Bought a boat, and didn't check the hull. D'oh.

1982 Mako 224.

Same ole story I have seen quite often. After the second time I took it out on the water, I noticed water dripping about halfway down the keel/trailer. Figured it was the trailer. Hoped it was the trailer. Nope.

It was the keel. It was damaged.

Dude I bought the boat from had repaired this hull before. It was a different color. I let this dry for a week, and jacked my boat up on blocks so I could get to the keel. I ground out some of the old repair. When I estimated I had solid enough material left, I layered in some Marine-Tex. The problem was as I was applying it, I disturbed the surrounding glass and some water slowly began leaking out. This fubared my patch. It still leaked after that, but not as bad.

Yesterday I decided to poke around some more. As I ground away the Marine-Tex, the hole and surrounding affected area kept get getting bigger and bigger. I took some picks and a screw driver and just started poking around, picking away the crumbling gelcoat, old patch material, my remaining Marine-Tex, and the bad fiberglass. Now I have a 12 inch gouge and a 1 1/4" hole through the keel.

I think it is all solid around it now. It feels solid anyway. I hope it is now dry. It feels dry. If I fill this hole with a wood plug and some 5200, then maybe even out the void with Marine-Tex, and finally glass over the rest it may recover the boat. Gonna have to sand down a big chunk of hull though.

I have never done anything like this. I have to try this my way, or fix it at a shop and then not give my kids a Christmas.

Wish me luck.

Re: Bought a boat, and didn't check the hull. D'oh.

I wouldn't use 5200, its not compatable with wet glass. Just use resin and glass to do your repair. Wood if you need it for stiffness can be sandwiched between the interior and exterior glass but several layers of fiberglass and resin is how i would fix it. IMHO

Edit: Thanks to woody for clarifying this. By "wet" glass i meant "not cured" Duhhhh, wasn't thinking about water wet in my head.

Re: Bought a boat, and didn't check the hull. D'oh.

With that damage, it's best to pull the deck up. You likely have wrecked flotation and rotten stringers. It will also be best to do some repair from the inside.

If your boat is 24', you may be lucky and not have foam, but it still may.

Re: Bought a boat, and didn't check the hull. D'oh.

Post a few pictures and give the kids a Christmas . . . the boat can wait.

Re: Bought a boat, and didn't check the hull. D'oh.

Georgesalmon said:

I wouldn't use 5200, its not compatable with wet glass. Just use resin and glass to do your repair. Wood if you need it for stiffness can be sandwiched between the interior and exterior glass but several layers of fiberglass and resin is how i would fix it. IMHO

Click to expand...

This is a bit misleading. 5200 needs moisture to cure. The problem is not with compatibility but with adherence. It does not like to stick to a wet surface. It can actually be applied underwater but... again, the reliance of how well it would adhere would be questionable at best. George's recommendations for replacing the damage keel substructure and then re-glassing, IS the best method for repair.

Re: Bought a boat, and didn't check the hull. D'oh.

What's your location TC? Florida?

Making an overhead patch is always a PITA because of that darn stuff called gravity... but I'm sure you can do it.

I'd wait awhile to make sure everything was dried out, maybe put a small heater or fan under the damaged area to help speed drying... maybe wait a couple more weeks, the dryer everything is the better the patch will hold.

Thin goo's like 5200 and epoxies will be impossible to fill the void with because of the overhead application, instead I'd mix up a batch of really thick peanut butter filler and pack the void with that. Let it cure, then sand it smooth and to shape. Then glass over it as others have recommended. An exterior glass patch isn't going to be pretty, but it will be functional.

Re: Bought a boat, and didn't check the hull. D'oh.

This Mako has no access to the hull except in the very rear by the transom. There is a forward storage area in the deck, but there is not an access to the area beneath it. Is it possible to cut a round hole and add in one of those deck hole cover things? I am trying to include a pic with little success.

There we go. Got the image. The "channel" is a crack that was gnarly that I ground out with a drill and a tapered grinding bit.

Re: Bought a boat, and didn't check the hull. D'oh.

I really don't think it would be worth it to install an access hatch, it would be a lot smaller than you'd need it to be and you'd end up working one handed and blind most of the time.

... but, if you were to install one you may discover you have bigger issues than just a hole in your hull. Mainly saturated floatation foam and maybe rotten structural members below deck... that's a huge problem we see here with buying older fiberglass boats.

If you want to check the insides of your boat ( and I think you really should) you'll need to remove the top cap of your boat and have a look.

Re: Bought a boat, and didn't check the hull. D'oh.

That really terrifies me to think all of the innards of my boat might be rotten.

Re: Bought a boat, and didn't check the hull. D'oh.

Sorry Bubba, didn't mean to terrify you.

It just all depends on how the boat has been taken care of and kept over the years. If your boat has been kept on the trailer when not in use, that hole in the hull may not have hurt it... but if it was kept in a slip or moored with that hole it could be bad news.

Does the fiberglass and gel coat look pretty good on the top side? Are the any cracks near or around the transom? Is that hole the only blemish on the boat? If so, you're probably ok.

For right now I think you should just concentrate on patching the hole to get your boat watertight again. Take extra pains to make sure the area is solid, clean, and dry so the patch will be sound. Keep an eye on the area after you fix it and use the boat a few times to make sure all is well.

Keep us updated on your progress.

Re: Bought a boat, and didn't check the hull. D'oh.

You guys are very encouraging. I think I need that right now. The boat had some barnacles on the hull and motor when I bought it, which means it spent some time in the water.

For now, I'm going to focus on this repair. I think I will build a cypress plug for this hole. Make the hole round, fill it with cypress plug, and some sort of epoxy material. Then sand the whole thing down, make like a "V" in the hull, and fill it with glass, sand smooth, and gel coat it. Not sure what else to do.

Re: Bought a boat, and didn't check the hull. D'oh.

Seeing the pic and listening to your desires on what you want to do... Here's my 2? worth. I believe your boat is similar to this one...

If so, it is what I call a TUB constructed boat, meaning the Hull is made and then the interior sides and deck are made in one piece (like a tub) and placed inside the hull. (Like This)



These boats are usually fille entirely with foam to strengthen the hull etc.. This can make working on the substructure a bit daunting. If she were mine, I would use a semi flexible fiberglass patch (Circles of CSM and 1708 Biax Premade on wax paper) and some thickened resin to patch the hole from the INSIDE and then finish off from the outside. You should first use 60 grit paper and your fingers to get inside the hole and sand as best you can to increase the ability of the patch to adhere, then wash down with acetone. This Drawing shows how its done.

(This is and Old Drywall Trick that lends itself very well to Boat Restoration and Repair). The Poly will Set up in 30 Mins and you can snip of the wires and use PB or wood to fill in the rest of the void and then Sand and Fair. PM me if this does not make sense to you.
I will say that at some point the the very near future you should think about cutting some exploratory holes in the deck to see what issues you may have below. If a significant amount of water has been sloshing around down there for a long period of time it will have done a lot of damage to the stringers and transom that could jeopardize the safety of your boat.

Re: Bought a boat, and didn't check the hull. D'oh.

Great Idea

Re: Bought a boat, and didn't check the hull. D'oh.

That is a solid hull. You need to throw away the marine tex for this repair, grind the repair way out so you can make a 12-1 bevel build the glass back up correctly. There are plenty of examples on owners forums of this repair as well. Good luck! You CAN do it!