Originally Posted by RDW
I realize that I was not clear on what kind of leak. It is a leak of water into the dinghy not air leaking out.
Yeah, that's what I thought when I first saw the title of the post. Double Hull right? If so, they all (or nearly so) leak between the hulls. I've dealt with loads of them in the charter
fleet in Belize
and eventually they all have developed this problem. See other threads here on CF on this subject.
On mine, I drilled holes in the floor next to the hull/deck seam running fore and aft every few inches and used a short section of small hose to shoot foam up into the seam area. This has worked out pretty well. It did not entirely stop the leak, but slowed it down dramatically.
I've also thought about cutting out part of the transom between the hulls and installing a large scupper with one-way flapper and just let the hulls leak -- water should drain as the boat comes up on plane.