I just recently re-powered with a Beta 14 and Seaprop60. After 5 hours of operation my prop fell off. I know that I tightened the bolt into the cone, very tight. A 16 inch piece of pipe on the end of the hex key. The manufacturer does not say anything about threadlock. When I put the new prop on what do folks recommend? I have certainly never had to use anything on my Volvo Saildrive. And while I am at it...anyone have experience using threadlock underwater?