Logic of how "compartments" drain in bilge of 3396

[palfvinverizon]

I've got water collecting in two of the "compartments" of the bilge under the salon in my 3396 and I'm trying to figure out the logic of the design.

There are six stringers running up from the back of the boat. The outer two on each side have rectangular cutouts (about 4" long by 2" high) near the hull that are apparently designed to allow water to run through. However, the middle two, surrounding the fuel tank, not only do not have cutouts. Given that there are also plywood "walls" between the stringers, once water gets into comparments on either side of the fuel tank, it can't get out. I've attached a picture of the aft starboard "wall" for this compartment.

As far as I can tell, all this structure is "factory" (if somewhat crude in appearance). I plan on dealing with the reason why water is getting in here in the first place, but I'd also like to enable water to drain out of here if it does get in. Before I start drilling holes in the base of these walls to enable that, I thought I'd ask if anyone understood what was going on with the design. Perhaps the plywood wall in the picture is NOT factory after all?

(Note: The plastic tank in the picture is a water tank add-on).

 

[pdecat]

Carver original bilge stuff is all painted gray.

 

[Audrey II]

I have a similar setup in my engine room under both motor the bilge has no drains when I asked why I was told to prevent accidental pump out of of oil or fuel through the bilge pump. I my case it worked because just before I took delivery of my boat I had the batteries changed while installing them they damaged the engine mount oil gauge no one noticed until my ride home. The gauge let loose and sprayed about 4 - 5 gallons on oil into the bilge beneath the motor I heard the alarm and shut down the motor with out damage. The nice thing is the closed bilge setup prevented pumping the oil overboard and make clean up much easier. I'm thing you have the same confinement setup.

I would not drill holes to interconnect although I did think about it also it's that way for a reason. But if you do, make sure you seal the exposed surface to avoid damage to the core.

What I decided to do is purchase a portable electric bilge pump with a long flexible hose now if and when I do get water in there I either pump it over board or into the main bilge area and let the bilge pumps pump it out.

 

[palfvinverizon]

Hmmm. That explains why they might not want fluid to flow between some compartments, but it still leaves me wondering about the basic design. Taking them one at a time:

* Plywood "walls" between the stringers - I'm guessing this is primarily for structural strength, although the walls are only 3/8" plywood. The "compartments are an outcome".

* Rectangular holes at bottom of two outside stringers around middle of boat - Is this really for drainage? If so, is it just to get the water more towards the center of the boat to keep it from tipping either forwards, backwards or sideways (even though it doesn't make it all the way to the center where it can drain?)

* Absence of drain holes in plywood walls - If the reason for the holes in the stringers is to enable water to flow and compartments isolate potentially toxic areas (e.g. under the engine), why not have a holes in the middle two stringers since the only fluid getting in there is going to be coming from outside of the outer stringer where there's no risk of oil, fuel, etc?

I wonder if anyone has drawn a "map" of the bottom of a 3396 showing stringers, walls, holes, etc.

 

[370 Motoryacht]

I highly doubt any of those plywood walls are a factory installation. Especially the one in the picture you posted.

 

[palfvinverizon]

Any other Carver Mariner (3396) owners want to chime in on whether they have these walls between the stringers in their boat? Mine is a 1977.

 

[imspacemancraig]

I have an '86 3297 Mariner. Any of the plywood "walls" throughout the hull area on the boat (including by the stringers) that were put in by Carver are painted gray in color, like the rest of the bottom of the hull. My guess is that the plywood you are seeing was put there by someone other than Carver at some point.

All the stringers that I have seen on my boat have those drainage holes that lead to one compartment or the other. Mine all seem to lead to the center compartment under the floor of the galley area first, then lead to the areas next to that. In fact, it took me a year to understand and figure this out with a lot of frustration.

I would constantly find water in the center area and couldn't figure out where it was coming from. It would only get to a certain level and never get any higher. Turns out that it was getting to a certain level before flowing into the compartment under the salon floor where the center bilge pump is located and and that would pump it out. I also finally discovered that the water was coming in from the back deck area in the engine compartment. If it rained hard enough that the the deck drain holes couldn't keep up, it would spill over into the engine compartment and make its way forward to the center area. Found this one fall after vacuuming the water out of the bilge prior to winterizing. It was bone dry and then I drained the water heater for winterizing (thinking it would stay in the engine area where I could vacuum it out there). I then went to the center area to get the pink stuff moving through the water system and found water back in the center area once again... low and behold, two plus two, figured out where the water was coming from.

 

[palfvinverizon]

Actually, the bilge is only painted gray in the engine area under the cockpit. The rest of the hull is unpainted. And the "walls" between the stringers are uniformly constructed/installed throughout. Unless another 3396 owner says that they do NOT have them, I have to go with them being "original".

 

[mariner36]

I have a 1985 Mariner36, so not the same as your boat. All Bilge compartment are painted grey, no plywood. I have seen the bilges on 5 other carvers ranging from 1984-1996, 30-40 foot, and all had the whole bilge painted grey, no ply wood.

Take it for what it is worth because I have never seen the bilges on your particular model.

 

[Unknown]

Gosh Peter, I'm going to have to side with the "non-factory" folks... I dont remember seeing anything like that in the bilge of any "6" series Carver I've ever seen...

In those days Carver did do some scary things though, perhaps you'll find another owner of that vintage with some ideas. On my 28s that definitely was not the norm in the bilge...