for the electricians to solve

[tcripe]

 I have a Williams SD-45 that I equipped with TMCC via Electric Railroad's Cruise Commander. When run forward, it stops at just about every Fastrack switch, or stops dead if run slower. But if I run the thing in reverse, there's no stopping. I taped off each roller to see if one wasn't delivering, and also checked them with a voltmeter. All good. I've cleaned the track and the wheels. When it stops dead, I can get it to light again by turning the trucks slightly. Can anyone solve this frustrating mystery?

Terry

[ADCX Rob]

 It sounds like you are losing your ground.

On Williams diesels, solder a ground wire to each of the motor cases and tie them together, using these points for your ground connection to the electronics & motors. Make sure the motor screws are snug(from the bottom).

Using the frame for ground can be very frustrating as it doesn't always result in a solid mechanical connection to the outside rails due to the swiveling action of the motor trucks.  Paint, tarnish, plating/bluing, & lube can impede the electrical path.

Rob

[tcripe]

 Rob,

 That thought had crossed my mind, but I had already soldered the black wires from the motor cases to the "AC common" input on the ERR board. Continuity checks OK too between the wires and cases.

Terry

[tcripe]

 I think I solved it. VERY dirty wheels. I noticed that while one wheel was shiny, the others were of a duller color. Isopropyl alcohol, my usual cleaner, hadn't cut it. So I pulled out some sandpaper and went to work on the three remaining wheels. After sanding, running, picking the engine up where it stalled again and sanding, i finally have a good running engine that doesn't stall over any switches.

Terry

[Train-O]

 

Maybe, the wheels of the truck(s), with the motor(s), make poor ground connection, due to the rubber traction tires?  Parts of those wheels and other wheels, without tires, may not come into contact with the track at that precise location and cause an open circuit.

Possibly, the wheels have a protective covering, or one product is incompatible with another product.

Ralph