I dug through a box of HO stuff I picked up at a yard sale and found an engine- Rock Island. Its obviously a cheap-o (is there really such a thing) and its not in great shape, but figured it to be great to start my kid-o out with along with his thomas stuff. Anyway, I got it out and put it on the track, andit runs... BUT it seems to not move much. You can hear it running and running hard, but the wheels dont go much. They do move sometimes in spurts and sometimes steadily and slow. I took it apart and checked the wiring, cleaned the contacts, lubed up the gears and nothing is stuck... what am I missing? Is it just hopeless? Any advice helpful! Thanks!