I have an MTH Premier Grand Trunk Western GP9 diesel-electric locomotive model that was stalling at slow speeds over the switches on my Atlas O tracks.
After watching where it stalls on the switches, I guessed that the front truck had a wire disconnected.
In fact the aluminum wire had been cut too short and never inserted in the wire nut.
I cut a section of copper wire to put one end in the wire nut and twist the other end to the too short wire.
I could not find any tiny wire nuts immediately, so I used hot glue to insulate the wires.
Now the GTW GP9 diesel loco is running over the switches at the slowest speeds possible.
Andrew
Falcon Service