Doing it on our '77 h27
And Steve is right, it is expensive. That's because you have to cover all surfaces that communicate with the air in the cabin or cockpit. You also have to be meticulous, because _any_ air leak will transmit the sound at full volume! That means you have to figure out how to get air into the engine. The two suggested approaches are a fan, or a passage with baffles. I am using the latter technique at the aft end of the engine compartment under the cockpit, where there is an air path leading to the stern area, and a couple of vents on the aft coaming. I did get good advice in a thread about a month ago, so you could try the archives to see the advice on suppliers. I and using the West Marine material in one inch thickness, and using two layers for most of the work. The lower walls of the compartment are part of a structural "bench" forming the floor of the cockpit locker on the starboard side, and the bottom of the aft bunk to port. Since both of these cavities look sealed, I don't think they will transmit sound very well. I won't be able to test the installation until we relaunch on the spring, but I will report then. David Lady Lillie
