|In the past, I have found the cockpit locker lids to be a source of rainwater leakage. The water travels around the back edge of the lid and across the underside of the lid, bypassing the teak coaming around the opening of the locker. Somewhere around the middle of the lid, it comes to a stop and drips down into the lockers, eventually ending up in the bilge. I greatly reduced this problem by using caulking to create a small ridge along the back edge of the locker lid. Once the water flows over the back edge of the lid, it flows down this ridge and then would need to flow uphill to make it back onto the underside of the lid. This works well for rainwater, but not when we ship it green over the cockpit coaming.
If the toerail is leaking, this need not be a major issue. At one point Carriden developed a toerail leak after being bumped on the racecourse. Tightening up the toerail bolts slightly recompressed the butyl caulking and eliminated the leak. That is the joy of butyl caulking, which remains pliable forever, and why I continue to swear by it. Nothing that I have bedded in butyl has ever leaked. Every other space-age caulking that I have tried has failed me. I am also progressively replacing all of my toerail bolts with nylock nuts, which do not work loose.
Another potential source of leaks is the chainplates for the shrouds. Have you checked them? Look for streaking on the bulkheads below the plates. A dozen years ago, I pulled my chainplates, removed the balsa core around the openings and replaced it with epoxy. I then replaced the chainplates, adding some stainless steel backing plates, and spent 20 minutes per chainplate packing the opening with butyl caulking. They have been bone dry ever since and there has been no water penetration into the deck either.
You can use baby powder or talcum to reveal the path of leaks. Just put a light, even dusting of powder onto the suspect area. If any water travels across the area, its path will be revealed. Never use flour or cornstarch, or other food-type material, as the leftover powder may drift into hidden areas, feeding mould and even bugs.
Hope that this helps.
Marcus from Carriden
Mk III, Hull #847