Great Plains NTA3007 Operator Manual - Manual (Page 147)

Great Plains Manufacturing, Inc. Table of Contents Index Maintenance and Lubrication 143
2012-07-02 Table of Contents Index 166-371M
Brake Drum Maintenance
Refer to Figure 151
45. Inspect the shoe surface (the inside rim). Normal
appearance is dull gray, with no more than light
scoring and light wear.
One or two light score marks are not cause for
resurfacing or replacement. If there are any
questions concerning the condition of a drum,
consult an expert.
Replace or resurface a drum that is heavily scored,
worn to more than 0.51 mm (0.020 inch) oversize, or
has 0.38 mm (0.015 inch) or greater run-out.
Brake Drum Resurfacing
46. A standard drum lathe is suitable for machining the
shoe surface.
When removing surface, do not exceed the
maximum diameter cast in the brake drum.
47. Be sure to remove any metallic chips and
contamination resulting from drum machining.
Re-Mount Hub and Drum
Refer to Figure 152
48. Re-pack any bearings removed.
49. If replacing inner bearing seal , orient it with the
seam side out (away from bearing). Seat the seal so
that it is completely inside the narrow diameter of the
hub, and close to, but not touching the bearing
cup
.
Machine Damage Risk:
Seals are hollow metal structures and are somewhat fragile.
The are not intended to be in contact with the bearings. When
installing them, carefully align them so they are concentric
with the shaft hole. Apply insertion force across the entire face,
or at least equally along the entire outside diameter (as close
to the seal O.D. as possible).
50. Carefully place drum/hub assembly on spindle.
51. Insert re-packed outer bearing .
52. Add spindle washer and castle nut .
53. Tighten nut until drum/hub does not turn freely.
Loosen nut 1/6 turn, and as much looser as needed
to align hole in spindle (not shown) with notches in
nut.
54. Secure nut with cotter pin . Install dust cap .
Heavily scored, worn or oversized drums can reduce brake
performance or cause loss of braking. This could result in
death, serious personal injury, or property damage.
Failure to remove chips can cause bearing failure, brake
failure or wheel/spindle separation. This could result in death,
serious personal injury, or property damage.
Figure 151
Brake Drum
29635
Wear a respirator equipped with a HEPA filter approved by
NIOSH or MSHA when grinding or machining brake drums. In
addition, do such work in an area with a local exhaust
ventilation system equipped with a HEPA filter.
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Figure 152
Re-mount Hub and Drum
29642
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