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Q & A: MGA Charging Problem

So as to not waste your time, I'll get right to the point:
My MGA 1500's charging light came on yesterday. I spent some time
(probably not enough) viewing some of your online videos. In my
'diagnosis' phase, I connected the field terminal on the generator direct
to the battery for a short time, and checked to see if the charging light
was extinguished (it wasn't)

Then I monkeyed some with the regulator, including pushing on the two
contacts once or twice (this was BEFORE I read your admonishment not to do
this)

Finally I followed your guidance to jumper the Dynamo and Field terminals
together, and take a voltage reading to ground.. Nothing.. then your
second advice to momentarily touch those connections together and look for
a spark... again nothing.

So, removed the generator, and found in both brushes severely worn, one
had broken up in its holder. Aha... I carefully replaced with new brushes
I had on hand, and reassembled, using a bit of Dielectric grease on the
brush screw terminals. After assembly, I spun it by hand, and visually
checked that the brushes were seating on the commutator.

Alas, after reinstalling the generator, cleaning the contacts on the
control box, resetting the regulator contacts to .015, and polarizing
twice, I'm still getting no voltage output from the generator, using the
two methods described above.

1) Do you think I may have damaged the windings in my ham-handed
checkout?

2) I'm not averse to just springing for a new generator, but first
wondering if you have any other possible actions I could take to revive
it? (At just a bit over $100, it just doesn't seem worth it to try my
luck again with one of the auto electric rebuild shops around here)

3) If a new generator seems to be the advice, will I encounter any
difficulties removing the pulley from the old?

4) Although my car is in superb physical condition, I am finding that
basic preventative maintenance tasks seem to have been deferred by the
P.O. Based on my generator brush discovery, should I just go ahead and
yank the starter and check those brushes, or assume that the intermittent
starter usage might result in longer lived brushes?

There are four components in the charging system: generator,
control box (regulator), wiring, and battery. Polarize your rebuilt
generator and test it on the car by jumping between the D and F. You should
get a big flash ... read more