6-3. ALTERNATOR REPAIR/TEST (CONT)
Clean brushes (47) using soft, dry cloth.
Clean slip rings on rotor assembly (9).
Place rotor assembly (9) in a lathe, with
slip ring of shaft free.
While rotor is spinning in lathe, hold No.
00 sandpaper or 400 grit silicon carbide
paper against slip ring (50) surface.
After polishing slip rings (50), clean
using low pressure (15 psi maximum)
Inspect roller bearings (13 and 45) for rough
rotation or visible damage. Replace if faulty.
Inspect brushes (47) for excessive wear. Replace as needed.
Inspect brush springs (48) for distortion or discoloration. Replace as needed.
Test diode trio (27).
Connect multimeter between diode trio
single connector (51) and each of the
other connectors (52,53, and 54) in turn.
Observe resistance reading.
Reverse multimeter leads, or reverse
meter polarity, and repeat STEP a, above.
At one polarity, resistance reading should
be low and at the other polarity, resistance
reading should be very high, if diodes are
good. If both readings on same set of
connectors are either high or low, the
associated diode is faulty and entire diode trio must be replaced.