Holes in the boat!! Installing thru-hulls

The saildrives are designed to suck water through the openings for engine cooling.  But this is where a lot of the corrosion is introduced and the openings get clogged with shells and debris.   Lots of folks by-pass this mechanism.  Simply put a hole in the boat and let the engine suck the water directly from the sea.

So, that's what we're doing.

The parts finally arrived and we made short work of it.

Here is the actual part.  It's called a "thru-hull" or a seacock.    (We have two of these, of course, one for each engine).

For those of you interested, it's Forespar  p/n 931133 and elbow p/n 901001.

First, Duane marked the area where he wants to install it.  The greenish object is a 3/8" thick piece of fiberglass that will be the backing plate to stabilize the installation.

1 1/8" hole cut in the fiberglass.

1 1/8" hole cut in the boat!!!

Hole from the outside of the boat.

We sanded the area around the hole to assure that the adhesive would have a good surface for bonding.  Certainly don't want any leaks!!

Sanded outside.

Next we did a "dry fit".  I marked the spot where Duane (on the other side of the hull) said was the perfect alignment.

The shaft needed to be shortened, so a hacksaw  was used (we didn't have any power tools although several times "wish I had my .......from home" was uttered.

 Next we applied 3M 5200 adhesive to all of the parts.  If you're not familiar with the product, let's just say that it's very "sticky".  It's the go-to sealant/adhesive for underwater projects.

All sealed up from the outside.

And all sealed up from the inside.

Then we applied some epoxy paint to the sanded area on the outside.

And painted the inside too where the sanding exposed fiberglass.  Duane ran a new hose and we're ready for the new engines now!!!  (And remember, the was X2, one for each engine.)

Last thing we did today was to apply a couple of coats of bottom paint to the area.  Tomorrow we'll install a strainer and we'll call it finished!