they need more weight
They do not need weight!!!
The suggestions of wheel locations and rubbing on the brake gear are on the money.
I have around two dozen of these and some from the seventies! They run on my layout and the track is rough. Code 100 and 83 with 18" radius curves and wide rail joints. Wheelsets are original, brass w/plastic,proto,88 and sprung trucks(about everything).
If you have a NMRA gauge or calipers you can set the width between wheels.
I set my wheelsets to 0.74.
Another place to check is your underframe. Wheels leave a mark.
Good Luck.
Sincerely, Mark.
Try sanding your rails to make them fingernail tip smooth (Which means you can run the fingertip across w/o it getting caught on something) and then use a bright boy to go over the track. Good luck!
The problem with the Athearn RTR coal cars was found to be warped trucks. At some point in their journey from China to the purchaser, some of the trucks warped out of shape which caused the wheels to roll at an angle. The only cure is to replace the trucks.
i have problems with most athearn kits in the coal area. never had the rtr do to money reasons but messing with coal kits is about over.
Mike–had the same problem with my 6-pack of Rio Grande RTR Athearn coal cars. Not only did they derail when you looked at them cross-eyed, the couplers were also too high for the rest of my rolling stock. Switched the little suckers to Proto 2000 trucks, filed down the car bolsters a little, and they run like a dream, now. Something about those Athearn trucks–I think the whole production run needed a Priest to exorcise them. JUNK THE TRUCKS AND BURN THEM SO THAT THEY CANNOT COME BACK TO HAUNT YOU!!
Tom [}:)][}:)][}:)]
I’ve had to chase gremlins down in many of my Athearn RTR cars. I check the gauge and alignment of the wheelsets, and if these can’t be fixed, I change out the trucks for good old BlueBox Specials or change out the wheelsets with Accurail sets. I do coupler transplants as well.
None of this stuff is really ready-to-run, IMHO.