and their contact screws for dirt or corrosion, and clean as
necessary. Retest alternator. If problem still exists, disas-
semble the alternator for further tests and inspections.
(4) The alternator may also be checked for
The test light should be a two filament sealed beam unit
connected so the filaments are in parallel. Such a light will
act as a load as well as an indicator. The test light should
illuminate with equal brilliance on each phase (Test A, B,
and C). If the light is noticeably dimmer on one or two
phases, a defective diode trio, stator, or power diode is
1000 rpm, note the voltmeter reading. If the voltmeter
rises as contact is made between the short piece of wire
and the outer brush terminal, the alternator is good.
Remove the diode trio and test. If the diode trio tests okay,
the voltage regulator should be replaced.
(3) If the voltage fails to rise during the full field
test, remove the voltage regulator and carefully inspect it
for a printed circuit path that is burned open. This will
generally be the track from the positive regulator terminal
to one brush terminal. If this condition is found, replace
the voltage regulator. Also check the brush spring caps