Misfires Module B

Thanks Bill, and yes you are right about a totally unnecessary $1000 part.

Enough for today.  I hope to go after it again tomorrow.  Old age is catching up with me and being retired, afternoon work no longer fits my lifestyle.......Tom

Well, it's with my hat in my hand and egg on my face that I write this.  I wanted everything back to original before moving on to examine the high voltage coils.  Somehow I got the connectors mixed up and had a devil of a time getting that straightened out, but I finally got it right.   Of course I test ran it to verify.  Someone posted a daunting Rotax ignition problem quite awhile back.  After many hours of troubleshooting, the end results were that he had replaced a bad spark plug with a new defective one, and it took them down the garden path.  Well, I guess I did the same thing.  I had another brand new full set that I was saving to install when I had it running properly, but I decided that it would be well worth $25 to just do it, even though I had already replaced all of the B side spark plugs once.  Well it ran like a top, and I actually was able to fly it today.  It was a lot of work and I learned a hard lesson, but  I did become quite familiar with the Rotax ignition system.

Bill, my sincere apologies for my stupidity, even though some fault should be shared with my NGK supplier.  It was a pleasure working with you and comforting to have your guidance.  So Sorry for this, buy I sure am a happy camper...Tom 

I am Happy you have solved the problem.  

This thread will be beneficial for the next owner trying to troubleshoot his ignition system.

I spent a lifetime troubleshooting electronics.

What I learned is that 99% of the time it is something simple.

It just takes a little Time, Effort And Thought to find the problem.

"Shotgun" Troubleshooting is expensive and seldom finds the problem.

That is why I cringe every time someone wants to "Throw Money at the Problem" and just start replacing parts blindly.

I do not even consider a problem truly resolved until it can be recreated.

You may very well have a bad plug; I am not doubting that,  but until you reinstall the "Bad Plug" in an "A" Lane position and the problem returns, it could just as well have been a marginal connection of a Spark Plug Connector that was resolved incidentally when the Plug was changed.

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Whenever I eventually find an object that I lost,   After I find it, I sometimes keep searching.

I tell people that I am still searching because "I didn't want it to be in the last place that I looked."  

So I keep on searching after I find it because "You never know what else you may Find!"

Bill, I put all of the old plugs in my labled spark plug stand.  So, it will be easy to reinstall them in their original location, and I should be able to verify that the condition returns.  I will do that soon.  I would just like to fly for a few days first.  I'll let you know the results....Tom

Okay, popped off the cowl, swapped the old plugs back in, and experienced the same rough running on ignition B.  Has to be a bad spark plug.  Put the new ones back in and I all good again.  So, I pitched all 8 plugs, even though I am quite sure that it is probably just one that is bad.  I'm just done with the whole set, and I am taking no chances that I might be back there some day.  In fact, I had another set of old plugs and I pitched them as well. For $25/set, I'll just swap them in a set.  I have not been very successful in identifying a bad spark plug anyway.  Thanks for all your help............Tom