Thanks for all of the above feedback ... I really enjoy this, learning about both the model and the prototype!

Re the coupler -- the frame vs. truck coupler explanations make sense, except why would the coupler on the front end of the loco (which is identical to the one at the rear) work totally fine hauling the same freight cars but the one at the reverse end of the loco doesn't? This leads me to think that the problem still lies with the coupler itself, which has lost its springiness and simply needs replacing. I'll still see if I can install a longer Kaydee one although the socket doesn't seem designed for the Kaydees.

Also, I tried unsuccessfully to reattach some other traction tires to one of the drive wheels. It seems almost impossible to fit the tire back onto this wheel as there is no room to maneuver. Does anyone know if there is an easy way to do this? (I had the same problem with one of my British tender-drive steam locos -- I did manage, in the end, to get the tire installed but it took a long time and was a real pain! Was also worried about damaging the loco.)

Thanks again,

Rob

You might try the "Ask the Bach-man" forum on their site -- he may be able to give you ideas on replacement parts. Depending on how good you are with styrene, by the way, it might be a worthwhile task to body mount the Kadees.

If you replace the truck-mounted couplers with body mounted ones you'll have to lower the mounting base to compensate for the large opening the tm's require. You'll need to shim it about 1/16"-3/32". I just did this to a B'mann gondola I got en the evil bay....

Here's the latest ... I've now had a new traction tire added to one of the loco's drive wheels & as well as a new coupler (replacing the damaged one).

The loco now runs much better. However, you were all right -- I have to place a freight car having a body-mounted coupler behind the engine. This now (for some reason!) applies to both ends of the loco. If the loco hauls a freight car with a body-mounted coupler, everything is fine but if it hauls a truck-mounted coupler, the freight car derails.

Otherwise, it's running great now, even at low speeds, so I'll have to have a few running sessions with it.

Thanks, Rob