Engine Lubrication: Description and Operation

DESCRIPTION
The engine lubrication system is designed to provide optimum oil flow to critical components of the engine throughout its entire operating range.

OPERATION
1. Oil is drawn into the oil pump (6600) through the oil pump screen cover and tube (6622) in the sump.
2. Oil is pumped through the oil bypass filter (6714) on the left front side of the cylinder block (6010).
3. Oil enters the main oil gallery where it is distributed to the crankshaft main journals, and to both cylinder heads (6049).
4. From the crankshaft main journals, the oil is routed through cross-drilled passages in the crankshaft (6303) to the crankpins for connecting rod bearing lubrication.
5. Controlled leakage through the crankshaft main bearings (6333) and connecting rod bearings (6211) is distributed radially outward to cool and lubricate the cylinder walls as well as the entire connecting rod (6200), piston (6108) and piston ring assemblies.

CYLINDER HEAD
The left cylinder head is fed from a drilling into the lateral supply passage feeding the main gallery at the front of the cylinder block.
The right cylinder head is fed from a drilling into the rear of the main gallery.

PRESSURE
Main gallery pressure is reduced as it enters the cylinder head galleries through the use of fixed serviceable orifices located at the upper part of the feed passages. This reduced pressure in the cylinder head galleries feeds the following:
^ Camshaft journals.
^ Valve tappets (6500).
^ Hydraulic timing chain tensioners (6L266).
^ Cam lobes and rocker arms (6564) (lubricated by splash created through valve train operation).