On Tuesday, May 21, 2013 12:23:28 PM UTC-4, Stormin Mormon wrote:
I used to have a HF float charger. Left it clipped on to a marine battery.. A couple months later, the battery was down on water. Too 1 1/2 quarts to fill it up. The battery did not survive. If you use such a junky charger, please put it on a 24 hour lamp timer, and run it an hour a day.

The harbor freight charger is incapable of producing enough current to boil off a battery. That charger would burn up producing enough current to boil off a battery.

You had some other problem, probably a shorted cell.