O gauge Locomotive is sporadic

[Ktstevenson60]

I took my 1963 Santa Fe to a RR shop thinking it needed a repair and it ran perfectly. For some reason on my track is sporadic. I’ve cleaning it over and over with electrical part cleaner. Track looks and feels clean but it’s old. What’s weird is when I hold the front end down on the track and keep back end off, to loco runs great.

help!!

thanks,
Ken

 

[bnsf971]

Try cleaning the track connectors. They are the little pins on the ends that go into the following piece of track.

 

[Iron Horseman]

when I hold the front end down on the track and keep back end off, to loco runs great.

Hmmm, loose wire on one of the trucks? Such that when tilted it makes contact but when you put it down it "lifts" away. I'm guessing. Can you try the same thing with the shell off and maybe see a wire move?