Lubrication System - Oil Circulation Circuit

Engine Oil Circulation Diagram 1 – cylinder head oil gallery 2 – main oil gallery 3 – piston cooling oil jet 4 – main flow oil filter 5 – oil cooler

The engines are equipped with a pressure lubrication system. The oil pump draws engine oil from the oil pan through a strainer and delivers it under pressure through the oil filter. A pressure relief valve is located on the discharge side of the oil pump. When oil pressure is excessive, the valve opens and part of the oil returns to the oil pan.

Filtered oil flows through the central part of the filter element into the main oil gallery. The oil pressure sensor is located there, which indicates insufficient oil pressure to the driver through a warning lamp in the instrument cluster. If the oil filter becomes clogged, the bypass valve directs oil without filtration directly into the main oil gallery.

Lubrication channels for the crankshaft bearings branch off from the main oil gallery. Oil passes through inclined passages in the crankshaft to the connecting rod bearings. Piston crown cooling is performed by oil jets that spray oil upward into the piston from below.

Simultaneously, engine oil passes through vertical lines into the cylinder head, supplying oil to the camshaft bearings and hydraulic valve lash adjusters.

Depending on the version, the oil is cooled by a radiator located on the oil filter flange and connected to the engine cooling system.

Oil consumption

Oil consumption refers to the amount of oil that is burned during combustion. It must in no way be understood as oil loss due to leaks through the oil pan, cylinder head cover, etc.

Normal oil consumption results from the burning of small amounts of oil in the cylinders, together with exhaust gases, and from wear. Oil is also lost due to the high temperature and high pressure present in the engine. Operating conditions, such as driving style, and manufacturing tolerances of engine components also affect oil consumption. Oil consumption must not exceed 1 L/1000 km.

CAUTION

Never fill oil above the Max mark. If oil has been overfilled, the excess must be removed by suction. Otherwise, unburned oil entering the catalytic converter may damage it.