Ok i have a 1986 cavalier convertible, and the alternator charged when i first hookup a freshly charged battery, at 14 volts, but after about 2 hours, it stops charging at 14 and drops to about 12 volts, and drops. and stays that way for a week or so till the battery dies completely. i've replaced the alternator, belt is tight, replaced the wiring, anyone have any ideas?
Al