Isuzu AA-6HK1T, Workshop Manual

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6G–2 ENGINE LUBRICATION
General Description
Lubricating Oil Flow
The engine uses a pressure-feed lubrication system.
Oil flows from the oil pump to the oil filter for cleaning. It
then travels to the oil cooler where it is cooled.
From the oil cooler, the oil moves to the cylinder block oil
gallery for distribution to the moving parts of the engine.
Oil jets are arranged in a line near the center of the
cylinder block oil gallery. The oil jets spray oil to the
inside portions of the pistons to provide the most
effective lubrication and cooling.
Oil Pump and Oil Filter
The gear-type oil pump is driven by the timing gear. The
pump is equipped with a relief valve.
The full-flow oil filter uses a highly-efficient paper
element.
If the element becomes clogged, the by-pass valve
opens to route the oil directly to the oil gallery. A warning
lamp turns on to warn the equipment operator that the oil
filter is being bypassed.
Oil cooler
Engine oil temperature rises with engine temperature
with a corresponding decrease in lubricating
efficiency.The oil cooler consists of the body and the
cooling element.
The oil cooler maintains oil temperature at the level
required for optimum engine lubrication.