[bearone2]

Originally Posted by wild man

When I stated that the battery showed 12.5V with the engine off, I actually meant that in a "good" way. It probably would read a quarter volt or so higher if it is given a full charge and then left to stabilize for 2 hours. It is a NAPA professional line (The Legend) 75 month battery with CA rating of 815, and a CCA rating of 660. Although at first glance, it does appear to be the "unmaintainable" variety, it really is not. The caps are removed as 1 rectangular piece of plastic covering half the battery. And I do maintain it well, keeping it (and the terminals) clean, and always making sure the electrolyte levels are up to the split rings. Specific gravity testing comes up good on all cells.

I agree that "a high rate discharge test is the best" way to test a battery. And there is no more convenient of a way of conducting such a test, as cranking over the engine. It is not too often that VR's start to fall short on their regulating capabilities, so most likely some turns in the alternator coils are starting to short out. But I still see where there is a slight possibility that it could be the VR. That is because the brushes that feed the VR juice to the alternator's field winding are attached to the the VR, itself. And if they are worn down to the point where they are starting to loose connection with the alternator's commutator rings, I think that could possibly be making it show that symptom's that I am seeing. In summary, the question I was asking in this thread was, what are the chances that is the problem, and not the alternator itself?

no, starting isn't a hi-rate discharge test.

connect the tester to both terminals, hold the switch for 10 secs and see if the batt drops below 9.6.

see post #4.