Bachmann 2-8-0 wobble problem

[Tom4884]

I have a Bachmann 2-8-0 (DCC ready version) that wobbles down the track like a drunk.  I  think it may be a little out of quarter, but my questions are:
  1. How do I tell for sure it's out of quarter?
  2. How do you fix the out of quarter?
  3. Are there any other things I should check besides the quarter issue?

Thanks,
Tom

[spookshow]

Couple of possibilities -

If the screws on the bottom retainer plate are too tight (particularly the rearmost one that holds the motor), the mechanism will bind and run herky jerky.

If the frame cut-outs where the driver bearing blocks seat are imprecisely cut, the bearing blocks will have too much free play and with the end result being a lot of wobbling. One solution here is to pull the #3 drivers and apply a bit of electrical tape to the bottom and sides of the frame cut-outs. This will work as a shim and eliminate the side-to-side wobbling.

-Mark

[McKeen]

3. Are there any other things I should check besides the quarter issue?

Check that the axle bore is concentric with the wheel face. A quite common problem with Bachmann Steam.

[Tad_T]

When mine did that it was the traction tire.

Tad

[mike_lawyer]

Question, does it run smoothly with just a wobble, or does it start/stop as well?  Usually if wheels are out of quarter, the mechanism will not run smoothly and will start and stop.

I would look at the traction tire driver.  It could be that there is a problem with one of them not being completely circular, causing a wobble.

[ATSF_Ron]

Ditto on the traction tire and bottom plate screws. I’ve had that on two out of three I’ve owned. The traction tire didn’t become a problem for quite a while. Now that’s it’s replaced there’s no more wobble.

[Tom4884]

Thanks one and all.  I got diverted to other projects,  but after careful examination,  it does not seem to be a quarter problem,  but rather the bearing block issue.  I will try the tape idea and see if it helps.

Thanks,   Tom

[Bill H]

Tom;
I have a lot of Bachmann steam and one wobble area seems to be, almost without exception, lead and trailing truck wheels, they are just not sufficiently round. While you are working out the driver wobbles, see if you can find a fix for the front truck wheel wobble / out of round.

Kind regards,
Bill