My polyethylene Pyranah ORCA has bulheads that leak excessivly. I confirmied this on land by pouring 1 gal of water into my cockpit and then raising both ends of the boat. Watching through the hatches I could see the water flow into my bow and stern compartments. Is there a recommended sealant I could try? Does anyone have experience with silicone caulking as sold in the hardware store? I transport the boat using a rooftop cradle system and store it on its side suspended from webbing slings. Any hints, recommendations, or experiences with this type of repair would be greatly appreciated.
Do not use silicone!
Silicone sealers are weak and leave a residue that inhibits bonding with anything else. Lexel or one of the GOOP products is the way to go. You could also use Sikaflex or 3M 4200/5200.
I’m using E6000 on my fiberglass boat with ABS plastic bulkheads. It’s from the GOOP family (Eclectic Products, Inc.) of adhesives. You can find it in craft stores. It seems to be doing the trick, but time will tell. E6100 might be a better choice as it has lower viscosity.
What you need is a polyurethane based adhesive, Sika-Flex or similar, But the secret is in the preparation and here is where it gets complicated:
Some Orcas had foam bulkheads, No problem use a plumbers blow torch to quickly pass over where the hull and deck meet the bulkhead, the aim is not to melt either plastic or foam, think of it as using the flame to clean the plastic. Now seal with the PU adhesive
Other (latter) ones have a plastic bulkhead that despite being a different colour to the inside of the kayak is the same Polyethylene material these can be flame treated and sealed the same as above.
The worst of the three common types used an ABS bulkhead in the polyethylene kayak shell. This is the worst combination of the lot because it looks like the PE bulkhead above but flaming won’t help the adhesive adhere to the ABS. it needs a special primer on the ABS and flaming on the PE as above, the primer is hard to get (contact the adhesive supplier). Probably the best solution is Lexel although from my own trials this doesn’t hold up as well as flaming and PU’ing done correctly. Resulting in the need to redo every couple of years.
I Hope the above is of some help
According to Eclectic Products…
…the difference between E6000 and the GOOP line is the solvents in them. Other than that, they’re the same.
we’ve used Marine and Plumber’s Goop with great success in PE boats. Do make sure do remove all the old stuff and clean out the sand and make sure everything is bone dry to start. Seems like Goop has enough flex to take the expansion and shrinking that come with temp changes and plastic boats.