Komatsu 830E Shop Manual page 134

3. Failure to operate with high current draw indi-
cates:
a. A direct ground in the terminal or fields.
b. "Frozen" bearings (this should have been
determined by turning the armature by
hand).
4. Failure to operate with no current draw indi-
cates:
a. Open field circuit. This can be checked after
disassembly by inspecting internal connec-
tions and tracing circuit with a test lamp.
b. Open armature coils. Inspect the commuta-
tor for badly burned bars after disassembly.
c. Broken brush springs, worn brushes, high
insulation between the commutator bars or
other causes which would prevent good con-
tact between the brushes and commutator.
5. Low no-load speed and low current draw indi-
cates:
a. High internal resistance due to poor connec-
tions, defective leads, dirty commutator and
causes listed under Number 4.
6. High free speed and high current draw indicates
shorted fields. If shorted fields are suspected,
replace the field coil assembly and check for
improved performance.
Disassembly
The cranking motor should be disassembled only as
far as necessary to repair or replace defective parts.
1. Note the relative position of the solenoid (53,
Figure 2-8), lever housing (78), nose housing
(69), and C.E. frame (1) so the motor can be
reassembled in the same manner.
2. Disconnect field coil connector (42) from sole-
noid motor terminal, and lead from solenoid
ground terminal.
3. Remove the brush inspection plug (52), and
brush lead screws (15).
4. Remove the attaching bolts (34) and separate
the commutator end frame (1) from the field
frame (35).
5. Separate the nose housing (69) and field frame
(35) from lever housing (78) by removing
attaching bolts (70).
6. Remove armature (45) and drive assembly (71)
from lever housing (78).
7. Separate solenoid (53) from lever housing by
pulling apart.
D2-16
FIGURE 2-8. CRANKING MOTOR ASSEMBLY
1. C.E. Frame
2. Washers
3. O-Rings
4. Insulator
5. Support Plate
6. Brush Plate Insulator
7. Washers
8. Plate & Stud
9. Plate
10. Brush Holder
11. Lockwasher
12. Screw
13. Brush (12 required)
14. Lockwasher
15. Screw
16. Brush Spring
17. Screw
18. Screw
19. Screw
20. Lockwashers
21. {;ate
22. Brush Holder
Insulator
23. Screw
24. Lockwasher
25. Washer
26. O-Ring
27. Bushing
28. Insulator
29. Washer
30. Lockwasher
31. Nut
32. Nut
33. Lockwasher
34. Screw
35. Field Frame
36. Stud Terminal
37. Bushing
38. Gasket
39. Washers
40. Washers
41. Nut
42. Connector
43. Lockwasher
44. Nut
45. Armature
46. Field Coil
47. Shoe
48. Insulator
49. Screw
50. Washer
24 VDC Electric Supply System
51. O-ring
52. Inspection Plug
53. Solenoid Housing
54. Lockwasher
55. Screw
56. Plunger
57. Washer
58. Boot
59. Washer
60. Spring
61. Retainer
62. Snap Ring
63. Shift Lever
64. Nut
65. O-Ring
66. O-Ring
67. Snap Ring
68. Lever Shaft
69. Drive Housing
70. Screw
71. Drive Assembly
72. Gasket
73. Plug
74. Gasket
75. Brake Washer
76. Screw
77. Lockwasher
78. Lever Housing
79. Washer
80. O-Ring
D02023