Welcome Guest - Sign Up today
Welcome Guest - Sign Up today

Announcement

Collapse
No announcement yet.

Fuel tank install with water under to bilge

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Fuel tank install with water under to bilge

    Hey general population. I see a lot of guys putting fuel cells/tanks and letting water run under them back to the bilge.
    To me a gas tank is supposed to be placed into a "coffin" as a sealed unit. Not using the hull as a base structure to support the tank.
    I know it's your boat and you can do what you want.
    How do all you rehabbers feel about this and what's your opinions.
    I am interested in this and would like to see the overall population make comments.
    Most times I'm wrong, Most times I stand corrected..But...Sometimes I'm right.
    1983 SportCraft Deep V OSFF 222 Cuddy Rehab
    https://forums.iboats.com/forum/boat-...ddy-walkaround
    https://forums.iboats.com/forum/engin...-new-fuel-pump
    www.flotationfoamsolutions.com

  • #2
    My boat was built to allow water to run under the fuel tank (from the ski locker) and out the back into the bilge. I kept it that way when I restored it.
    Location: West Central Illinois, USA 1997 Larson 186 SEi Bowrider I/O Mercruiser 350 #0F747565 Mag Alpha One Gen II #1A270120 Transom and Deck Restoration Project on my '97 Larson Bowrider

    Comment


    • #3
      The coffin is meant to contain fuel from a ruptured tank or hose so you and the passengers don't spend eternity in one.
      BOAT SPECS FORUM HELP STARCRAFT FORUM SHOP iboats
      Please, no PM's (Private Messages) regarding boat/engine problems.
      That is what the forums are for.
      Only forum/moderator issues will be answered in PM's.

      Comment


      • #4
        Way mine was built as well. I was concerned when you mentioned it. But if it was sealed no drainage from the skii locker if changed. And I looked hard nobody ever changed it in any rebuild I ever saw.

        Sealed areas with vapors are the real grenades. All the gas in the tank is being pumped to the bilge anyway. There is a dozens of places it could leak from in there. I googled it and found zero problems with tanks being that way. Fuel pumps filters and hoses. Fuels systems both carb and fuel injection now there are your fire and explosion culprits 99.9% of the time.

        After massive reading I kinda came to the conclusion. In a small boat with no cabin. Open air there is little danger. Hard to build up vapors in a bucket in the middle of a open field. Have you ever tried to light gas not happening in the liquid state. With no sealed room it is removed by a simple breeze. If your tank is leaking bad enough to be a issue it gonna smell like gas.

        Problem is when the tank and engine compartment are sealed under the deck. Now there is a large area that gas vapors can fill and that is alot of boom. In a space sealed so you don't smell it and have no warning. In a larger boat like that the coffin system seals the area the vapors can gather to a small as a area as possible.

        I based my decision to leave the way it is on 2 things.

        1. There are now and never were reports of boats going boom from gas tanks being in this configuration.

        2. Gov agencies are nasty unthinking unfeeling people. Love to push people around over the simplest stupid things. If there was any issue at all they would not let boat manufacturers build them that way to this day. I am sure they have tested and exploded boats on purpose trying to make a problem that don't exist.
        Dance with the waves,
        move with the sea.
        Let the rhythm of the water
        set your soul free.

        1987 Four Winns 170 Horizon.

        Comment


        • #5
          The fuel tank bays on both my recent boats we not fully sealed coffins. They were open at the top. Leaking fuel could not readily get into the bilge because of solid bulkheads both front and back of the tank. But any fumes from the tank could/would vent to other areas of the boat.

          Water from the forward section of the boat was/is channeled under the fuel thank by via a sealed conduit/hose.

          The tank essentially rested on the hull although supported by neoprene strips.

          So, not a fully sealed ‘coffin’ is not typical on all boats, but common on smaller boats with belly tanks.
          Best regards, Ted . . . . Cape Cod, MA

          Current Boats: Formula 330 Sun Sport, O'Day Mariner Sail #3224, Sunfish
          Past Boats: Catalina 22 Sail #10531, Formula 242 Sun Sport
          Twin Mercruiser 7.4 LX MPI (0F802036, 039), Bravo 3's (0F806198, 199), Mercury 7.5 HP (1969), Johnson 4.5 HP (1980)

          My Boating Web Pages: http://www.tpenfield.com

          Comment


          • #6
            I've never heard of a 'coffin' fuel tank enclosure. It sounds like an industrial tank farm enclosure. I'm thinking once a fuel tank leaks, fumes are the greatest hazard. It would seem fuel in the bilge would be the earliest method of detection vs. having the stuff accumulate hidden under the floor. The few boat gas tanks I've seen are set somewhere on the hull, with a drain channel if located on center. I go for belt and suspenders in some instances. This one doesn't make sense to me.
            '96 Larson 174 SEI BR. 4.3LX 4 bbl Weber s/n 0F786604. Alpha One Gen II s/n 0F709315

            Comment


            • #7
              Fwiw my project was originally manufactured in Canada (Campion) and the tank was built all the way in the rear of the boat so the tanks level gauge, inlet, and breather tubes all have open access near the bilge. If I was to put it back in it's stock location and seal it, it would prevent everything from the bow towards the tank from being able to reach the bilge.
              Last edited by steve_h7; February 7th, 2019, 04:36 PM.

