This is an odd one. I had a section of track (3 or 4 track pieces) that were dead. Upon replacing one piece at one end of the section the entire section came live. Also, I had a section of 3 or 4 track pieces that were dead with a bumper piece on the end. When I removed the bumper the section of track went live. I can't understand how that would work. Any ideas out there?

They are M tracks. It's an old set from the 1950s.

Thank you. I’ll give it a go.

Hi Chuck
I have used this M track for decades and I love it.
Two things that may help you a lot:
- prepare long nose plier with a piece of metal (screw or nut) so that it limits the closing. Use it to straighten the fishplates (rail joiners) so that the "grip" come back as with new M track rails. The closing limit on the pliers is there to prevent you of squeezing too much the joiners.
- inspect the central tongues of each rail and bend them very very little upwards. This make the stud contact so much better.

Nothing is more aggravating (I think) when you have intermittent contacts between track section.

Cheers
Jean