In my last post I claimed that the problem was solved when I put in the new ignition. Turns out it was only solved for the short yard test runup. When I got to the field the problem magically reappeared. At that point I thought it was time to put a for sale sign on it. Well I called Terry at C.H. Iginitions and apologized for being an idiot, and that he was right in thinking that it wasn't an ignition problem. He gave me some more suggestions, some of which I had tried and some of which I *thought* I had tried.

That evening I reluctantly pulled the cowl off and strapped it down in the yard again. The first and easiest thing I could think of to try first was to grab a different battery and plug directly into the ignition bypassing the switch. I started the plane and it ran perfectly. Now I'm starting to feel stupid, yet a large grin began to grow. So now I've narrowed it down to either a battery or the ignition switch. So I plugged the original battery directly into the ignition and it again ran perfectly. You got it, a bad switch! It was a brand new JR switch that lasted exact 1/2 of a flight and then decided to give me a month of headaches. I certainly must have been imagining that we bypassed the switch in our initial trouble-shooting because I flew it 4 times today and it ran like a dream.

The odd part was it ran very well at idle, all the way up to about 1/2 throttle. Once I got above half throttle it would start a very steady and nasty surging. I guess when the engine vibration got to a certain frequency it caused the switch to have an open condition until the engine dropped back down below a certain RPM in which case it would close and run up again. At any rate. I *strongly* suggest you seriously check the switch if you have a similiar problem. Check it twice just to make sure you really checked it the first time!

I want to thank Terry for bearing with me and I promised him that I would post my ignorance for the rest of the world to see, and hopefully benefit from.

Signed,
Embarassed but happy Never2Windy