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Hi Matt.
re: "...When I test for a current draw reads 0.01 on the 10A setting and on the 200mA setting reads between 8.4-11.2. Which, if I'm doing this right is more or less 100 mA. Right?..."
No, not right. Watch your decimal places. Digital VOMs will not make errors of decimal place, no matter what scale -- it's resolution that larger scales don't handle well. A scale's name, such as 10 A, is really just the maximum amperage that the meter's circuit can handle; a 200mA scale can only handle up to that many milliamps, but it will also better resolve the mA at lower currents.
So 0.01 on the 10A scale is still 0.01 amps, which is really 10 mA (whereas 100 mA would be 0.10 amps) -- recall that 1,000 mA is 1.0 Amp. So on the 10 A scale, you have approximately 10 mA, but not good resolution -- it could be anywhere from 9 to 11 mA, and even those are just approximate.
But on the 200mA scale, you get better resolution, and the 8.4 to 11.2 mA that you saw is about right -- and Congratulations! You have at least eliminated the possibility of a serious battery drain through some car's circuit.
re: "...I was on the cell with my father and law while I was out there and he seemed to think it was the alternator not charging and to perhaps look at the regulator...."
If the battery charges up to 14.3 pretty quickly, the alternator seems to be doing its job. Turn on the headlights, and the interior fan (heater), and see if you've still got good voltage. If so, then the alternator is fine.
And if the voltage, after five or ten minutes (very approximate) on the battery drops to around mid-13 volts or a little more and stays there, then the voltage regulator is also working properly -- the main purpose of the voltage regulator is to avoid overcharging the battery (causing electrolyte to boil away and prevent damaging the battery).
If they work as I've described, then that's all you can expect of those components. The problem is elsewhere.
re: "...I had the battery tested at a shop this morning and they said it was OK. Would a "surface charge" give them a false reading?..."
Yes, it will give a false reading if all they did was check the voltage. That's no better than what you did with your own voltmeter -- and not worth paying them to do that.
But a good shop should also have a device to test the battery under a simulated load -- usually it's a hot wire coil (in a protective cage) that will glow bright red when attached to the battery (it simulates the load of the starter motor). Did you see them test it with that?
And last but certainly not least, a good shop should also have a battery hydrometer -- this is the thing that checks the specific gravity in each of the six cells of the battery -- and is the ultimate test of the condition and health of a battery (much more reliable than measuring voltage). You should see them suck a sample from each cell into the device to see how high a float floats. Did you see them do this?
re: ".. I'll go disconnect the battery now and get back to you with the voltage tomorrow...."
Good. I'll look for your post tomorrow.
Good luck.
Ken
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