcase includes a crankcase cavity configured to receive a counterweight. The cam housing includes a cam housing cavity configured to receive a camshaft. A pump is positioned within the cam housing. The pump is configured to draw oil from an oil reservoir defined by the cam housing cavity. A crankshaft supports the counterweight for rotation therewith. The crankshaft is rotatably supported within the cam housing and is coupled to drive the pump. A bearing supports the crankshaft between the crankcase cavity and the cam housing cavity. The bearing includes an outer race. A seal is positioned between the pump and the bearing. The seal is positioned against the outer race to block the transmission of pressure fluctuations between the crankcase cavity and the oil reservoir.

System and methods mount an accessory to an engine block having a pilot bore aligned with a first plane and sealing surfaces aligned to a second plane different than the first plane. The accessory includes a sliding pilot for interfacing with the pilot bore that is capable of sliding in an x direction yet fixed in a y direction with respect to the accessory housing. Interfacing the sliding pilot in a mounting position with the pilot bore along a z direction locates the accessory with respect to the engine block in the y and z directions. Fastening the accessory to the sealing surfaces of the engine block locates the accessory in the x direction with sufficient precision to mitigate gear backlashing and providing one or more fluid seals between the accessory and the engine block.

An oil pump includes a housing defining a pump cavity having an inner circumferential wall with a first segment located in a low-pressure side of the pump cavity. The first segment defines a recessed cutout. A gerotor pump set is disposed in the cavity and includes an inner drive rotor and an outer driven annulus. An outer circumferential wall of the outer annulus and the cutout cooperate to form an increased radial clearance to reduce friction losses between the outer annulus and the housing.

An engine oil strainer includes a lubricating oil passage, and an oil inlet and an oil outlet which are respectively disposed at two ends of the lubricating oil passage. The engine oil strainer further includes a check valve which is disposed at the oil inlet and which only allows a lubricating oil to flow into the lubricating oil passage. Also disclosed herein are a lubrication system employing the engine oil strainer, and an internal combustion engine having the lubrication system. When the internal combustion engine stops operating, the lubricating oil flows back from the oil outlet into the engine oil strainer. Since the check valve is disposed at the location of the oil inlet of the engine oil strainer, the lubricating oil flowing back into the engine oil strainer is not capable of proceeding to flow back from the oil inlet into the oil pan.

An internal combustion engine assembly includes a crankcase and a cam housing. The crankcase includes a crankcase cavity configured to receive a counterweight. The cam housing includes a cam housing cavity configured to receive a camshaft. A pump is positioned within the cam housing. The pump is configured to draw oil from an oil reservoir defined by the cam housing cavity. A crankshaft supports the counterweight for rotation therewith. The crankshaft is rotatably supported within the cam housing and is coupled to drive the pump. A bearing supports the crankshaft between the crankcase cavity and the cam housing cavity. The bearing includes an outer race. A seal is positioned between the pump and the bearing. The seal is positioned against the outer race to block the transmission of pressure fluctuations between the crankcase cavity and the oil reservoir.