After changing both batt and the alternator we boiled over the passenger side batt. After looking to this forum for help we found a bad connection between the the two and got it cleaned up. After that everything seemed fine for a day with the alternator putting about 14.5 volt to both batt. Now its charging about 12.10 to both and about 12.75 with the lights and radio on. Is this normal or do I have another problem?

 

I wonder if the damaged battery is drawing down the alternator.

 

Well did you replace both of those batteries?

If you boiled the fluid out of one you likely damaged either one or both of them.

Get new batteries in there, if you are still only charging to 12.10/12.75V with the engine running then the alternator is the problem and you should pull it and have it checked by Sears or Autozone or w/e shop/store you want to bring it to.

If those are the battery voltages with the engine OFF (NOT RUNNING) then you are well within the acceptable range.