Removed alternator, sprayed brake cleaner inside and out.blew it out with air reinstalled it. works fine. charging at 14.5 volts .dont know how long it will last????? Do you?
I think the only thing that cleaning an alternator could fix would be a stuck "brush". A brush is a common part of an electric motor (or alternator) that wears down over time. They normally have a spring that holds tension on them as they wear. If the brushes were "stuck", the alternator would stop charging. If this is what happened, it should keep working for a long time - until the brushes stick again or fail completely.
Of course since you removed and replaced it, the problem could have just been a bad connection.