TM 5-2410-240-23-1
0004
ENGINE SYSTEMS CONTINUED
Engine Lubrication System
0004
The engine oil pump provides oil pressure for the engine lubrication system. The engine oil pump is located in the
oil pan. The crankshaft drives the oil pump through the idler gear during engine operation.
The pump pulls oil from the oil pan through a strainer. Oil flows from the pump through holes in the cylinder block to
a plate-type oil cooler on the left side of the engine.
From the oil cooler, oil returns through a drilling in the cylinder block to the filter base.
Oil flows from the oil filter through a passage to the oil gallery. The oil gallery is drilled through the total length of the
left side of the cylinder block.
Lubricating oil from the oil gallery flows through passages to the main bearings of the crankshaft. This oil flows
through passages in the crankshaft to the connecting rod bearing journals. The splash of oil and oil mist lubricate
pistons and cylinder bores.
Lubricating oil from the main bearings flows through passages in the cylinder block to the journals of the camshaft.
Then, the oil flows from the second journal of the camshaft at a reduced pressure to the cylinder head. The oil then
flows into the rocker arm bushing of the rocker arm levers. The splash of oil and oil mist lubricate the valve stems,
valve springs, and valve lifters.
Oil from the oil gallery lubricates the hub of the idler gear. The splash of oil lubricates the timing gears.
Each cylinder has a piston cooling jet installed in the cylinder block. The jets cool the pistons by spraying engine oil
onto the inner surface of the piston.
Lubricating oil for the turbocharger flows through a drilled passage in the cylinder block. An external line from the
engine block supplies oil to the turbocharger. The oil then flows through a line to the oil pan.
END OF WORK PACKAGE
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