So more experimenting was done since my last post. The building was adjusted to different distances from the track. The instructions indicate 1/2" between the side of the building and the side of the reefer.
More than two milk cans and the next one tips over. The brand of milk cans doesn't seem to matter. I noticed that Lionel cans do not have the sharp edge on the bottom like the K-line cans do, so I figured they wouldn't tip over as easy. So far that is true, but I still can't load more than two or three cans.
If I load the cans by hand, I can get four or maybe five in the car.
More testing is called for. And if that doesn't work, I'm going to take the body off the reefer and have a look at the workings.
There is a video on Youtube showing the car in action with the body removed.
