Plugging lock pin hole

Had shake down run with New Toy last evening. Got main up and had a nice sail. Wind about 12 kt and gusts. Appeared that had done all rigging correct and no problem. Lowered and raised keel upon return OK. The only known problem was the water I took on from the lock pin hole. Question? What is the best way to seal off this hole since I have to lower and raise keel each time due to chanel depth in Tahoe Keys. Lake Tahoe was choppy so I guess a lot of spashing into the keel box. Had an 1-2 inces of water in galley floor after about 2 hours. Remember someone saying cork. I'm wondering about using silicone to secure a rubber gasket on both sides. Any thoughts will be appreciated. Thanks.

Ken

You are talking about splashing, not a lot of pressure.  I run in salt water so use non-corrosive materials at all times.  Buy a plastic electrical box cover.  They make them with holes for switches and outlets but also as solid blanks.  Cut it in half and sand the back side.  Glue one half on each side of the keel well with silicone calk/adhesive.  That should solve your problem. 
I'd also suggest you look at the front edge of your keel well when she is on the trailor.  What you have sounds like what I've seen after the keel broke a hole in the front of the keel well.

Hello ken,
i have a CM21 I'm about to restore ill look in to some solutions for you to make a more permeant fix.

Looking at my holes, it looks like they were filled with silicone adhesive.  Really simple.  Don't know if this is working because I also have / had a hole in the front of the keel well that isn't completely sealed yet.