[ndutton]

Kelly et al,

Please keep in mind that all this resistor business is as yet untested, purely what we're thinking at this point. I picked up my resistor yesterday and will get it installed and tested for hopefully reduced coil temps as soon as I can. There are a few other listmates at a similar level of progress.

We think we're on to something based on theoretical analysis but until real world testing is complete we don't know for sure.

Something recently dawned on me though. Have you noticed that with the recent rash of overheating coil reports not a single one was a Moyer coil? Why would that be? What's different about his coils?

I'm pretty sure it's the internal resistance. The auto parts boutique coils - and the Flamethrowers - are 3 ohm coils and Moyer's are 4 ohm. That 1 ohm difference doesn't seem like much until you look at it in terms of percentage. Moyer coils have 33% more resistance than the others.

Well, enough talk-talk. It's time to get the testing done.

Triton,
The coil - post is not a ground. Disconnected it has continuity to the coil + post reduced by the internal coil resistance. A switching ground is provided to the - post by the ignition regardless of whether it's points or EI. Readings taken at the - post will be confusing as it's switching on and off. Actually, to confuse matters more, what you're reading at the - post mimics alternating current. The significant reading you need is from the coil + post to the engine block with the engine running. That reading should be equal to the alternator output minus the ignition wiring voltage drop. On my boat the voltage drop is 1 volt.

Further, your alternator output voltage indicates it and your regulator need to be repaired or replaced, period. 17 volts is not right and will damage components as you have already seen. In my estimation, based on your description and my affection for single wire internally regulated beefy alternators, I'd replace the alt with a new one (I love my Delco), replace the coil with a new 4 ohm and replace the EI because it too has been stressed. All this will cost a couple o' hun but you'll be done with it and back out on the water.