This might be an unsolvable question, but figured I would try you guys here just in case your collective genius can find something that I'm missing.
The floorboards underneath one of the heads in my 1986 Nova Sundeck continuously seem to be getting wet. Not a lot, but definitely damp. This is either caused by, or is the cause of, water damage to the veneer along a couple of walls directly outside of the head. I've attached pictures of the floorboards under the head [picture 1], and the water damage to the walls [picture 2].
Complicating things is that our water heater exploded about a year ago, flooding this area and probably causing some of the damage to the walls that you can see in Picture 2. I was gone at the time though and my girlfriend swears that the damage that is there now is unrelated to the water heater (she's usually right about such things).
My initial thought was that one of the pipes leading into or out of the head was leaking and causing the water damage, which seemed to be logical given that there was a bit of wetness coming out of the raw water inlet line when we flushed the electric motor. I removed the head completely and blocked off that pipe while I dried out the floors. At this point I noticed that we also had other issues, including a macerator which had broken in half and a leaking vented loop coming from the bilge pump underneath the holding tank. This meant that the holding tank wasn't holding anything, and all waste products (we use our heads for #1 only) were being pumped directly out by the bilge pump with some leaking out through the leaky vented loop which was underneath the sink in the head. I figured this too could have been a source of the wetness and water damage.
The head has been off for almost a week now and the vented loop and holding tank were all fixed, and everything was dried thoroughly. However, the moisture still seems to be coming back. (note: walls do seem to have stayed dry, although its hard to tell for sure).
So here are my guesses:
1. The pipes for the raw water inlet could be 'sweating', causing the moisture that is still coming back there. They're old hoses, so I guess this could be possible. You can see in picture three, it is the hose on the right hand side of the picture leading into the vented loop. Possibly supporting this theory is that the two small holes where the raw water line comes in appear to be damp, whereas the other holes (the one above and the one to the bilge) do not.
2. There is water somehow making its way to this cavity either from a leaky window, or from some other area that I can't find. There is a window nearby that has leaked in the past [see picture 4], but the water would have to travel along the inside of the hull behind the walls and pool underneath the head. I haven't found evidence for this in any other area, but its hard to get any visibility back there.
3. I'm crazy and there is no moisture, or the moisture that is there on the floor boards is just residual or caused by humidity or evaporation from the bilge, and all previous water damage to the veneer was caused by the slowly leaking raw water line when it was hooked up, as well as the previous damage from the water heater.
Sorry if this was too long of a narrative, but clearer perspectives would be very much appreciated. I've been staring at this issue for too long and now its starting to seem like the boat is conspiring against me.