Prewar operating car mystery

Does the UCS look like this? If not they won't work. Don

scale rail posted:

Does the UCS look like this? If not they won't work. Don

I have one similar to that, but it's actually permanently attached to the piece of operating track.  My grandpa gave it to me with my Lionel 2055, and freight cars.

Matt

In general the couplers are grounded at one end of the coil.  The other end is connected to the shoe on that truck.  If both the right and left side are energized, both couplers should uncouple.  The operating mechanism is connected one wire to one shoe and the other wire to the other shoe. So the operation should take place when the right and left rails are connected one to hot and the other to common.  This will also cause one coupler to operate.   There are a few variations from this.  From your description I would check the contacts in the UCS controller and be sure you are getting contact.  As for the four wires coming from the controller, two are hot and common to the controller.  the other two are power back to the right rail and the left rail.  As I recall, the left wire, should be marked #1 is common.  The third wire is hot.  The second and forth wires are the two contact rails.  Using a jumper you should be able to test the tracks and car with the controller disconnected.  Hot to one contact rail should uncouple one end.  Hot to other contact rail should uncouple other end.  Hot to one contact rails and common to the other contact rail should operate the mechanism.  If this works, look to the controller as the problem.  if this does not work look at the UCS track or the car as the problem.

Yes, it is a O universal control track, exactly like that. My testing of the track as stated makes me think it is wired correctly, but each of the cars must have shorts or be misfired in different ways.

These may help ensure you have things wired up correctly.

The track is wired correctly.  After carefully diagnosing the cars, I've determined that the non-working couplers had bad or disconnected solenoids, and so replaced them.

The cars operate when power is supplied to just one shoe and the body is grounded.  I reasoned this could be caused either by a short between one side of the mechanism and the body, or the mechanism being wired incorrectly, with both inputs from the shoes wired together on one side of the mechanism, and the other side grounded.

One more clue: applying power to one shoe and grounding the body opens both couplers (once they were fixed).  Conclusion: all three cars had been incorrectly rewired at some point in the past, with inputs from both shoes joined to one contact on the operating motor and the other contact grounded to the frame.  The cars were purchased at different times from different sellers.  There must be a lot of amateur restorers out  there miswiring old operating cars!

If the two shoes are wired together, when the unload button is pushed on a UCS track, you will have a short circuit. If the operating coil common wire is touching the frame and the uncouple button on a UCS track is pushed, you will have a short circuit. Best to look closely at the cars and figure out what is going on.