I have several MTH Railking engines: GS-4, Hudson, Challenger, Big Boy and GG-1.
All ran great on my over head loops. That was until I installed cross over switrches.
The engines would phyically stall over the switches. It took some time and a lot of picking and testing.
I found out ALL of the screws that hold the wiper pads are a tad to long. They catch the rail head of the cross over rails.
They are as tight as I dare make them.
I don't have this problem myself on switches. I don't have crossovers on my layout. You can see Ray's solutions on his website:
http://www.rayman4449.dynip.com/gardenrr_mods.htm
look under the bigboy and slider and screw problems, Joe
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