I really enjoy using my Lionel postwar No. 3662 operating milk car, but lately I have found this great car is giving me some trouble. Specifically, the milk cans never come all the way down the chute. One or two of them get through before they get jammed. What do you suggest to fix things? – Vince Liguori, Buellton, Calif.
Are you using original cans? The 3662 cans have been reproduced. Some are perfect, but some are dimensioned wrong and can cause jamming. Since the chute is plastic, there is seldom a problem of it warping, as can happen with the die-cast metal chute used on the earlier and shorter milk cars.
Roger Carp discusses the 3662 car in his video: https://www.trains.com/ctt/videos-photos/videos/how-to/collectors_showcase/professor-carp-episode-10-lionel-automatic-refrigerated-milk-car-and-platform/
Learn about the No. 3672 Bosco version of the milk car: https://www.trains.com/ctt/how-to/timeless-classics/lionels-automatic-refrigerated-milk-car/