072 Super Snap LH 6-21399

Is it just this one loco that's shorting, or do you have the same issue with other locos?

This is a known issue with the right-hand O72 switches; I've never heard of or experienced this with the lefties.  If you have a meter, check for continuity between the frog and the rails just before the frog, which I think are called the closure rails (both straight and curved--my screwdriver is pointing to the "problem" rail in the photo). If you have continuity, that is your problem. There needs to be a gap between these rails and the frog, otherwise you'll get a short and sparks with everything that has a pickup roller.

One fix is to remove the rails, grind them down so there is a gap between them and the frog, and reinstall them. Another fix that's easier and I've found to be just as effective is a strip of electrical tape on the closure rails.

Hope this helps; keep us posted on your results.

John

Thank you BlueComet400

I’ll get on it tonight or tomorrow.

John,

You were correct it is a RH switch.  Would you take a Dremel and use a cutting wheel to widen the gap?

I also have a Lionel 5165 072 switch that only works with fixed voltage. Any suggestions?

Thank you,

Richard

A Dremel cutting wheel would do it, but the challenge is getting deep enough to cut the entire rail. On my switches, it was the base of the rail that was touching the frog. I recommend trying the electrical tape first. That has worked flawlessly for me. Just make sure the rail is good and clean or the tape won't stick.

As for your other switch, take a look inside the hole where the fixed voltage plug goes. There should be a tab that touches the pin in the center of the hole. If the tab is missing or isn't touching the pin, that is likely the problem as the tab/pin connection is what sends track power to the switch motor. When inserted, the fixed voltage plug separates the the tab from the post, which disconnects the track power from the switch motor.