Setting/Context:
31x51 RealTrax OvalZ-1000 Transformer and Controller
RailKing Santa Fe F-3 Boxed Set Item No. 30-2701-1 (A-B-A set, two powered A units)
Both powered units ran fine out of the box for 5-10 minutes then started acting-up, jerking, lights dimming, unable to go into reverse, throwing circuit breaker on transformer. The set was pretty much innoperable at this point so I disconnected the trailing A-unit and just ran the lead unit to trouble-shoot.
With only locomotive #28 (lead unit) on the track.
1.. Turn on power supply, throttle up about halfway, the locomotive appears to be in neutral, but I can gently bump it and it takes off. Sometimes it jerks a bit and trips the circuit breaker on the power supply. 2.. On those occasions when it does seem to start-up normally, shift into forward, and start moving with a slow crawl. it eventually proceeds to jerky, sporadic accelleration, head-light dims (or not on at all), and Proto-Sound brakes squeal as if I am throttling-down even though the throttle is constant at a ¾ setting. 3.. If and when I can get the locomotive into neutral, and switch the unit into reverse, it struggles to move and will eventually trip the circuit breaker on the power supply. Sometimes I can give it a little nudge in reverse. when I do, the front wheel sets spark a little and the power supply circuit breaker trips.The track and wheels have been cleaned with track cleaner, the black center rail is polished and clean. I have no problems running my brand new RailKing 2-8-0 Santa Fe Steam Engine Item No. 30-4119-0 (Loco-Sound) in nuetral, forward, reverse, whistle, bell, etc. on this same set of track and power supply/throttle. The track, transformer, controller, and 2-8-0 RTR set is brand new, just purchased in December.