Caprail leaks

I am cruising in Cuban waters at this moment and I will be cruising till the end of April, then be on land for the rest of the year. On another note, after a very nasty overnight of sailing (30 knt on the beam, sea 10 ft) off the Cuban coast, I noticed that I had water seeping through the joint hull to deck. Is it a common problem of the aging Corbin or is it a rare occurrence? I already re-caulked all the fasteners at the joint. What is the fix for this problem? Valois Nadeau, (#096, Giva).

a. Wow, that is a first. I thought the hull to deck joint was done at the factory……..maybe Marius has some comments. My bet would be the chain plates deck seal are leaking. I have had to dig all mine out and using 5200 I refilled the recess and reinstalled the cover plates…..no more leaks !! Jeremy P. (#101, Two Pelicans).

b. My preferred fix is to take off the toe rail, sand/grind the joint surface beneath and then run a 2 or 3 inch strip of fiberglass over the joint. Fill the surface, fair it and then paint. You will then have to re install the toe rail. Although you will still have the holes created by the bolts that hold the toe rail down, you will have eliminated the vast number of hull/deck thru bolts as sources for water leakage. If you don’t have the time to lift off the whole toe rail, be sure to fully renew the caulking around the edge of the toe rail at the point where it meets the hull/deck. Use a quality caulk with a good UV resistance. I’m sure West Marine, Cuba (!!) will be able to advise. All the best, Charlie G. (#066, Pinguescence).

c. Valois, (1) Here is what John Neal said Solving Caprail Leaks “Hull to Deck Joint: There are several methods of attaching the hull and deck of fiberglass boats. The most common method utilizes bolts or screws protruding through on the inside of the hull to the deck joint. This a mechanical clamp joint is relying on the bond of a sealant adhesive (3M 5200 is often used) to stop leaks. After eight to 12 years and several thousand miles of ocean sailing the sealant/adhesive loses some of its elasticity. Due to the working of the boat and the different climatic conditions the toerail and hull expand, contract and flex at different rates eventually weakening the bond, allowing water to follow the bolt or screw threads down, and drip on the inside of your lockers. Two methods of solving caprail leaks. Remove the teak cap rail or aluminum extruded toerail and clean and re-bed each bolt. Radius the inside of the joint with epoxy and microballoons and then lay several layers of fiberglass tape over the inside of the joint, totally sealing it and strengthening the area at the same time. A more trouble-free hull to deck joint utilizes substantial fiberglass bonding on the interior of the joint, eliminating mechanical fasteners and leaks. (2) I say that leaks are caused by: (a) adding thru-deck fasteners improperly, (b) pushing the boat by the upper part of a stanchion instead of its base, and (c) etc.