TM 10-4320-315-24
3-19. MAINTENANCE OF ALTERNATOR - (Cont)
(11)
Remove screws (26) with captive washers that secure diode assembly (27) to stator assembly (13).
NOTE
•Diode plate has three isolator terminals that may stay with diode plate or rear of stator housing.
•Isolators are three different shapes that assist in correct reassembly.
(12)
Remove seal (28) from diode assembly (27).
(13)
Unsolder three wire leads of stator assembly (13) from diode assembly (27).
b. INSPECT.
(1)
Inspect brushes of voltage regulator for wear. Replace if worn or pitted.
(2)
Check bearings on rotor assembly for smooth operation. Replace if rough operation.
c. REPAIR.
(1)
If necessary, remove by pressing off collar (16) and bearing (17) from shaft of rotor assembly (12).
(2)
If necessary, remove by pressing off bearing (18) from other end of shaft of rotor assembly (12).
(3)
Install bearing (18) on shaft of rotor assembly (12).
(4)
Install bearing (17) and collar (16) on other end of shaft of rotor assembly (12).
d. TEST.
(1)
Test diodes as follows (Figure 3-18):
(a)
Use multimeter to check resistance on each diode by placing one lead touching rear wire behind diode
and the other lead touching casing of diode assembly. Record reading.
(b)
Reverse leads and record second reading.
(c)
Compare readings. If readings are not low in one direction and high in the other direction on each
diode, replace entire diode assembly.
(2)
Test stator as follows:
(a)
Tag three disconnected stator leads A, B, and C respectively.
(b)
Using multimeter, test for continuity between A and B, A and C, and B and C. If there is no continuity,
an open winding is indicated and stator must be replaced.
(c)
Using multimeter, test for continuity between A, B, or C and stator lamination. If there is continuity, a
grounded winding is indicated and stator must be replaced.
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