Bachmann Santa Fe 4-8-4

[jonjdurkin]

This loco runs exactly 2/3 of the way around my 8x8 layout and stops in exactly the same place each time (on a straight track, not a curve). It still has power (headlight works) and a gentle push gets her rolling again but she stops at the same place each time. I have run a Niagara, UP FEF, and SP GS-4 on the same tracks with no problems. I have also tested her operation on a roller track and she runs flawlessly. What do you think is the problem?

[Doneldon]

jon-

Does it stop at a rail joint? If so, you may have a high rail. However, a more likely problem is dirty track, possibly exacerbated by not having a nearby feeder. And/or, you might have poor electrical conductance to that track section if the track has been down for a while and you are counting on rail joiners from adjacent rails to power that piece.
                                           -- D

[jonjdurkin]

I cleaned the rail and wheels on loco and tender-they weren't very dirty. As I mentioned in original post this is the only loco to do this-all others run around the track flawlessly. The loco runs continually on roller track and changes speed and direction without a hitch-but when I put her back on the regular track she stops each time at the same place. What's up?

[Barney R]

Jon-
I am having the exact same problem with a 4-6-4. So far - I have cleaned the track. Replaced that section of track with new track. Added additional power feeders. Changed the decoder.
I have not figured it out yet, but I will keep looking and checking and reading these forum post, looking for other ideas and solutions.

Barney

[bobwrgt]

If it is DC/DCC check the harness between engine and tender and make sure they are pushed in all the way.
When it stops turn the power off and also check to see if the linkage rods are locked up or the valve gear.
Use a toothpick to see if all rods are free.
If you can get to the spot when it stops using the toothpick with power on and touching each set of wheels you can see if it is a linkage or power problem.
If they are the Dcc/DC model You may also have bent wipers on the drive wheels not making good contact with the back of the wheels.

Bob

[Barney R]

Jon- My problem turned out to be dirt on the wheels of the tender. I would have sworn that I had already addressed that item. I have been working on this for a while. I would get frustrated and put it away for a bit and then go back and try again. It is running just fine now.