TM 9-2815-225-34&P
3-40.
CAMSHAFT CAM FOLLOWER, AND PUSHROD REPAIR (Contd)
LOCATION/ITEM
ACTION
REMARKS
c. Inspection (Contd)
8.
Camshaft (5) (Contd)
c. Inspect for cracks using
Whole surface of camshaft (5) must
magnetic method. Apply 1500
be wetted with magnetic particle
amperes DC longitudinal magnetic
suspension before magnetizing
current for locating open seams
current is applied. Camshaft (5)
and presence of non-metallic
must be magnetized by a single
inclusions. Apply 2000 amperes
shot of current. Disassemble and
DC circular magnetizing current
discard camshaft if not within
for detecting grinding checks.
limits.
(1) Subsurface longitudinal
indications:
None accepted on nose.
Short longitudinal indications up
to 0.625 in. (15.875 mm) long
are acceptable in critical region
on cam surface 0.500 in.
(12.700 mm) before nose and
0.375 in. (9.525 mm) after nose.
Not more than two indications
are allowable in critical region
of any one cam.
Light longitudinal indications
not exceeding two in number
are allowable outside of critical
region.
Parallel indications must be
separated by at least 0.625 in.
(15.875 mm) of metal.
(2) Open longitudinal indications
are not allowable except on base
circle. A maximum of two
longitudinal open indications
0.250 in. (6.350 mm) long or less
will be allowed on base circle
provided they are not closer than
0.250 in. (6.350 mm) and are visible
only as tightly closed lines when
surface is wiped clean. Open
indications shall not be closer than
0.1875 in. (4.763 mm) to edge
of cam (5). Circumferential
indications, lying at an angle
greater than 15° with longitudinal
centerline, are not allowable.
(3) Subsurface longitudinal
indications:
0.125 in. (3.715 mm) indications
are allowable on nose.
Light longitudinal indications up
to 0.500 in. (12.700 mm) are
allowable on ramp.
Not more than two indications
are allowable on ramp or nose
of any one cam (5).
3-192
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