AGB GEAR TRAIN TURNS UNEVENLY (BINDS) WHEN TURNED BY HAND AND MORE THAN ONE HALF OF AGB AND MAIN OIL PUMP MAGNETIC PLUGS ARE COVERED WITH METAL CHIPS.

TM 9-2835-255-34

3-2. TROUBLESHOOTING - CONTINUED

(11) ES-11. AGB GEAR TRAIN TURNS

a. ACCESSORY GEARBOX (AGB) AND

UNEVENLY (BINDS) WHEN TURNED BY

HIGH PRESSURE COMPRESSOR -

HAND AND MORE THAN ONE HALF' OF

CONTINUED

AGB AND MAIN OIL PUMP MAGNETIC

PLUGS ARE COVERED WITH METAL

CHIPS.

This section contains troubleshooting to locate and correct the cause(s)

of binding in the AGB gear train when turned by hand, when more than one

half of the AGB and main oil pump magnetic plugs are covered with metal

chips. The AGB is coupled to the high pressure compressor in the forward

engine module through a gearshaft. If there is damage to the high

pressure compressor, forward engine module position No. 3, 4, 11 or 12

bearing, or AGB gears and/or bearings, binding will be felt when the AGB

gear train is turned by hand. The reduction gearbox (RGB) oil return

line feeds directly into the oil pump passage that houses the magnetic

plug. The only possible source of metal chips on the oil pump magnetic

plug is the RGB. These two systems are totally independent of each

other. The symptoms described above indicate two separate failures. The

art on this page provides an overview of the systems described above.

Refer to this page along with in-text art while doing troubleshooting.

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