Operating Lionel cars, post war.

[Charlie B]

I have a question for someone about these cars. When I place them on the uncoupling/unloading track when I use the unloading button the coils to the couplers energize also and draw power from the operating solenoids. Is this normal or is there something going on I should look at. These cars are from 1948, the year before magnetic couplers. I haven't been able to locate a simple explanation of how the uncoupling/unloading track is supposed to work. Anything would be a help.

Thanks.
Charlie