Lionel C&O Mikado Shorting Out

There is a small detail on the bottom of the cab that is held on by a screw.  It may hang low enough to short out on the switch especially coming off a curve.

I agree with David, before going to all that work, look carefully at the locomotive.  This screams simple mechanical issue, and may save you a lot of time and trouble.

Also take a look at the pickup roller alignment. If they're not straight, I've seen some of them make contact with both rails as they pass through a switch and short it out.

That makes sense, I had the Lionel 2-8-0 Consolidation that would short out making O-36 turns, even though it was supposed to be O-31 compatible.  The roller would contact the outer rails in the turn.

I will get a magnifying glass out and take a look tonight at it.  At first glance I could not see anything that look out of the ordinary

Yes I hope it is something simple as I have less than 5 hours on this engine and it would be a shame to send it back to Lionel.

John