Post War 2025 derailing

I have a PW 2025 2-6-2 Locomotive that runs great and negotiates all my O-22 switches and O-31 curves well when it is running with nothing but the tender. When I add a few cars it tends to want to derail in the same spot on a curve. I have another PW 2055 4-6-4 Locomotive that will pull the same consist of cars (and more) through the same track with no derailments. I am thinking that the wheels on the tender or the coupler might be out of alignment or not rolling freely. Any other ideas?

Mitch[:D]

Mitch : can you tell us exactly which wheels derail, and where is it derailing at exactly also. This will help getting some solutions, I think !
Thanks,

You didn’t say whether this is a prewar or a postwar PW 2025; but I’ll assume the latter…:wink:

Lionel used a 2-wheel pilot-truck design whose tongue was much too short. The result is that the truck will oversteer significantly on curves. It is possible that this, combined perhaps with some irregularity in the inside rail, could be causing your problem. If this is the culprit, the pilot truck will typically derail to the inside of the curve. The difference between running light and pulling a train could be that the drawbar pull of the train swings the front of the locomotive out farther to the outside of the curve. This moves the pilot-truck pivot out also and exacerbates the oversteering.

Both locos are post war. I have a very tight layout due to limited space, There is a straight part of a switch then a half straight then two O31 curved sections. It always derails on the inside of the curve and it seems that it is most often the rear drivers on the loco and then that causes the wheels on the tender to jump the track. It even happens at pretty slow speeds (as slow as I can get the train to run and still move).

My uncle that I inherited this set of trains from had added extra weight to the 2257 caboose many years ago. I tried taking out the extra weight but that didn’t help. For a while I thought it was an orange Baby Ruth boxcar that was coupled right behind the tender that was the problem, but when I switched out the boxcar and ran the train without it, it still happened.

Hope someone has an idea. It is a sweet little steamer but it looks sad running with nothing behind it.

Do you think I should pull up the curved track and replace it with two new sections? The track is new O31.

When I have had trouble spots like that I’ve shimed the track at the point of derailment. Just a small piece of wood or plastic under the ties. If its derailing to the inside I think I’d shim the inside ties. Doesnt take alot of height. The rail might be deflecting just slightly under the weight of the engine.

Not sure if this will help but try cleaning the drive wheels on the locomotive.
Lee