Right slick mag problem

[albertaflyer]

Hi,

Just got back from a flight and before shutdown I check the mags. Anyways, when I switched to the right mag the engine was going to quit. It did this to me about 2 months ago. At that time I pulled the mag and had it checked. Everything was good. Checked the wiring and the ACS mag switch and it was fine. Put it back together and it was fine until... Fast forward to today. Pulled the ACS switch out and cleaned the contacts, but to no avail. Any ideas? When I did my run up before the flight, the left mag dropped about 50 and the right about 75 rpm. Im guessing it has to be the switch because if it was the mag wouldn't it run a little rougher even when switched to both because your only actually running on one mag. Or could it be a grounding issue? It didn't even run rough it was killing the engine when switched to the right mag.
Thanks for any ideas

[DanBaier]

You might want to see if you haven't inadvertently grounded the mag with the p-lead (some stray part of the p-lead is grounding to the case). It's a little tricky to find, but I've had this happen.

(You shouldn't try starting with the p-lead disconnected, the engine might kick back and cause some damage. You want the right mag off line when you try to start.)

Dan

[scottmillhouse]

I had a similar problem with a right slick mag that turned out to be the coil. It worked fine when cool but once shut down for a short while it would heat soak and short out and then be fine once again when cooled. It was a challenge since it would cool down by the time the tools were out and the cowl was off. With high coil and rebuilt cost- a call to Aircraft Spruce and then back flying in a day with a new mag.

[albertaflyer]

Thats interesting! So through expansion it would make contact then Im guessing.

[bhester]

Tempest makes a replacement coil
http://www.aircraftspruce.com/catalo...clickkey=40283