Trying to isolate whats burning ignitor/coil

Hello all,

First, I would like to say thank you for such an amazing forum! This will be my first post as I have been able to search and find all other inquires/answers without the need to ask. I have officially signed up with story/photos of my pride and joy but am currently waiting on correctcraftfan to review and accept my write-up.

I have an 1981 with a Ford 351 Commander.

I'm fully aware of the points vs. pertronix debate but, I'm willing to give them one more shot due to fact I'm being sent a replacement pertronix II combo (item# 91582).

I believe the error is most likely on my side vs. placing blame on pertronix. I have burnt through two pertronix I coils/ignitor, both sparked up and ran great for about 3 hours run time before leaving me stranded. A few things I have learned or feel are important...

The rpm gauge is shot and does not work, with the new replacement I plan on leaving the rpm sending wire disconnected.

I feel there maybe an issue with the wiring...(+) from ignitor goes to (+) on coil to a 4 way splice that combines a (+) wire to the carb choke, a wire runs to the (S) on the voltage regulator, and a wire that runs to the ignition.

We use accessories without the boat running such as the stereo, I believe the ignitor/coil are burning up due to this. What can I hook the (+) from the coil to that will only turn on when the motor is actually started and cut off when the motor stops.

Any help would be greatly appreciated.

Thanks,
Ryan

Thanks Gary for the quick reply,

I will re-wire the the (+) from my 6 gang accessory box directly to the fuse box vs. the current ignition switch position tonight. I should be receiving the new coil/ignitor tomorrow and will post voltage at the coil once she's started along with primary resistance.

Thanks again!

Or wire the stereo to your nav light switch

You can always go directly to the battery as well.

With a .6 ohm primary resistance in the coil, you may need a ballast resistor, Check with pertronix. Run the boat then feel the coil, it should be warm but not hot.

You have the same danger of burning up the coil with the points system if you leave the key on and the points happen to be closed. I think the ignitor II has some protection built into it.

Phew...I got back to the dock...

So, took the boat out for a spin, ran great for about an hour, then stalled. After turning everything off and letting everything cool, including my self, luckily she started back up. Coil was hot to touch way beyond warm.

Gary, just went out to check, with it running it's at 14+   with key in the on position it was at 12.4

I went to restart it to double check, no spark...hopefully protection mode is doing its job.

Calling pertronix now.

I think you will need a ballst resistor you want to limit the current(heat) in that ignition circuit to 8 to 10 amps. You are 22-24 amps. Get a resistor in that circuit. You need another .75 to 1.00 additional ohms of resistance.

Hollywood,

I do not see any mention of resistance..only a resistor which is to remove it if there is one, I do not have one.

Going to purchase new plug wire, plugs, and cap, just in case something is causing a spike.

Not much of an update (got rained out) but, after I got back from buying new cap, plugs, and wires, she started right up. Happy to see that the pertronix is atleast going into protection mode like it claims. Now hoping that tune-up will be the fix for the coil overheating. Seem so close yet so far away...I just want to go skiing...

Sorry to hear that Seals, it's extremely frustrating to say the least. It seems to have everyone stumped that I have talked to. I have been eyeing the DUI distributors but fear that this problem will carry over into that as well. With the money I have dumped so far I could have easily afforded one that's for sure. Seals please respond back with your results, I'm curious to see how it turns out. I hope my last few hail mary's pay-off tomorrow.

Ballast resistor is one of my hail mary's, I will throw the pertronix crap away if I can't figure out how to fix what I got first.

And all you did was change the plugs? What was the old gap and what's the new?

I've also heard, but not confirmed (tuber), that an incorrect rotor-plate gap can overheat a coil.

This seems to be the most logical instruction sheet for an EI conversion I've seen.

Spark plug gap should be .035 inch. Maybe that is the problem.

SNobsessed wrote: Spark plug gap should be .035 inch. Maybe that is the problem.

Thanks for the info, going to drop the gap now.

I would like to jump in here. I have had my boat, an 84 SN2001 for three years and other than changing oil and plugs once it has run flawlessly until just recently. It does have a Pertronix setup and the coil says it does not require external resister. My boat started skipping a touch upon idling back to the dock. An earlier post led me to believe that maybe the coil had gone bad. I swapped it w a new one and it runs exactly the same, so not the coil. While looking at the motor while it was idling, I noticed sparks jumping down one of the plugs from the boot to the base of the plug. So I figure I need wires. I will do plugs at the same time. When I ran the boat last week after changing the coil, it, the coil was extremely hot. Plan is to change plugs, wires, dizzy cap and rotor. Anything else? If system is performing well, how hot should a coil be? Too hot to touch? Warm? Burning hot? And last question, Autolite #24 plugs gapped at .035 as mentioned above, correct? Thanks for all the help, Mark