TM 55-2840-254-23
D.
Oil flow through the engine lubrication system is as follows:
Oil leaves integral oil tank through bottom of inlet housing and flows through an external line to main oil
(1)
pump.
Oil from pump pressure element flows through the main oil fitter, past temperature transmitter, through
(2)
the check valve and oil cooler assembly. The main oil pump, filter and cooler assembly each contain
bypass valves.
Two flow paths leave oil cooler assembly. One path flows oil to rear of engine to lubricate No. 2 and
(3)
No. 4 and 5 bearings. Second flow path directs oil to front of engine to lubricate accessory drive gears
and bearings, starter drive gears and bearings, and No. 1, 3, 6 and 7 bearings.
Oil flows through a filter to No. 2 bearing, through dual chip detector and to accessory gearbox assem-
(4)
bly.
Oil flows through a filter to No. 4 and 5 bearings, through scavenge element in main oil pump. through
(5)
dual chip detector, and to accessory gearbox assembly.
Oil leaving accessory drive gears and bearings and the No. 1, 3, 6, and 7 bearings flows through inter-
(6)
nal paths to accessory gearbox assembly.
Oil leaves accessory gearbox assembly through a strainer and main scavenge element in main oil
(7)
pump and returns to inlet housing.
Oil flow in inlet housing is through two passages that surround the integral oil tank. As passages are
(8)
located in inner diameter of inlet housing next to inlet air passage, heat transfer takes place. Inlet air is
heated (desired) and oil temperature lowered. Oil flow then reenters oil tank.
Oil entering starter drive gears and bearings is filtered and flows directly to integral oil tank filler tube
(9)
and into tank.
(10) Oil is removed from integral oil tank by opening drain cock
Change 10
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