I discovered this while replacing the wiring on a milk car(non magnet cans). I wiped something off the floor of the car thinking it was dried grease or something. Afterwards I couldn't get it to work smoothly as it did before. I tried all the suggested repairs, but it would not eject the cans properly, either it would shoot them out or drop onto the track, depending on the voltage. That's when I remembered the substance I wiped off the car floor. I tried to duplicate the consistency of whatever it was. As far as I can tell it was common wax. Anyway wax did the trick. I was having the same problem with another car that uses magnetic cans. Wax fixed it also. Some how it allows you to use enough voltage to push the cans out onto the platform smoothly and controlled, instead of falling onto the track or ejecting them way too fast. Good luck.
Chris A
