I have an N scale locomotive that I bought at a model railroad show. It is an Aurora/ Trix- could be forty years old. At first it would not run on the track so I used jumpers to the wheels. A little lubrication and it now runs. The armature, however seems to get very hot and there is the aroma of hot wire. Interesting that the engine runs to opposite of the other Trix locomotives, and it seems to run better in "reverse"- cab end at the rear.