Pre War operating cars ----log and gondola

Has anyone ever overhauled these pre war cars?-----I’ve got a couple that don’t seem to have the strength to lift up the platform----as you know, these are tabbed together so care must be used to take them apart----is there any adjustment one can make so that platform will pop up fast? I’ve got a few that work great and would like to tune up the others I have.

Steven Douglas