TM 55-2840-241-23
CHAPTER 5
ACCESSORIES SERVICING
Section 1. GENERAL
5-1. Scope.
This section is intended to be used by Aviation Unit
and Aviation Intermediate Maintenance personnel to
perform accessories maintenance with maximum effi-
ciency. Maintenance functions are grouped into sec-
tions by systems. Each section includes detailed
instructions for removal, installation, adjustment,
lubrication, and minor servicing of the individual com-
ponents of the system.
5-2. General Practices and Precautions.
When performing maintenance on the engine. the
following practices and precautions must be observed.
Prolonged contact with lubricating oil,
(item 7, table 2-2) may cause a skin rash.
Those areas of skin and clothing that come
into contact with lubricating oil should be
thoroughly washed immediately. Areas in
which lubricating oil is used should be
adequately ventilated to keep mist and
fumes to a minimum.
N O T
E
Lubricating oil may soften paint upon contact. If
lubricating oil is spilled on painted surfaces. these
surfaces should be thoroughly washed.
a. Protect engine from dust and inclement weather.
When possible, perform maintenance
in a sheltered
area.
b. On removal of engine components, exercise care
to prevent dirt and other foreign matter from entering
the engine. Caps, plugs, or temporary covers shall be
used to close all openings. Do not use tape to cover fuel
and oil openings. Tape adhesive is soluble in fuel or oil
and can cause contamination.
c. When the gas producer fuel control power tur-
bine governor, check valve, or accumulator are
removed from the engine, use extreme care to prevent
foreign materials from entering the pneumatic lines or
the ports of the components.
d. Always use a backup wrench on fittings when
removing or installing tubing.
e. Before removing ignition components. discon-
nect the input power lead at the ignition exciter.
f. C a r e f u l l y i n s p e c t t h e c o n d i t i o n o f a l
replacement parts before installation.
g. Never attempt to rotate the gear trains and
rotors using a speed wrench at the tachometer drive
pads. Side loads on the speed wrench could crack the
tachometer drive shaft. Rotate the gas producer gear
train and rotor using the 6799790 turning adapter at
the fuel control, fuel pump. starter generator, or spare
accessory drive pad. Rotate the power turbine gear
train and rotor using the 6799790 turning adapter at
the power turbine governor drive pad.
5-3. Hardware.
Use 0.020 in. diameter stainless steel lockwire (item
10, table 2-2 where lockwire size is not specified. Dou-
ble strand lockwire all drilled bolts, plugs, and screws.
except those locked with self-locking nuts or lock-
washers. Lockwire bolts in pairs where possible. When
reassembling, be sure to safety wherever lockwire was
removed.
To prevent possible failure, do not use zinc
lockwire. Do not reuse lockwire, cotter
pins, ring seals, lip seals, composition gas-
kets, and split or tab washers.
Change
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5-1
