Any suggesstions?
Some of the better hotels use some kind of high-tech product to get the
stank out of a room.
Ozium is one of them, and there are probably more. They don't just cover up
the smell: http://www.atmosphereproducts.com/pr...ium/index.html

Here's more suggestions:
1. run the boat at speed with all ventilators open to get some of the
surface odor to float off.
2. Get an ozone generator and leave it running inside the closed up boat.
I think ozone can degrade some odors. Some air purifiers have electrostatic
scrubbers that will attract odor particles as well as releasing ions that
can act on odors that are still attached to items.
3. If whatever caused the odor is still causing the odor, then you have to
find the source.