I have an old Clark Rubber inflatable dingey that has a small or number of small holes in it that are nigh on undetectable. I've done the soapy water thing but 48hrs later the thing is soft. I am trying to find a seler that you pour into the chambers, blow it up and swirl it around to seal from the inside. I have contacted a company in the US but bet they won't ship, Clarke rubber has nothing, Whitworth Marine has nothing, ebay has nothing - any ideas? Its a good strong rubberised canvas boat and worth the effort.