TM 55-2840-254-23
C. During engine operation some air enters the lubrication system. To get rid of this air, a venting system is in-
cluded as part of the lubrication system. It removes air from accessory gearbox assembly and integral oil tank as
follows:
(1)
Accessory gearbox assembly air/oil vapor flows through two external vent lines to starter drive assem-
bly.
(2)
Integral oil tank air/oil vapor flows through negative gravity valve, at top of oil tank, and internally to
starter drive assembly
(3)
Part of gearing in starter drive assembly acts as a centrifuge and separates air from oil. Oil returned to
tank through normal return line. Air vented overboard through tank and engine breather. Helps to keep
oil loss to a minimum.
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