1940s WWII Army Military Federal Electric Co Hand Crank Air Raid Siren Original

Description

This siren is complete and all original. I can't figure it out, it was gummed up with accumulated dirt and grease, so I cleaned it up and relubed all the gears. Both sides spin freely when it is apart, but when I put it back together it locks up. I don't know if the gears are in the wrong place or what. It's a nice piece, there is a dent on the front cover and rust on the cover's interior, otherwise clean.