On a Cal 20, a lot of water can surge up and into the cockpit through the motor well, both when sailing and motoring.
We’re trying an idea I noticed on a site about the Colubia 24 and it’s motor well. We picked up a cheap inner tube for a wheelbarrow wheel, slipped it around the bottom of our Mercury 4hp 4 stroke, and moved it up the shaft. After that, we dropped the outboard in, and then inflated the tube around the shaft in the motor well area.
Two things: during our first sail, the tube did an excellent job of keeping surge out.
Secondly, when I pulled the OB a few weeks later for winter storage, the tube still was holding plenty of air to do the job.
We might try revising the installation so that the tube is simply zip-tied to the shaft instead of around it, so the tube could be replaced from above without pulling the OB, but for now we’re pretty happy. Just this morning I noticed the tube was still holding air just fine in the garage.
If others are doing this, or try it, let us know your results.