Moisture around chainplates

[nestorph]

My boat surveyor commented that the moisture levels around the chainplates were higher than the rest of the deck where the levels were considered normal. Is this typical on an I-30? I don't sense this is a matter of major concern but was wondering if there are pre-emptive measures that can be taken to minimize further deterioration. Would re-bedding around the chainplates suffice? Has anyone addressed something similar?
Thanks
Nestor

[rhr1956]

I don't know about I-30 boats. Do the chainplates attach to the hull or do they attach to interior bulkheads. If they attach to the bulkheads, the same water that effected the wood core could also have gotten into the wood bulkhead. I'm replacing a bad bulkhead currently on my boat. Not much fun.

[Gary M]

It should be fairly obvious if your bulkhead is getting wet. Important to at least stop your chain plates from leaking any more.
When I got my boat the previous owner had used silicon adhesive at the deck junction. Very bad idea. I had to sand all traces of it away before I could seal it properly with 3M 4200.
At that time I cut out the inner skin and removed the wet balsa on both sides and re-glassed which of course meant taking the chain plates out. I also had to replace the Starboard bulkhead, now I keep a close eye on it since the chain plates tend to move but so far the 4200 is doing a good job.

[bvermeer]

The chain plates on the Islander Bahama 30 are known to leak on a regular basis. I lift the small deck plates every spring and re-bed them with a Sikaflex sealer. I have also used 3M5200 but it's a real bear to get off if they ever leak again. And there is enough flexing with the chainplates when sailing that they will leak again. Same as the windows! If the chainplates have been leaking a long time the interior bulkheads will be stained where the water has run down the plate and into the bolt holes, getting under the varnish. The deck is plywood cored and unless the leak has been going on for years, should be good.

Bert Vermeer
s/v Natasha
Sidney, BC

[510datsun]

I would make sure silicone has never been used, silicone won't seal with gel coat. If silicone has been used, sand the area until all silicone is removed, water will not bead up on the surface.

I use butyl tape under the small plate, in the hull cutout sealing the actual chain plate between the hull plate and chain plate. The butyl tape has very good properties for stretching and maintaining a water tight seal. Butyl tape remains pliable as when applied even 20 years later. I have re-bedded all my deck hardware, and stanchions with butyl tape. Using butyl tape is time consuming, can't get it on threads of bolts or screws, so needs to be placed on accurately, but you will only have to do it once for most likely as long as you own your boat.

My boat use to leak at the chain plate and numerous deck hardware locations where silicone, 4200, and who knows what else on my 1976 Islander 28, but now I'm leak free. I owe it all to this guys website and source for buying the right stuff!!

Check out the "Re-bedding Deck Hardware" and "need butyl tape".
Compass Marine "How To" Articles Photo Gallery by Compass Marine at pbase.com

He is also a member here on the forum, but I can't remember his user name. I did all my thru hulls as he recommends on his site, as well as the replacement of two of my port windows. I also used the "sealing Deck Penetrations" on a problem area replacing a hatch.

Always more then, "one way to skin a cat", mine is just one.

Good Luck