LOW PRESSURE COMPRESSOR RUBS OR BINDS WHEN TURNED BY HAND, RUBBING OR BINDING IS FELT WHEN TUBEAXIAL FAN BLADES OR LEFT COOLING FAN BLADES ARE TURNED BY HAND

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3-2. TROUBLESHOOTING - CONTINUED

h. LOW PRESSURE COMPRESSOR

(6) ES-33.

LOW PRESSURE COMPRESSOR

CONTINUED

RUBS OR BINDS WHEN TURNED BY

H A N D , RUBBING OR BINDING IS FELT

WHEN TUBEAXIAL FAN BLADES OR

L E F T COOLING FAN BLADES ARE

TURNED BY HAND AND MORE THAN ONE

HALF OF THE ACCESSORY GEARBOX

( A G B ) MAGNETIC PLUG IS COVERED

W I T H METAL CHIPS.

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

of low pressure compressor rubbing or binding when turned by hand, when

rubbing or binding is also felt when the tubeaxial fan blades or left

cooling fan blades are turned by hand, and more than one half of the AGB

magnetic plug is covered with metal chips. The low pressure compressor

is mechanically coupled to the low pressure turbine rotor in the rear

engine subassembly.

If there is damage to the low pressure compressor or

position No. 1 or 2 bearing in the forward engine module, or to the low

pressure turbine rotor or position No. 5 bearing in the rear engine

subassembly, binding will be felt when the low pressure compressor is

turned by hand. The power turbine and reduction gearbox (RGB) are

coupled mechanically through the power shaft. If there is damage to the

power turbine,

rear engine subassembly position No. 6A or 6B bearing, or

RGB gearbox bearings and/or gears, bindng will be felt when the

tubeaxial fan blades or left cooling fan blades are turned by hand. 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. The art

on the following pages provides an overview of the systems described

above. Refer to these pages along with in-text art while performing

troubleshooting.

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