alternator/volt gauge/a short....whats the score here

["TalksToGod" <5n-@xxxx>]

I am having a tough time with my DeLorean's electrical system. The
case is- my regular Motorolla alternator is producing only 10.5 volts
shown on the gauge constant. Constant meaning-When I am to put on my
headlighs or my fan (heat/AC) the voltage will drop down. The problem
is-with my headlights on and the gauge running well below 10.5-I
cannot accelerate there simply is not enough power to run my
headlights and run the engine at the same time hence there is a power
drop in my motor which comes immediatly back once the lights or
whatever is on is shut off. My thoughts were a bad
alternator/battery/contacts/etc. Now I have come across something that
stumps the hell out of me-whenever it rains and i drive the car, the
gauge will show a constant reading inbetween the middle 13, and the
orange lower mark-it is about 12 or 11.5 volts. At this reading with
my lights on and even my fan on, my engine still has enough power to
run good at higher RPMs. With this, I figure the water is creating a
ground-so I must have a short somewhere. If anynone can suggest a
place to look a place to start-or maybe you have had a similar
situation which you fixed-I would appreciate to hear what you have to
say. To clear up more on what I already tested-I ran the engine and
unplugged all the fuses that wouldn't stop the engine from
running-still 10.5, also cleaned up alternator contacts aswell as
starter contacts. I was considering the purchase of a 150 AMP
alternator from Specialty, but if I can fix my current problem, I
could really use the save of almost 300 dollars. Alternator has new
brushes etc. thanks again for the help guys--Dani