Annoying Bachmann diesel problem

[emdgp92]

I was given a used N scale Bachmann F9 over the weekend. It's not in that bad of shape, and runs pretty well. However, it's not without its problems. Lately, it doesn't run very well with the rear drive shaft in place. For some reason, it causes the worm gear to bind. If I take that shaft out, it runs fine. However, I'd like to run it with all 8 wheels powered. Does Bachmann still have parts for these? If not, any other ideas?

[jeffrey-wimberly]

I had a similar problem with a Bachmann N scale F unit some years ago. The worm gear was binding because the teeth were stripping. I replaced the worm gear and the top gear in the truck and all was fine.