Dry Sealed and Lubricated
Track Joints
Premature dry joints in Caterpillar Sealed
and Lubricated Track may be detected by
any of the following methods:
1. Hand feeling for relatively warm bush-
ings (or pin ends) after the machine has
been operating.
2. Measuring or seeing pitch extended
(internal wear) section of track. Use ultra-
sonic wear indicator to measure internal
wear, if external wear is not visible.
3. Finding bushings significantly more
worn than others in the same track.
No effort should be made to re-lubricate to
restore the joint to lubricated integrity with
new parts in the field once dry enough to
feel heat of friction or measure any internal
wear. This work should be done on the
track press at normal bushing maintenance.
(See separate discussion on Elevated
Sprocket Machines.)
Refer to the individual product sections for
the single joint wear limits.
Wear and Structural
Problems on Sealed and
Lubricated Track Pins
Once dry, the wear pattern and rate on a
Sealed and Lubricated Track pin (and
bushing) should be approximately equal to
the wear on a Sealed Track pin after turn.
For a discussion of those wear patterns, see
the section entitled “SEALED TRACK
PINS & BUSHINGS.”
There are three types of Sealed and Lubri-
cated Track pin wear/structural problems
which may occur in the presence of lubri-
cant and are seen at disassembly or track
separation time because conventional inter-
nal wear has not masked over them.
Pin Galling
CAUSES: Metal-to-metal contact (without
lubrication) between the pin and bushing.
ACCELERATORS: Impact underfoot
conditions, tight track, severe packing, too
wide shoes and lack of lubrication.
EFFECT: Score marks on pin surface. Pin
is reusable for wet or dry turn. This is only
a cosmetic problem which does not result
in track pitch extension like internal wear.
REMEDIES: Eliminate or reduce acceler-
ators (especially tight track and too wide
shoes).
Pin Spalling
CAUSES: Flexing pin causes cracks to
begin in oil reservoir hole and spreads out
to surface at a slow fatigue rate.
ACCELERATORS: Same as “Pin Galling.”
EFFECTS: Chip or flake of material may
become loose from pin surface. Pin should
not be reused for wet or dry turn.
REMEDIES: Same as “Pin Galling.”
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SEALED & LUBRICATED TRACK PINS & BUSHINGS
General Information