Lionel PB&NE SW1200 Diesel Locomotive #42 derailments

I just got a new diesel a few weeks ago and it would derail when it went over my Ross custom Switches, watching it closely going over switches I saw the very front wheel on one side would jump over the curve of switch . I turned it upside down and looked at front axel and front wheels. There is a spring mechanism under each wheel near axel and wheel. Pushing down on wheel on one side , the wheel and axel would spring up and down. The opposite side would not spring, it would just stay down. So it was unbalanced. I put a small shim under the axel next to wheel on defective side and did a test run . Ran perfectly, no more derailing. Sent back to Lionel for new front axel. Under warranty. Double check your front wheel/axel spring.

@dtrain66 posted:

Hi all, let me start by saying I'm a new poster here, but have been following this forum for many years. The information and inspiration is incredible. Here is my dilemma, I recently purchased the new  sw1200. The detail is great, love the strobe light. I un boxed and programed an engine #, ran it around the layout by itself and it was flawless. I coupled some box cars to it and they derailed instantly through any curve. My minimum radius is 042. I tried a heavier car with the same results. My first inclination is that the coupler centering spring is to heavy. Thoughts / ideas?

That's very strange indeed. I have the same engine, and it is a great runner.

Dumb question, but did you take all of the packaging material out? I'm fairly certain there was card stock packed between the trucks and the frame.

Any chance you could post a short video to help us help you?

Thank you Tony, I will take a second look.

I am confused with the video provided, in that the video shows what appears to be a loco with three axle trucks. The Lionel SW1200 in this case with PB&NE markings as described earlier has two axle trucks. Am I missing here? Could you please confirm the loco type in the video.

Thanks

Hi Dennis, that’s my Lionel 2233151 Legacy diesel DD 35 1650. That engine is 22 inches long , that’s why it has three axels trucks. Because you said you were having derailments, I just thought you should check your wheels for defects. Maybe it’s not a good comparison with my engine.

Maybe check the coupler on the locomotive to make sure it has enough swing and is not binding or hitting anything (like low hanging steps).

I've got the SP version of that switcher and have had no problems with it.  It is a great switcher and runs like a champ.  I've pulled 10-15 car freights with it and went thru the yard tracks at the club (Lone Star HighRailers in Grapevine, TX) with no problems or derailments, unfortunately our club uses the Ross Switches but I've pulled and shoved the same cars thru them and have not had any derailments with the cars.  Everything works great.  I won't go into why I don't really care for the Ross Switches, they are a good product and very well constructed, we have probably 25 to 30 of them on the layout, they are used by TWTrainworx, very well known custom layout builders here in the DFW area.  I'm not really sure what to tell you but I'm sure you will get some great answers, I'd definitely check around for something stuck up underneath whichever truck you are having the problem with.

Best of luck.

The fact the OP says the engine - by itself - ran flawlessly around his O42 curves would lead one to think the issue has something to do with the loco's trailing coupler, thereby causing his boxcars to derail.

@dtrain66 - Question - Have you coupled the boxcars to the engine's FRONT coupler and then 'pulled' the boxcars in reverse?  And if so, do the boxcars still derail?

Hello all,

Thank you all for your input. I did check all of the suggestions and didn't find anything unusual except that the centering springs are slightly stiffer than those on my other locos. On a whim, I weighted down a gondola to NMRA standards for O scale and guess what? Problem solved (sort of) it went smoothly around the layout without a hitch. I will weigh down a few cars to use as lead cars in a train. Maybe over time the springs will weaken enough to not have to do this, but in the mean time I'm a happy camper. This a great little switcher that I'm glad didn't become a shelf queen. BTW this thing puts out so much smoke  I had to turn it off. Couldn't see the other end of the train room after a few minutes.