Provided is a V engine which uses common cylinder heads, and permits favorable arrangement of oil passages so as to accommodate various oil regulating features that are required to operate valve property varying mechanisms. Each end of each cylinder head is formed with a plurality of distribution oil passages opening out at an upper surface of the cylinder head for supplying oil pressure from a main gallery to a valve actuating mechanism. A pair of oil passage connecting members internally defining mutually different connecting oil passages are attached to the upper surfaces of the corresponding end parts of the respective cylinder heads.

To provide a chain guide assembly frame capable of efficiently collecting the oil that adhered to various parts of the chain guide assembly, and guiding the collected oil to predetermined locations, to allow efficient use of oil, with a simple structure. The chain guide assembly frame includes driven sprocket holding portions, a fixed chain guide, and a pivoting chain guide holding portion on a main body. A drive sprocket holding portion is provided at a position lower than the driven sprocket holding portions. The main body includes a concave and/or convex oil passage that extends from an upper part toward a lower part to guide the oil toward above the drive sprocket holding portion.

A cylinder block has a different amount of oil supply for each journal, in which a plurality of bearing saddles are arranged at intervals and main bearings, which support main journals of a crank shaft, are respectively mounted to the plurality of bearing saddles. The bearing saddles comprise oil galleries formed in the cylinder block. Oil chambers are recessed from surfaces of the plurality of bearing saddles, to which an oil is supplied through the oil galleries, and communicate with end portions of the oil galleries to store the oil supplied from the oil galleries. The main bearings have oil holes through which the oil introduced into the oil chambers flow to the main journals. The amount of oil supplied to the main journals is determined according to an overlapped amount between the oil chambers and the oil holes.

A cylinder block has a different amount of oil supply for each journal, in which a plurality of bearing saddles are arranged at intervals and main bearings, which support main journals of a crank shaft, are respectively mounted to the plurality of bearing saddles. The bearing saddles comprise oil galleries formed in the cylinder block. Oil chambers are recessed from surfaces of the plurality of bearing saddles, to which an oil is supplied through the oil galleries, and communicate with end portions of the oil galleries to store the oil supplied from the oil galleries. The main bearings have oil holes through which the oil introduced into the oil chambers flow to the main journals. The amount of oil supplied to the main journals is determined according to an overlapped amount between the oil chambers and the oil holes.

An adapter replaces a crankcase screw-on oil filter for an internal combustion engine and couples pressurized oil in the engine's crankcase with at least one external component. The adapter includes a valve that prevents backflow of oil from the external component to the crankcase.

An adapter replaces a crankcase screw-on oil filter for an internal combustion engine and couples pressurized oil in the engine's crankcase with at least one external component. The adapter includes a valve that prevents backflow of oil from the external component to the crankcase.

A lubrication system in an internal combustion engine is provided. The lubrication system includes a crankshaft bearing supporting a crankshaft, a supply line including an outlet flowing oil to the crankshaft bearing and an inlet receiving oil from an oil gallery, and thermal insulation at least partially surrounding at least a portion of an inner wall of the supply line and/or the oil gallery.

A lubrication system in an internal combustion engine is provided. The lubrication system includes a crankshaft bearing supporting a crankshaft, a supply line including an outlet flowing oil to the crankshaft bearing and an inlet receiving oil from an oil gallery, and thermal insulation at least partially surrounding at least a portion of an inner wall of the supply line and/or the oil gallery.

An internal combustion engine, includes a turbocharger with a variable geometry turbine having an actuator shaft passing through the turbocharger housing. The actuator shaft opening is vented to the engine crankcase for diverting exhaust that passes through the actuator shaft opening to the crankcase instead of being released to the under-hood environment.

An internal combustion engine, includes a turbocharger with a variable geometry turbine having an actuator shaft passing through the turbocharger housing. The actuator shaft opening is vented to the engine crankcase for diverting exhaust that passes through the actuator shaft opening to the crankcase instead of being released to the under-hood environment.