Does the bilge go under the gas tank to the front compartments? Is there any foam around the gas tank? I had an oil line start seaping a few weeks ago which was no big deal. Just wiped it up with a rag. Ordered cooler lines and went out the next weekend. Well, we stayed out and got a huge thunder storm that night. Must have gotten 10 gallons of water mixed with that 1 cup of oil in the bilge.
Anyway, up in the foward compartments I got some oil residue from driving the boat that Sunday and the water/oil mix sloshing around. It kinda smells up the cabin.
Can I just get some cleaner and pour it in the drain holes in these compartments then run the garden hose down through there?

On mine there is a drain that runs under the tank from the cabin to the bilge. also there is a compartment up under the v berth that is also tied to the same drain route. Mine had carpet and it smelled so I pulled it out.

In my 253 if I get even a little water in the bilge it will slosh up into the cabin floor so I put an expansion type drain plug in there and solved that problem.