The seacocks for the cockpit drains, and the galley sink have been weeping since we've owned Surprise! I got tired of honing them and having them leak withina month of launch. So this haulout, I decided to replace all the thruhulls and seacocks. I chose Groco thruhulls and seacocks.

During the process, I eliminated the abandoned holding tank pumpout thruhull, and the head inlet and outlets. We've never boated in an area that allowed overboard head pumping. If I ever take an extended offshore passage, there are other ways to get the poop into the water.

Here are the original installations.

Starboard cockpit and galley sink drains

Port cockpit drain

Engine water intake. The engine water intake did not have a seacock - just a ball valve on the stem of the water inlet strainer.

Head inlet and outlet - sink drain

I removed the thruhulls by cutting the rims off with a cutoff wheel.

The original seacocks are the Wilcox Crittendon type, and were only held in by the threads of the thruhull. What I thought was resin "gluing" the flanges to the hull was merely caulk. It smells like plumbers putty. Even after 28 years, the caulk was still soft.

I was concerned about using wood to mount seacocks. So I made the mounting blocks out of fiberglass. I molded them 5/8" thick, with an outside diameter big enough for the seacock to set on. I bored the appropriate size hole for the thruhull in the centre of the block.

I sanded the back side to fit the hull, and attached them with epoxy putty (ground glass in West System epoxy). I waxed the thruhulls and seacocks and used them to hold the mounting blocks to the inside of the hull - just finger tight to hold the blocks in place until the epoxy set. I aligned the seacocks so that the handles would be in a good position and drilled the holes for the mounting bolts. I then removed the seacocks and thruhulls. I painted over the mounting blocks with white gelcoat.

I inserted the thruhulls into the outside of the hull and screwed the seacocks onto the thruhulls. Both are sealed with 3M 5200. The final step was to install the mounting bolts.

The newly installed seacocks complete with new hoses attached:

Starboard cockpit and galley sink drains

Port cockpit drain

Engine water intake

Head sink drain