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

TM 9-2835-255-34

3 - 2 . TROUBLESHOOTING - CONTINUED

a. ACCESSORY GEARBOX (AGB) AND

(5) ES-5. AGB GEAR TRAIN TURNS

UNEVENLY (BINDS) WHEN TURNED BY

HIGH PRESSURE COMPRESSOR -

CONTINUED

HAND AND MORE THAN ONE HALF OF

M A I N OIL PUMP MAGNETIC PLUG IS

C O V E R E D WITH METAL CHIPS.

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

of binding when the AGB gear train is turned by hand, and when more than

one half of the main oil pump magnetic plug is 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 or 4 bearing,

intermediate housing position No. 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 performing troubleshooting.

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