Knocker Style Prop Puller Question

[markcr]

Does anyone know how these devices work? I need to pull my prop and got one sent with my new OJ. It just looks like a large brass cylinder with threads cut into it.

[kaneboats]

Yup. You screw it on tight and smack it with a hammer. It sends a vibration up the shaft and back down. It's supposed to "pop" the prop loose. Be careful.