Great Plains NTA2007HD Operator Manual - Manual (Page 131)

Great Plains Manufacturing, Inc. Contents Index Maintenance and Lubrication 127
04/04/2011 Contents Index 166-283M
Brake Drum Maintenance
Refer to Figure 122
46. Inspect the shoe surface (the inside rim). Normal
appearance is dull gray, with no more than light scor-
ing and light wear.
One or two light score marks are not cause for resur-
facing 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 0.51mm (0.020in) oversize, or has
0.38mm (0.015in) or greater run-out.
Brake Drum Resurfacing
47. A standard drum lathe is suitable for machining the
shoe surface.
When removing surface, do not exceed the maxi-
mum diameter cast in the brake drum.
48. Be sure to remove any metallic chips and contamina-
tion resulting from drum machining.
Re-Mount Hub and Drum
Refer to Figure 123
49. Repack any bearings removed.
50. 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
.
Null4.aac:
Equipment Damage Risk:
When installing seals, carefully align them so they are concen-
tric 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). Seals are hollow metal
structures and are somewhat fragile. The are not intended to
be in contact with the bearings.
51. Carefully place drum/hub assembly on spindle.
52. Insert re-packed outer bearing .
53. Add spindle washer and castle nut .
54. 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.
55. Secure nut with cotter pin . Install dust cap .
Null4:
Brake Failure Hazards:
Remove chips. Do not re-use heavily damaged or worn-out
drums. Failure to remove chips can cause bearing failure,
brake failure or wheel/spindle separation. Heavily scored,
worn or oversized drums can reduce brake performance or
cause loss of braking. This could result in death, serious per-
sonal injury, or property damage.
Figure 122
Brake Drum
29635
Non-Asbestos Fibers and Metal Dust Hazards:
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 ven-
tilation system equipped with a HEPA filter.
1
2
Null4:
Figure 123
Re-mount Hub and Drum
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