More issues...arrggghh.

So the forklift had been charging for months, then we started having problems again. We cleaned up all of the connections and that seemed to get things back to charging. Then a few weeks ago, not charging again. We had to charge the battery to get it started. While running, battery voltage is ~12.5V with the voltage regulator connected or not.

We replaced the voltage regulator this morning. I had my Fluke multimeter connected to the battery when I started it. Battery was at ~12.5V, forklift started, battery voltage climbed to 13.8V (yeah!), then after a few seconds it started climbing all the way to 15.5V sometimes coming down to 15V but wouldn't come back down so I turned it off. Could this be anything other than a bad voltage regulator?

The battery holds a charge when charged with a 2A charger for 12 hours, and the charger only goes up to about 13.8V so I don't think it's a bad battery.