Engine Lubrication: Description and Operation

Lubrication system
The oil is led from the oil pan via a suction nozzle to the oil pump. The oil pump is located on the engine block. The oil is then pumped onwards to the oil cooling system and then to the oil filter. The oil flows from the filter through a cast oil duct in the intermediate section to the main bearings. The oil then flows through bored channels in the crankshaft to the connecting rod bearings.

The camshafts are supplied with oil by a bored channel in the cylinder block. The channel runs through the cylinder head, where it flows out at the bottom of the upper half of the cylinder head. There is a cross duct in the channel to the cylinder head which carries oil to the pistons via a piston cooling valve.

The oil flows on via an oil duct to the bearing for the lefthand camshaft and the valve lifters (intake side). The bearings for the righthand side camshaft (exhaust side) are supplied by a cast cross duct at the front edge of the upper half. This cast cross duct also supplies pressurized oil to the solenoids for the VVT unit. Drain holes in the cylinder block release the oil from the cylinder head and crankshaft bearing back to the oil pan.