[bobcowan]

I am certainly not an electrical engineer. So I look for simple tests and simple solutions.

As I understand it, an ammeter measured current draw vs. available current. Very differant than a voltmeter. I would be curious to see what the volt are in each of those situations.

In any case, it sounds like there's too much draw, and not enough avalailable amps. you keep adding a load, until the system is maxed out. The engine dies because there isn't enough juice to run the ignition, and it it quits.

The battery should supply enough juice to make up the differance. For a while. You can run the engine on battery power alone. But if the battery doesn't have enough reserve, you're dead in the water.

After checking all your connections, I would have both alternater and battery load tested.