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

TM 9-2835-255-34

3-2.TROUBLESHOOTING

CONTINUED

(4) ES-4. 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 MAGNETIC PLUG IS COVERED

W I T H 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 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. 2, 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 forward engine module bearings position number 2, 3,

4 , 11 and 12 gravity scavenge lubricating oil into the AGB. This symptom

indicates that one or more of these bearings has failed or that the AGB

gears and/or bearings have failed. The art on this page provides an

overview of the AGB/high pressure compressor assemblies mechanical and

lubrication system interface. Refer to this page and the in-text art

while performing troubleshooting.

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