Plugging holes in the transom
 

Short history. I took out the gas tank last fall to see what was under it as far as slime and such. I discovered that my raw water washdown pump was rusted out and at 125 bucks i am not replacing it. I never really use it anyway and prefer a bucket, so 1 hole thru the transom. I also have a small live well I don't use either with a rule pump thru the transom. So I have 2 roughly 3/4 dia. holes below the water line that I want to plug up for good. What is the best way to go about this? Paul

Paul,
Tin or glass?

Glass:
What I did was get dowels the same size as the hole cut to just shorter than your transom thickness (snug diameter though I had to tap w/ a mallet) coat them and the hole w/ West System Resin... tap them in, let dry. then seal in/outboard edges with 5200..

worked for me and I had all materials on hand...

It is a glass boat. That sounds like one way. How do you get all the rubber sealant out of the holes that are around the thru fittings. I don't think anything will stick to that crap.

Mine were metal through fittings from a specialized single-beam mount. so it was clean. I just scraped the sealant from the edges and it stuck fine...

I guess you could bore it out a bit wider (but I hate doing that) OR glue some sand paper to a smaller dowel?

Yeah I am going to have to think about this one. Hopefully someone has experienced this problem.

The best way would be to take out the thru hulls, grind out to raw glass and patch as you would any hole, with a matching plug in between the two sides.

How about that Marine Tex stuff. Just filling in the hole's with that after i get all the rubbery stuff out. Can that handle a 3/4" hole about 2 inches thick? Maybe do it in stages and build it up? I have filled screw holes with it and it worked great and hard as nails.

NO! for a hole that size you need some glass in it, not just a plug. Best bet is probably one coat on the outside, filler made out of epoxy wiht some filler, chopped glass or cabosil, and then a couple of coats of glass on the inside. You don't want that plug coming loose!

I have done this many times, the best way to clean the holes is to grind with a dremel tool, till clean, don't worry if you get to raw glass!

Then like said above use a dowel of same size, about 1/2" shorter then the thickness of the transom, dip in resin to seal the dowel and glue in the hole, tap with hammer till it is recessed in 1/4 of inch.

Let dry top off hole and surrounding area with Marine Tex and you go to go!
Spread Marine Tex good so there is little sanding after, this stuff sands like Iron!!

Good Luck!

I saw Greviskis do something like that on ship shape
call me in the am and I'll explain

why not screw on a ball valve and be done with it? are you looking for a more permenant solution?

Pretty much like what was said above, make wooden plugs, soaked in West System, tap it in with a mallet. For the plug, you can even use 3 layers of plywood with expanding diameter to match the holes. 3/4, 1, 1/14 inches in diameter... I did this with my transom as well...

Paul,

I'd just get some plumbing parts to cap the fittings. Whoever uses the boat after your done with it then has holes to add washdown, livewell back in if they want.