Other idea, is to carefully remove that grease tube, and clean it out, then put Permatex Aviation sealer on each end of it and the threads of the grease fitting when replacing.
http://www.crowleymarine.com/johnson-ev ... mdl=JUWWD2OMC version but Volvo is the same. Part # 68 in the diagram....
The only places that you can really get water in the bellows are the bellows itself, and the attachment points on either end in addition to the grease tube.
https://marinepartseurope.com/en/volvo- ... 10670.aspxEuropean VP catalog. their US catalog on
http://www.volvopentastore.com is maddening to navigate!
Seriously consider an outboard for your next boat. You'll be far better off. In the future I'll keep my Chevrolet small blocks in hot rods, in boats I'll take an Evinrude!