Thanks for all the responses guys!
I did some more testing this morning and have some interesting news. I opened the engine up for probably the 5th time, removed the drive shafts and re assembled it. I did this so I could rule out electronics and motor problems. I was able to push the engine around my layout by hand with the worm gears removed and motor disconnected. I was surprised to discover that it had only very minor stiff spots, which seem perfectly acceptable.
Now I'm really confused because the fact the behavior is so different on uneven track really pointed toward axle problems. There's likely a sideways force created by the worm gear and helical gears which is causing the axle shaft to be forced to one side. I was wondering about that all along but wouldn't that sideways force be a problem all the time? not just on uneven track? it seems like track wouldn't effect that at all. I have the same feeling about control problems. I think they would be more consistent.
John, interesting the shims lasted so well! Adding a temporary shim like that probably going to be my next test. I'm more confused now after testing this morning. It sounds like with the ERR cruise there will be some speed discrepancy then, but that's ok. I do like to run lash ups though. The entire reason I got this project was because I couldn't find a Legacy Allegheny for sale anywhere.
Joe, Thanks for the info and video! I'm still convinced based on the bucking that something is grabbing somewhere.
Ken, No the lights stay on very steady. I've had the engine apart 5 times now and it's super simple and spacious inside. I'm convinced there's no loose wires. And the engine wheels aren't even worn smooth yet! They're shiny and new just like the rollers. Which raises another question... do you guys think this thing might just loosen up a bit with more run time? I mean it runs as I would expect it to 90% of the time.
Dave, No I removed those right away when I got the engine. They were rubbing. But they've been off the engine for 3 weeks so it's definitely not those