              Comment


              • #8
                Thanks guys for the feedback. I appreciate it. This is one of the mysteries to me and coast guard regs. I will be placing a sniffer alarm in my coffin in any event.
                Most times I'm wrong, Most times I stand corrected..But...Sometimes I'm right.
                1983 SportCraft Deep V OSFF 222 Cuddy Rehab
                https://forums.iboats.com/forum/boat-...ddy-walkaround
                https://forums.iboats.com/forum/engin...-new-fuel-pump
                www.flotationfoamsolutions.com

                Comment


                • #9
                  here is issue i see with coffin idea , by the time you know there is a leak the leaked fuel is all over inside and can possibly soak into stringers and making vapor where as if it leaks into bilge you immediately know there is a issue and can resolve it.
                  project:https://forums.iboats.com/forum/boat-...r-2159-hardtop
                  Previous project https://forums.iboats.com/forum/boat...rint-bass-boat
                  Previous previous project/conversion https://forums.iboats.com/forum/boat...rsion-splashed

                  Comment


                  • #10
                    I have no issue with the coffin, I feel safer. A sniffer will let me know whats up Doc before all that happens. The fuel to the battery compartment would be my scare.
                    I have also seen guys put a valve off the box for check ups now and then, That seems plausible.
                    Most times I'm wrong, Most times I stand corrected..But...Sometimes I'm right.
                    1983 SportCraft Deep V OSFF 222 Cuddy Rehab
                    https://forums.iboats.com/forum/boat-...ddy-walkaround
                    https://forums.iboats.com/forum/engin...-new-fuel-pump
                    www.flotationfoamsolutions.com

                    Comment


                    • #11
                      To me a gas tank is supposed to be placed into a "coffin" as a sealed unit.
                      Ayuh,..... I disagree, as in my experiences, Any sealed compartment in a boat, is a water-trap,.......

                      My thought is, Any, 'n Every compartment should be self-draining to the bilge,......

                      Comment


                      • #12
                        Originally posted by Bondo View Post

                        Ayuh,..... I disagree, as in my experiences, Any sealed compartment in a boat, is a water-trap,.......

                        My thought is, Any, 'n Every compartment should be self-draining to the bilge,......
                        I agree to disagree! Good hearing from ya Bondo
                        Most times I'm wrong, Most times I stand corrected..But...Sometimes I'm right.
                        1983 SportCraft Deep V OSFF 222 Cuddy Rehab
                        https://forums.iboats.com/forum/boat-...ddy-walkaround
                        https://forums.iboats.com/forum/engin...-new-fuel-pump
                        www.flotationfoamsolutions.com

                        Comment


                        • #13
                          Originally posted by Bondo View Post

                          Ayuh,..... I disagree, as in my experiences, Any sealed compartment in a boat, is a water-trap,.......

                          My thought is, Any, 'n Every compartment should be self-draining to the bilge,......
                          Yup, 30 years later any my substructure was mostly solid wood with that exact setup
                          "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

                          Current Boats
                          10' tin gamefisher/Johnson 7.5hp ob
                          1991 Sea Ray 170br/AlphaMerc
                          1996 Century 1800 CC/Yamaha c85
                          1988 Imperial 280SF (under the knife)
                          1972 Checkmate mx-15

                          https://forums.iboats.com/boat-restor...cs-598307.html

                          Comment


                          • #14
                            All compartments self draining to the bilge hmmmm I like that idea too!

                            If only there was a way to do that with 2 part foam...hmmmmm.
                            Last edited by kcassells; February 8th, 2019, 05:50 AM.
                            Most times I'm wrong, Most times I stand corrected..But...Sometimes I'm right.
                            1983 SportCraft Deep V OSFF 222 Cuddy Rehab
                            https://forums.iboats.com/forum/boat-...ddy-walkaround
                            https://forums.iboats.com/forum/engin...-new-fuel-pump
                            www.flotationfoamsolutions.com

                            Comment


                            • #15
                              Sign up today
                              I am so happy My boat has no foam
                              project:https://forums.iboats.com/forum/boat-...r-2159-hardtop
                              Previous project https://forums.iboats.com/forum/boat...rint-bass-boat
                              Previous previous project/conversion https://forums.iboats.com/forum/boat...rsion-splashed

                              Comment

                              Working...
                              X