You need to do a better checkout of the alternator function. It's possible for an alternator with a bad rectifier diode to have enough voltage to charge the battery, but at a very low current output. For instance, a 65 amp alternator with one bad diode will charge at about 10-12 amps. Have someone check out the maximum amperage output as well as the voltage.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!