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

(2) ES-15. MORE THAN ONE HALF OF AGB

b. ACCESSORY GEARBOX (AGB)

AND MAIN OIL PUMP MAGNETIC PLUGS

MAGNETIC PLUG - CONTINUED

ARE COVERED WITH METAL CHIPS.

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

of more than one half of each of the AGB and main oil pump magnetic

plugs being covered with chips. The AGB acts as an oil sump to collect

oil which is scavenged from bearings in the forward engine module and

rear engine subassembly. The main oil pump pumps the hot oil from the

sump to the engine oil cooler. It will be necessary to determine the

source of metal chips on the AGB magnetic plug. Possible sources include

the forward engine module rear engine subassembly, and/or the AGB. 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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