I have obtained the above listed engine through Ebay. When I place it on the track it does not run. However if I lift the engine so that the rear drive wheels are not on the track the motor runs great. I looked at the rear wheels and they have Drive bands on two of the wheels but they are on opposite sides. On my other engines that have these bands on the wheels, the wheels with the bands are on the same side.
Question is: should the bands be on the same side of the engine and if so how do I release the wheels so that I can reverse one of the wheels?
It sounds to me like one of the rear axles is in backwards. If you can remove the bottom cover of the rear truck, you can turn whichever axle is different than your other F units and see if that helps.