Engine runs on tubular but shorts on Atlas- Solved!

Is it PS2? I'd pull the 7 pin connector off at the board and see if the short goes away.

I'd have to guess that something went back together wrong. Usual suspects are reversed rollers, wires touching, etc. You have to trace where the short is occurring.

I get that it only shorts on your Atlas. Might be something easy you've overlooked.

Smoke Stack Lightnin posted:

"The truck, roller pickup and wiring reinstall went back together with no problems. My test track (conventional power) is tubular and the engine started up fine. When I place it on my Atlas lay out there is a dead short. I would think roller clearance shouldn’t be a factor since wheel and roller alignment should be relative despite the track brand. I’ve tried the engine on various areas of the layout to no avail but it starts up fine on tubular. I’m using a Lionel 4651 transformer on the test track and a MTH Z4K on the layout. Could the Z4K be more sensitive to shorts?

Thanks...Rich"

If it did not short before your repair, I'm not sure why the Z4000 would be the cause now. 

My guess is at least look at the pickup roller and see it it can contact the truck frame. I don't have any Atlas track, is the center rail higher than the outer ones? 

First, eliminate the obvious variable:  does any other engine short on the Atlas track?

So what was the solution?

Hi Roy. I removed the spring contact bracket from the post. Cut the connectors off. Soldered 4 leads to the respective existing wires long enough to set the shell out of the way for future repairs. Soldered the 4 leads to their respective contact pad. I basically bypassed the factory contacts. Now there is a tether. All is right in Plasticville!

Rich

Smoke Stack Lightnin posted:

Hi Roy. I removed the spring contact bracket from the post. Cut the connectors off. Soldered 4 leads to the respective existing wires long enough to set the shell out of the way for future repairs. Soldered the 4 leads to their respective contact pad. I basically bypassed the factory contacts. Now there is a tether. All is right in Plasticville!

Rich

That fixed a short which occurred only on Atlas track? The MTH body to frame connector?