Deck drain issue

[CascoBay]

I have a 2000 Larson 254 Cabrio with a molded in step that goes down to the cuddy.

The problem I have always had was that the drain never worked correctly, there was always water in it- here's why:

Now I went out and cut the rise out of the hose:

However I am now realizing that the rise was there to avoid any raw water from going backward into the step area when the boat rocks and rolls.

Bottom line is, I need this resolved!

Here is another photo which will lead me to my next idea:

I am thinking of installing a small watertight box (Sump) below the step and direct the water into it, install a small 360 gph bilge pump with float and check valve to pump the water out of the original 1.5" thru hull (will have to bush this down to 1/2" or so).

The other idea I had was to install a straight fitting in the step and direct the hose under the rear cabin and into the rear bilge area to let the pumps back there deal with it as needed. The issue I have is dirt, and trash perhaps would migrate back to the rear bilge and clog pumps and make a mess- here is a shot of fuel tank which is under the cabin floor, I can easily run a hose on top of the tank.

The last idea I had was to direct the water to the forward bilge (as seen in anove photo). This already has a pump, I just worry about the debris issue again and the fact that it is a really small area. My thought is that I want to keep the bilge as dry as possible, this would not acomplish that.

Any thoughts would be great, thanks!

 

[Bondo]

Re: Deck drain issue

However I am now realizing that the rise was there to avoid any raw water from going backward into the step area when the boat rocks and rolls.

Raw Water,..?? From Where,..?? What's beyond the bulkhead,..??

 

[CascoBay]

Re: Deck drain issue

The bottom thru-hull is the one in question.

 

[bobdec]

Re: Deck drain issue

Are you the only one with a design fault !!! It seems the step drain is actually below your water line during wave and other action so the only way is to pump the water out. I would do your last idea, just run a hose to the rear bilge pumps and let them handle the problem. I assume the step drain only takes water during rain, swimming activity, and heavy seas splashing into the cockpit area while under way. So it wont be a constant drain problem on the main pump(s). If worried about debris entering the main pump(s) install a small fiberglass piece of screen or drain filter in the drain opening that you can l visibly inspect, and easily pull to clean it out. However if you are overly concerned to have an absolute dry bilge then adding a collection box (or bucket) with a pump to a exit point above the water line would be an alternative. I would not use the existing fitting that is below the water line for the pump, plug the hose and use double clamps or glass over the opening.

 

[CascoBay]

Re: Deck drain issue

Thank you for the input. I just made a material list to do the sump box, too much time, effort, and money doing it that way.

I think you are right in letting the rear bilge pumps to do the job, and I like the screen idea at the deck drain.

The thru hull fitting is above the water line:

Perfect fitting:

 

[makinhole]

Re: Deck drain issue

How about an inline check valve allowing the drain to freely flow out, but checking any incoming water?

 

[CascoBay]

Re: Deck drain issue

I am concerned it may not operate correctly give the downhill angle and the lack of any head pressure?

 

[26aftcab454]

Re: Deck drain issue

I would go with the fairly level drain hose- I have a similar drain in the head/shower drain- thru hull is 2 inches higher and the floor is only a couple inches above that- I have never seen any water come in. And if it did it would drain right back out .

 

[Fisherball]

Re: Deck drain issue

You could put the hose back as original except have the top of the trap below the level of the drain inlet. Make it about half way between the levels shown in your b/4 & after pix. Put the trap closer to the thru-hull fitting so there is more height without being above inlet. It would be real tight but it appears there is enough room. Than you would not have to rely on a pump & your bilge will stay dry.

 

[shrew]

Re: Deck drain issue

Personally, I would not drain water into the bilge if I could avoid it. What should be 'self bailing' now relies on a 12v electrical connection and powersupply. If the battery dies, if you loose shore power, if the pump dies, fuse blows, you will be essentially flooding your boat. The shower sump is a bit different because the water can be turned off and even it it weren't the water tank would eventually run empty. You can't control water from outside like rain the same way.

I can't offer a solution, but I would not be going down that particular path.

 

[sasto]

Re: Deck drain issue

If she were mine...I would certainally install a shower sump with a good pump and float switch. Been done for years.

 

[CascoBay]

Re: Deck drain issue

Thanks for all the input. The check valve seems like the best idea for simplicity- any idea how one would work on this slope/application?

 

[CascoBay]

Re: Deck drain issue

I think I found the ideal product:

TH Marine Scupper Valve, even takes a 1.5" hose- perfect.

 

[CascoBay]

Re: Deck drain issue

Problem solved- check valve installed, 90 degree step fitting has been re-bedded, and a support clamp installed.