Scupper design question

Discussion in 'Boat Design' started by Busman1965, Jun 11, 2021.

  1. Busman1965
    Joined: Jun 2007
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    Busman1965 Junior Member

    Im helping a friend with a problem boat he just bought and need some technical advice. The boat is brand new, and was rigged at the factory exactly as it sits. His boat is a fairly standard big (36ft) center console boat with 3 350hp outboards on it. The boat sits at rest with the cockpit scuppers half submerged even when not full of fuel and water. The cockpit deck is below the scuppers, so it is right at, or just below the waterline.

    The scuppers are the large oval type with the rigid one way flap on a hinge. The issue I have is they are located right over a virtually unsealed compartment (a fish cooler on each side of the cockpit, at the stern with a simple hatch and a cheap foam spaghetti seal). These fish boxes are not self bailing and do not have automatic pumps in them.

    The raised lip around the opening of these boxes usually has seawater from the scuppers about half way up the lip, which means only about 1/2" to 3/4" of protection before the water intrudes in the non draining fishboxes. The manufacturer says that the have sold lots of boats this way and it is fine.....I do not believe that it is safe or in anyway good engineering.

    My big question is isn't there some regulations on drains, that are even partially submerged, being required to have seacocks? In this case because the deck is obviously not water tight at the hatches beneath the scuppers, it is a huge safety issue, I feel.

    Is anyone savvy enough on regulations in the USA (USCG, ABYC etc.) to give me a direction to look? Most of my background is small hydrofoil sailboats and commercial boats, so this big center console is not in my area of expertise. This boat has attempted to sink 2 times dockside, just from small waves rocking the boat, and water splashing over the lip of the fish box for a period of time,thus filling them and increasing the rate water gets in.
     
    Last edited: Jun 12, 2021
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    No good, the obvious course might be to modify those fishboxes such that water can't drain in to them.
     
  3. Busman1965
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    Busman1965 Junior Member

    I agree, but being a new boat, I want the manufacturer to acknowledge the design flaw and repair it for this fellow, which they have not done so far.
     
  4. bajansailor
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    bajansailor Marine Surveyor

    I guess that you are probably hesitant to identify the make of boat, or even post a photo or two - but I think that your concerns mentioned above are very valid, and that you have simply reported facts, hence I don't see how this post could be contentious or possibly libelous.

    But it would help if you could provide some more info re the boat, and / or some photos showing what is happening.
     
  5. kapnD
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    kapnD Senior Member

    Sounds like it may have too much weight hanging off the transom. It would be a good idea to verify that the triple engine installation was approved by manufacturer.
     
  6. bajansailor
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    bajansailor Marine Surveyor

    This amount of power seems to be fairly standard for boats of this size now - taking a typical example, the 35' Boston Whaler centre console has a maximum power limit of 1,200 hp and a minimum requirement of 750 hp -
    350 Outrage https://www.bostonwhaler.com/boat-models/outrage/350-outrage.html
     
  7. Mr Efficiency
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    Mr Efficiency Senior Member

    It isn't that unusual to find self-draining cockpits that are too low, when boats are loaded right up, but this one seems a little too low, maybe as a stop-gap measure, replace the hatch spaghetti seal with a slightly thicker one, if the existing one leaks.
     
  8. Busman1965
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    Busman1965 Junior Member

    Thanks for the replies! As to the weight for the engines, I believe it is too much also. It was rigged by the builder at the factory this way and they even offer bigger motors than these 350hp triple outboards. I will try and get some photos to post that do not give away the manufacturer.

    If this boat had actual waterproof hatches it would not be a big issue(it would just be a wet deck boat, but a long slim pair of hatches on each side of the cockpit, all the way to the stern means that the scuppers will fill the fish boxes on both sides, as has happened 2 times now. I will see about some temporary foam to seal them with, but I don't want to pull the factory stuff off, as it may become needed, if there is a lawsuit.

    My main reason for getting involved in this stems from my having spoken to the manufacturer 2 times, and both times I have been brushed off, their defense has been "its fine, we have built xxx number of these". Just because they made a number of unsound boats, does not mean it is correct.

    I recall something in regulations or recommendations by either the USCG or ABYC that require seacocks on even partially submerged drains or freeing ports? I know in my commercial boat days, no inspector would pass open flapper type ports in the cockpit that were anywhere near the waterline of an unloaded boat.

    If anyone knows the details of these rules/specs regarding this type of scupper setup, it would really help me to go the manufacturer better equipped with information....
     
  9. Busman1965
    Joined: Jun 2007
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    Location: Florida/Bahamas

    Busman1965 Junior Member

  10. Busman1965
    Joined: Jun 2007
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    Busman1965 Junior Member

    These are photos of the most recent partial sinking. If you look in the first one,you can see the water running over the lip of the hatch coaming. The little basin between the scupper and the hatch coaming is always partially full of seawater, as it is below the waterline. Basically the little bit of hatch coaming is all that keeps this boat afloat, as there is no way that hatch could be considered waterproof. This is what I would consider a waterproof hatch for that sort of deck arrangement.
    index.jpg index.jpg
     
  11. Mr Efficiency
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    Mr Efficiency Senior Member

    Seal seems faulty, you might investigate a better replacement, refrigeration people might advise on that, but unless everything is rigid with the hatch and the mating surface, a good seal is difficult, or would require a thicker seal.
     
  12. Mr Efficiency
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    Mr Efficiency Senior Member

    You don't need much of a warp in the hatch or where it seals, to make a slender seal ineffective.
     
  13. Busman1965
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    Busman1965 Junior Member

    Yes agreed, its not terribly rigid or straight, so getting a waterproof seal is not going to be easy. I know I could solve the problem with a tube of 5200 (glue them closed or put in bilge pumps in the fish boxes), but I'm trying to get the manufacture to fix the design issue in this case. The is a brand new boat,and was hugely expensive for its length, high 6 figures kind of money, and I believe they should be held accountable for a shoddy/unsafe design... The owner is not well versed in boats, so I wanted to help him out, as I have been in the marine industry my whole life, and know a good bit about boat design in general.
     

  14. Mr Efficiency
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    Mr Efficiency Senior Member

    I certainly wouldn't be happy to leave it like that, but you do see some "funny" things in quite expensive, well known brand boats.
     
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