MD Helicopters CSP-900RMM-2, Servicing And Maintenance

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CSP − 900RMM − 2 MD Helicopters, Inc.
Rotorcraft Maintenance Manual
Page 605
Revision 29
63-20-00
B. Acoustic Isolator Inspection
(1). Examine acoustic isolator for too much
elastomeric material out from between
static mast support and transmission.
No damage permitted.
(2). Examine external surfaces of acoustic
isolator for cracks or delamination. No
damage permitted.
NOTE:
Loose bolts can be an indication of wear
or deterioration of acoustic isolator.
(3). Examine bolts that attach transmission
to mast base for correct installation. No
incorrect installation permitted.
C. Chip Detector Inspection
NOTE:
For more aid, speak to your local MDHI
Field Service Representative.
The components of the transmission are made
of different materials. You can find which
component(s) made the metal particles when
you have an Energy Dispersive X-ray Spec­
troscopy, or equivalent test, done.
Operator removable bearings are made of
52100. These are the hydraulic pump, cooling
blower, notar, input, lube pump, and clutch
bearings. Some of these can be replaced
without removal of the transmission.
Bearings operators can not remove are made
of M50 or CBS-600 (Japanese equivalents).
M50 metal particles are from Planetary
bearings and CBS-600 metal particles are
from tapered roller bearings. If you get these
metal particles, it is necessary to overhaul
transmission.
Other metals in transmission are 4340
clutches and 4130 lock nuts.
Metal particles can be found on chip detector
when transmission
CHIPS caution message is
shown on Integrated Instrument Display
System (IIDS) or during usual maintenance. If
there are metal particles, it is not necessarily
an indication transmission is unserviceable.
But, the type and quantity of metal particles
found can be an indication there is a defective
transmission component.
(1). Remove chip detector and screen/valve
(housing) assembly.
(2). Examine chip detector and housing for
metal particles (Ref. Table 601).
(3). Make sure chip detector and housing
are clean of all particles.
(4). Install screen/valve (housing) assembly
and chip detector.
Table 601. Metal Particle Inspection
Material Quantity/Size Probable Cause Corrective Action Ref. Section
Magnetic Fuzz or fine hair − like
particles (one or two
particles)
0.02 x 0.14
inches (.51 x 3.56 mm)
long.
Result of normal wear.
Clean off chip detector
and housing and perform
chip detector test.
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Inspect filter impending
bypass (pop − up)
indicator
Multiple (heavy) deposits
of chips greater than
0.06 inch (1.52 mm)
in
diameter.
Impending failure of an
internal component.
Perform transmission
serviceability test.
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Chips larger than
0.08 x 0.14 inches
(2.03 x 3.56 mm)
Internal component
failure.
Replace transmission. 63 − 20 − 00
Nonmagnetic Heavy deposits on
nonmagnetic particles.
May have resulted during
assembly.
Perform transmission
serviceability test.
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