Ignition coil issue - 1974 Evinrude 9.9

I am new to this forum and self-taught/new with outboard repairs. Last year I replaced both ignition coils on my Evinrude when I found that one cylinder wasn't firing (spark plugs were new and one was consistently not getting spark). After I replaced the coils (with BRP coils), both cylinders were firing and the motor worked great for about 2 months. Then the same cylinder seemed to quit (while running, I got shocked after touching the boot of the non-firing spark plug). I took the multi-meter to the motor this spring and found that the spark-plug leads were good, but both coils had output resistance that was below what I found posted for spec (supposed to be 200-400ohms but found one to be 12 ohms and the other, bad coil, to be 6 ohms). The resistance on the primaries for the coils seemed to be good (1.1 ohms each). I couldn't figure out how to test the trigger or stator on my model of Evinrude, but I found that when I switched the connections from the magneto to the coils, the same coil was consistently bad, which I believe means that the problem is isolated to the coil. And I should specify, the low coil resistances were measured when the coils were off the motor.

My questions are:
1) why would my new coil resistances be below spec?
2) why is one coil half the resistance of the other?
3) what would cause a new coil to die within a few months?

I ended up getting one of my coils replaced on warranty (due to its failure). After getting both coils back on, I was seeing good spark when I spun the flywheel with the plugs out. However, when I started the motor up I found I was getting shocked when I touched the spark plug boots. This was also happening when the coil went bad last year. The spark plug leads and boots are both new, so I'm not sure where the issue might be. The coils are grounded and the ignition system appears to be properly grounded as well. I have included pictures in case anyone can see something that I am missing. I am also looking for guidance on checking the trigger and stator using a multi-meter. Non of the instructional videos I have found for 9.9's seem to have the type of wiring that mine has. I am also unable to remove the flywheel without sending the motor to a shop, which I am trying to avoid unless I can't figure this out.

Pappy said:

Don't touch the spark plug boots when running!! Actually you should be able to but not knowing how your mechanic did the ends of the wires or whether or not he used the proper thick OMC boots....who knows.
What you failed to mention in your latest post is whether or not the engine now runs properly with the new coil ???

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I did get it running and it seemed to be running ok. Had a tougher time starting compared to last year, but It's never been that easy to start.

My main concern is that I might burn out another coil from some kind of grounding issue, could that happen? It was surprising to have had a new coil burn out in less than a year and I would love to avoid that happening again, especially since coil prices have gone up!

Electricity is lazy. It will always find the path of least resistance to ground. If you had no ground you would have no spark. The secondary coil windings find their ground by passing through the spark plug electrode, arcing or sparking and grounding on the tang where you set plug gap. Your coil primary is grounded to the mount boss.
Reset your mixture and lean it to the point of a cough or sneeze then richen just a little. Engines that are too rich or too lean will take a bit longer to start. Properly tuned your engine should produce very little smoke at idle and be very smooth running with little powerhead shake.

Oh great. I have a 76 9.9 I've not went through yet. It starts up and that's all I know. With a busted thrust mount on top, I'm thinking it's not a keeper.

It's simple to make/use a puller, check all wiring, possible new wires defective?
They are great little motors.

Thanks Pappy, that's what I've been thinking as well. Although there are a couple work-arounds on a well-known forum: OMC 9.9 - 15hp

I've been looking for a donor motor for a year now with no luck. People around here seem to think just about anything with a prop is made of gold. Not sure how much time want to put into this little motor. I have bigger fish to fry so to speak. ;-)