Sealing Around Chain Plates

[lockie]

I have a problem with a leaking chain plate. I passes thru the deck and is glassed into the hull. I'm pretty sure water is getting thru at the deck penetration, then travelling along thru the liner cavity and emerging at a bulkhead.

Is Sikaflex the way to go? Any killer solutions here?

cheers, lockie

[rebel heart]

I use boat life caulking for it. It's never perfect and the flexing of the hull and chainplates will always cause them to leak again. Just scrape away as much as you can, tape well, acetone the surfaces, and lay down some caulking. I end up redoing it every year to keep them dry.

[matauwhi]

G'day, Mate. You can also try Sikaflex 710. It's butyl based. The same base that is used in car windscreen sealants. It's a little more foregiving with the minute movements between the chainplates, hull and deck. Cheers.

[Patrick_DeepPlaya]

We used butyl rope caulk around the chainplates where they go through the deck and then sika flex under the chainplate cover. We the butyl from New Found Metals when doing our portholes.

Here's our blog post on doing that: S/V Deep Playa - Pearson 424 : We're looking for the trash fence

-p

[Mimsy]

We are getting ready to do just this. After looking at all the options, we are going with butyl tape.

[sailingaway221]

When water gets by the sealant it can damage the chainplates and the area where the chainplates go through the hull, especially if it's a foam laminate deck. It is probably safest to take out the chainplate if it has been happening for a while, inspect it, swap it out if need be. Dig out any sealant and any soft foam / glass around it, fill it in and replace the sealant. 5200 would be fine and fairly permanent. If the water is running down the same space as the chainplates you may be very glad you pulled them out to check them. It probably isn't an easy job but if it is an old boat then you may save yourself a lot of problems down the road. I get two years usually out of 5200. It sucks to get it back out... but I only do it once every two years.

[marc2012]

Glad someone said 5200,that is what I use.marc

[Christian Van H]

Originally Posted by Patrick_Seattle

We used butyl rope caulk around the chainplates where they go through the deck and then sika flex under the chainplate cover. We the butyl from New Found Metals when doing our portholes.

Smart Patrick, really smart! We have some of that NFM rope caulk too, and it's the stickiest, most pliable stuff on Earth. Be careful with some of the Butyl tapes though... I've found them nowhere near as flexible or as adhesive...

[DeepFrz]

It is really important to inspect your chainplate for crevice corrosion and your bulkhead for rot. Also, as has been noted, your deck for delamination or saturated core.

3M 4200 or 5200 can be used, although it is easier to rebed the chainplate when you use 4200. I don't know the sikaflex number that would be appropriate but that is a good brand as well.

[matauwhi]

G'day, again mates. The advice to check for signs of corrosion on the chainplates is wise. I pulled all eight of ours 2 years ago when we were giving the boat a "birthday" (kiwi term for refit). After 23 years, 6 of the 8 chainplates had 2 ato 3 mils of corrosion out of 13. I replaced them and used the Sikaflex 710. Cheers.