N51DV is finally flying again. The annual is complete. But I can't say 
everything is in order. Thanks again for the help. Here is some feedback for 
the benefit of others.

New ignition harness for the Eisemann mags:

I took the advice aimed at eliminating the radio noise problem. I found several 
places where RF could be coming from the ignition system. I had new p-leads 
made (they are not available as a part). I replaced the filters (not cheap at 
more than $60 each). I replace the ignition leads and had the magnetos rebuilt. 
The ignition leads come in a kit that does not include the nut plates that 
connect to the magneto. Be very careful to mark the old wires to ensure that 
you get the right length wire on to the right (correct) nut plate on the 
correct position. Once you have cut and stripped the wire for the connection 
inside the mag, you have severely limited you choices of where to connect that 
wire to the nut plate.

One mag feeds the upper spark plugs and the other goes to the lower plugs. A 
big lesson that I learned was to follow the manual drawing instead of the 
markings on the nut plate. If you route the wires to the cylinders as marked on 
the nut plate, cylinders 2 and 3 will not fire properly. I was able to start 
it, but it was definitely not happy. After switching 2 and 3, everything worked 
great.

Radio ghosts:

So the primary reason that I have been grounded for the last four months is the 
radio problems. After rebuilding my ignition system, I was hopeful that 
everything would be fixed. On the taxi back to my tie-down, I check my radio 
and the interference was still there. After a discussion with my A&P, I tied 
her down and did fired her up to do some more diagnostics. As you might expect, 
the radio was clean. I let it warm up for 15 minutes. Still no problems.

The following weekend, I went to do some touch and go's. The radio seems clear 
but very weak. I had the radio and my headset turned up full. I copied ATIS and 
went to set my altimeter. As I touched the knob to change the settings, the 
volume of the radio jumped. What have we here? I reached out and pushed on the 
panel, and the volume changed. Every time that I flexed the panel I got a 
different volume. As the engine sat idling, the radio warbled up and down 
making it impossible to hear. I switched to my handheld radio, and everything 
was fine in that world. My guess is that I have some sort of grounding problem. 
Does anyone have any thoughts?

Thanks.

Frank Nelson
N51DV – 415C
TOA


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