Engine Lubrication: Description and Operation

Oil is drawn from the reservoir in the oil pan and pressurized by the oil pump. The output from the oil pump is then filtered and distributed through the internal oil passages.
Where an oil cooler is installed, the oil is cooled before entering the filter.
All moving parts are lubricated either by pressure or splash oil. Pressurized oil is also provided for operation of the variable valve timing units and the timing gear chain tensioners.
With the exception of the pump and the oil level gauge (dip stick), all of the oil system components are installed on the structural sump.
Oil is returned to the oil pan under gravity through large drain holes in the cylinder heads and the engine block to ensure quick return of the oil.