Probably one of the tender trucks have rotated and cause the conducting wheels to be on the same side.
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
My bachmann Spectrum 2-10-2 jumped the track and fell about 4 feet to the floor and now acts as if it had a short. I have removed the cab and tender cover and if it's on the track and I tilt the tender so that the wheels on one side only are touching the track it seems fine (has sound, lights, runs forward and back) but as soon as I let the tender down so that all wheels contact the track it shorts out. Any ideas?