E32-200 How a Propeller Connects to an Engine

A beginner’s note for myself/for future reference: A quick overview of how a propeller shaft attaches to both the engine transmission and the propeller itself. Mine is currently out of the water and disassembled and so it is easy to view.

The coupling bolts to the transmission and within the coupling is a key (male) protrusion into the cylinder. The rusted condition of my coupling is less than excellent...