@Doug Troeger posted:That's great to know!
The track is ok - none of my other engines have problems - and I think the pilot is properly gauged. What about the drivers? When I put this beauty on the tracks, there is almost no lateral play - which (i) I guess to be necessary for navigating the turns, and (ii) is present in all of my other steamers. The play in the rear driver is about half the width of the driving gear, but there is essentially none for the front pair. The symptom is that the front drivers climb the rails (Lionel tubular) and then derail upon entering a curve. I am proceeding cautiously here (engine with some serious sentimental value), but does it make sense to try to push the front drivers a bit further apart? Am I correct in thinking that the lateral play is necessary? And if so, how much should there be?
Many thanks,
Doug
It's more likely the opposite is required. The drivers being mounted too far apart are causing it to climb as the radius of the curve is tighter than the space required by physics to make the curve without binding. This problem occurs quite frequently if a locomotive is being re-wheeled by someone who is lacking skill. It needs to be checked on curved track before returning it to the customer.
If they are mounted too close together, the loco will "hunt" or bob back and forth sloppily as it runs down the track. You would see it more on long straight sections.
So the solution "could be" the drive wheels need to be pressed on closer together. We could be talking about mm's here to make it right. If your wheels are original to the piece, they could be swollen and expanding due to die cast failure. The nickel tyres or rims maintain shape, often causing the die cast wheel to bow outwards ever so slightly as it "grows" or expands. You may not even realize your wheels are doing this, as it could be such a minor amount that it doesn't become noticeable until you have operating issues.
Hope this makes sense.
