Seam sealer for OK scupper holes?

-- Last Updated: Apr-19-05 11:13 AM EST --

My Ocean Kayak Yak board seems to have a slow leak, pretty much since the day I got it. It is mostly noticeable when I use it in surf. the hull fills with maybe half a cup of water over a day of using it. I think the leak is probably a factory defect from a seam where the scupper holes seal to the bottom of the hull. Can anyone recommend a good compound for sealing the seams?

half a cup?
Half a cup a day is nothing. I wouldn’t even bother with it. There isn’t any sealer that will adhere to polyethylene, but if it really bugs you try some good duct tape. The only permanant way to fix it is plastic welding.

Could be more.
I’m taking it out in the surf this weekend, so I’ll measure it at the end of the day.

OK Leaks
If it’s a half cup it’s no big deal. Condensation could cause that. My wife’s Frenzy had that problem. I never could find a leak. However 3 of the 7 OK boats I owned did have leaks at the scupper holes. Plastic welding is the only thing that will work to seal it. If you find a pinhole I’d return the boat for a new one. I did fix one of the leaks by using my camp stove a spoon and a plastic welding rod I got from OK. It was a little ugly but it was inside the scupper hole so not easily seen. Only reason I did it myself was I got tired of screwing around going back and forth to the dealer.

My Yak board is the same way.
…and has been from the day we got it.

I think it gets in where the grab handle is attached.

I have to dump it after about every third big wave.



Somebody correct me
if I am wrong, but aren’t Yak Boards rotomolded? If so, there is no “seam” at the hull, only a mold seam mark. Possible leaks would be at the strap eyes, or even a poorly installed drain plug. Of course, there could be a defect in the molding.

That’s my best guess.



– Last Updated: Apr-20-05 11:13 PM EST –

It's mostly the strap eyes where your seat and thigh straps attach. For one of these boats half a cup in a day is not worth worrying about. If it leaked more you can drill out the rivets and redo the strap eye attachment, caulking first with silocone sealant and then making sure you do a first class job of re-riviting the strap eyes. From my experience the scupper holes are probably one of the strongest parts of the hull, I doubt the "seam" is leaking there, you can fill the boat with water but I would be carful about stressing the hull while checking for the leak. As stated elsewhere its not really a seam but maybe a pin hole leak where it adhered to the mold in a funny way.

They have places that LOOK like seams where the clamshells of the mold meet. But the blown-in poly pellets melt and smear all over the inside surface of the mold on injection, forming a seamless inner skin on the mold. There is no seam for the RM boats of the world, whether they’re SOTs or SINKs.

And it probably is the fasteners, or in a number of cases, the hatches. You can re-attach the webbing & strapping with new, slightly larger pop-rivets, try to sqeegee in some silicone sealant from around the edges of the underside of the straps topside, hit them from inside (those you can reach) the yak using the hatch(es) as an access point(s), or tighten down your hatches, or put a new sealing ring on the hatch edge’

Or you can live with it.

Half a cup is nada, friend -just be sure to not let it sit inside & ferment ;> Drain what you can, put a little -a LITTLE -bleach in to control the mildew and mold and creepy crawlies from time to time, and enjoy your boat. BTW, after you put the bleach in and close the hatch and let it work with the boat sitting out in the sun, please don’t open the hatch, stick your head in, and take a big breath… Let the boat air out & breathe itself, first!

I get about that much in my Old Pro, and Sally racks about as much in her yak after an outing. Biggest source of water was old sealing rings on the old hatches -replaced with slit, small diamter, glued on & glued-together pipe jacketing material from Home Depot -worked like a charm, can now tighten hatches down just fine.

A half cup? DOn’t sweat it -that much water really won’t affect the way you


_frank in Miami