Design features of the lubrication system

The lubrication system is combined: the most loaded parts are lubricated under pressure, while the rest are lubricated either by directed spraying or spraying of oil flowing from the gaps between the mating parts. The lubrication system is pressurized by a gear oil pump mounted externally at the front of the cylinder block and driven from the front end of the crankshaft. The pump is made with internal trochoidal gearing.

The pump sucks oil from the engine oil sump through an oil receiver with a strainer and delivers it through a full-flow oil filter with a porous paper filter element to the main oil line located in the body of the cylinder block. Oil supply channels to the main bearings of the crankshaft depart from the main line. Oil is supplied to the connecting rod bearings through channels made in the body of the crankshaft. A vertical channel for supplying oil to the camshaft bearings departs from the main oil line. In addition, from the main oil line of the engine, oil is supplied under pressure to the variable valve timing system, equipped with a separate filter installed in the cylinder head. The filter of the variable valve timing system is bypass type, i.e. under any conditions, ensures the supply of oil to the variable valve timing system.

To lubricate the camshaft bearings, oil from the vertical channel enters the central axial channels of the camshafts through a radial hole in the neck of one of the bearings and is distributed through them to the rest of the bearings.

The camshaft cams are lubricated with oil coming from the central axial channels through the radial holes in the cams. Excess oil is drained from the head of the block into the oil sump through vertical drainage channels.

Changing the engine oil and oil filter is described in Sec. 4 «Maintenance» (cm. «Changing engine oil and oil filter»), removal and installation of the oil pump are discussed in the next subsection.