Page 87 - The Jet Engine

Lubrication

second shot to be delivered to the rear bearing only, oil then drains overboard through a central tube in
after a predetermined period. the exhaust unit inner cone.
11. After lubricating the fuel unit and front bearings, OIL SYSTEM COMPONENTS
the oil from the front bearing drains into a collector 12. The oil tank (fig. 8-4) is usually mounted on the
tray and is then ejected into the main gas stream engine and is normally a separate unit although it
through an ejector nozzle. The oil that has passed may also be an integral part of the external gearbox.
through the rear bearing, drains into a reservoir at It must have provision to allow the lubrication system
the rear of the bearing where it is retained by to be drained and replenished. A sight glass or a
centrifugal force until the engine is shut down. This dipstick must also be incorporated to allow the oil

Fig. 8-4 An oil tank.

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