I just got a copy of the November CTT and found a question on page 26 from one Mike Segna, asking how to stop a 2037 from derailing its front truck on curves. Ray Plummer gave him a long list of things that might be bent or broken but left out what may be the most important information–that Lionel’s design is faulty.
The 2037 and its ilk have the pivot for the 2-wheel front truck located much too far forward on the locomotive. The correct location is about half way between the pilot wheels and the middle drivers. When the pivot is farther forward than that, the pilot truck oversteers and, given half a chance by uneven track or a frog, will derail to the inside of the curve.
When I was a kid, I gave up on the pilot truck of my 2026 and just removed it. Much, much later, when I understood the problem, I lengthened the tongue of the truck and drilled and tapped the front crossmember of the motor for a new pivot in about the right place. I haven’t had a problem since.
I have the same problem…But only on one switch curve, and only in one direction. I thought it was something with the switch. The wheels seem to jump right off the track.
Your post is very timely, probably a lot of these problems going on. Have you seen that the positioning issue you discussed is unique to the 2037 and related engines. Or is more common? I too am having a problem but it seems worse due to the randomness. Only happens occassionally mostly one engine at one switch. So I am more suspcious of the switch. Possibly not level? Trying to determine. Also thinking that the speed that the engine is moving may cause the inconsistency. Going to spend some time on it. Similiar problem with 3 way Ross switch but that I’m sure is a horse of a different color.
Another problem not mentioned here is that the Spring that fits around the Rivet on the front truck should be strong. If it is weak that will cause derailments as a weak spring will not press the front pilot wheels to the rails as such to avoid derailments. The 675 & 2025 Engines had the same Pilot Trucks with no Ill effects as well.
I have a 2026 and a 2037 (both belonged to my dad when he was young). I took them in for service a few years ago, and one was missing the pilot truck. When I got it back it derailed like crazy. I took it back to the store and he checked the gauge. It was off by 1/8 inch. After adjusting the gauge, it ran fine.
We also weren’t able to duplicate the problem in the store, but the layout in the store used wider curves than what I was running at home.
I wonder if it could be that if everything else is perfect, the design flaw is minimized?
You’re right of course, Dave, that having everything in perfect adjustment greatly improves your chances. And the layout design has a big effect too. I used to have a 45-degree crossing at the end of an O27 curve, with the crossing shortened to put it pretty close to the curve. The 2026 never could make it through that crossing, no matter how much I tweaked the track and the locomotive. That’s what led me to discover the geometry problem.
A further handicap that is unique to the Korean-War 2026 is the outsized middle drivers. The pitching of the locomotive on that uneven wheelbase probably doesn’t help with keeping the front wheels on the track.
A pretty good rule of thumb for the optimum pivot location is as I described above–about midway between the pilot wheels and the center of the drivers. This location will align the pilot wheels with the track ahead, regardless of the track’s curvature. Any closer to the drivers and the pilot will understeer; any farther forward and they will oversteer, as in the 2026, 2037, etc. You can easily check any other locomotive with a 2-wheel leading truck just by eyeballing the pivot location.
I think it’s interesting that your dad’s locomotive was missing that truck. I’ll bet he took it off to solve the problem as a kid, just like I did. I don’t know why I still have the truck for mine. It should have gotten lost long ago.
Bob, if you are correct about your design theory wouldn’t all of them act badly? Like Jumijo, I have several 2037s and similar engines and have never had such trouble-- not with 022 switches, fastrack switches, crossings, or even 027 track. In fact, the 2037 is one of my favorite engines. My “runner” will haul more cars up a standard Lionel trestle grade than my 682. Altho I haven’t had to experiment, my guess is that the wheels being out of gage or too weak a spring are the more likely culprit(s). Your solution of removing the truck would certainly cure all of those causes in one swoop, but doesn’t pin down which one it might actually be. That type of troubleshooting is like dropping a new engine into your car to fix an elusive noise.
Lionel sold a bajillion steamers of that platform; if they were so troublesome I doubt they could have done that.
No. The steering-geometry error doesn’t necessarily make any locomotive derail. On tangents, on smooth curves, and on gentle curves, the pilot wheels probably won’t climb the rail. But when there is an irregularity, like a frog, on or near a curve, having the wheels angled to the rails does make a derailment more likely. And the tip-off that steering geometry is involved is that the derailment is almost always to the inside of the curve.
I wasn’t proposing removing the truck. That’s what I did in desperation 50 years ago. What I would suggest to anyone having this problem is to observe whether the derailment is consistently to the inside of the curve. If so, and if there is no other obvious fault in the locomotive, my experience is that moving the pivot to the rear will do wonders.
Good info! I never thought derailing to the inside/outside…if I ever have a problem I’ll be sure to note the direction and see if it’s consistent like that. For now, my only derailments occur when backing a train thru switches–knock on wood.