I know these engines have been out for quite a while, mine ran good most of the time. I did have trouble at one place on my layout when running very slow. At this spot sometimes the engine would stop sometimes it would loose the sound. I finally got around to checking for the problem and found the most forward and most rearward axles on the engine are spring loaded, or they should be. It turned out the springs on one end had no memory the axle on the other end did not have enough clearance for the axle to move up and down. I replaced the dead springs with a couple springs from an old HO freight car and removed some of the material from the bottom plate that retains the axles, problem is now gone.
Ray
