Cars use a pressure lubrication system for the engine. Oil from the oil pan is supplied under pressure by an oil pump through a strainer and a fine filter. The oil pump is driven by a chain from the crankshaft. The bypass valve in the oil pump maintains the required pressure in the engine lubrication system. If the pressure in the engine lubrication system exceeds a certain level, the bypass valve opens and some of the oil flows back into the oil pan.
Passing through the oil filter, the purified oil enters the main oil line. It is equipped with an emergency oil pressure drop sensor, which, turning on the warning lamp in the instrument cluster, signals low oil pressure. The oil filter has a bypass valve, through which, in the event of severe contamination of the filter, unrefined oil flows directly into the oil line. From the main line, oil under pressure is supplied through channels to lubricate the main bearings of the crankshaft and then through channels in the crankshaft to the connecting rod bearings.
Oil is supplied through the channels to the cylinder head to lubricate the camshaft bearings.