TM 55-1520-240-23-9
11-9
INSPECT BELLCRANK AND CONNECTING LINK BEARINGS (INSTALLED)
(Continued)
11-9
d.
Unserviceable bearings are those which have
one or more of the following discrepancies:
(1)
Fractured Components. Replace all
bearings with cracked or broken rings,
retainers, or rolling elements.
(2)
Frozen Bearings. Replace all bearings
that are frozen and cannot be rotated.
(3)
Damaged Seals and Shields. Replace
bearings if seals and shields are
damaged, warped, or bent.
(4)
Rough Bearings. Replace any bearings
that has any obvious catching or binding
when rotated by hand. Roughness may
be caused by caked or deteriorated
grease, foreign particles, corrosion,
brinelling from improper installation,
spalling of the rolling elements from
metal fatigue. The latter three causes
of roughness can be corrected only by
replacement of the bearing. The first two
causes may be corrected by cleaning and
re-lubrication.
(5)
Loose Bearings. Replace the bearing
if looseness is detected in either axial
or radial play. Refer to the appropriate
maintenance manual for allowable limits.
(6)
Noisy Bearings. Noisy bearings usually
indicate a lack of lubricant. Return
the bearings to service if lubrication
alleviates the problem. Replace the
bearing if re-lubrication does not correct
the problem.
(7)
Corroded Bearings. Excessive external
corrosion frequently indicated that the
interior may be corroded. Replace the
bearing.
(8)
Caked or Deteriorated Grease. Damage
to bearings may result from lack of
lubricant, caked or deteriorated grease.
Replace the bearing if lubrication does
not correct the problem.
(9)
Rod Ends. When rod ends are inspected,
the threaded portion of the shank should
be examined for damaged threads or
looseness between the shank and the
linkage or rod, and fretting abrasion or
wear. Check for cracks in the thin section
of the housing adjoining the shank.
Replace the rod end bearing for any of the
above inspection. The above inspection
is accomplished without removing rod
end from flight control rod.
NOTE
Rod end bearings may have either
of two types of integral lubrication
provisions (grease fittings):
NO BREAK - WORK HARDER
a.
Red Nylon Type
b.
NAS516-1A Ball Check Type
NO BREAK - WORK HARDER
The nozzle to be used for lubricating
the bearing is either MS24203 nozzle
or Alemite nozzle 314150.
DRY TYPE BEARING
2.
Check dry type rod end bearing as follows:
a.
Repeat step 1. If radial looseness is more
than 0.007 inch, remove link and perform
Task 11-8.
b.
Push bearing to one side of bellcrank.
Measure distance between bearing and lug
of bellcrank.
c.
Push bearing to other side of bellcrank.
Measure distance between bearing and
same lug of bellcrank used in step b.
d.
Subtract step b distance from step c distance.
If difference is more than 0.01 inch, remove
link and perform Task 11-8.
11-43
