[Walt Fricke]

Ironman - over voltage occurs when the voltage regulator fails in an overvoltage mode. That is perhaps more insidious than failure in the under/no voltage mode, where your battery doesn't recharge and you catch on because the engine stops at night. Overvoltage sometimes can be detected by the smell the battery creates when it off gasses - sulfuric acid?

It appears the only fix is a new VR. And sometimes even new VRs are faulty - I had one last only a couple of months. It doesn't appear that overvoltage problems can arise from the alternator itself. However, under voltage can occur due to failure of one of the several diodes, both high and low curent, in the alternator.

Voltmeter, voltmeter, voltmeter!