Preventing water entering the black water vent

StodgeStodge Lake St. ClairPosts: 2,478Member ✭✭✭✭
I have a Big Orange filter for my holding tank.  Every time I go to change the charcoal in the filter there is a noticeable amount of water inside.  I don't think the wet charcoal is as effective as it would be when dry.

My guess is that rain water is running into the vent.  Since it's just a hole on the side of the boat there is nothing to prevent water entry.  Has anybody come up with a solution for this?

2002 FV 342 on Lake St. Clair - Past Commodore SHC - Vessel Examiner USCGAUX


  • skennellyskennelly ChicagoPosts: 1,384Member ✭✭✭
    Do you let your tank get full?  Meaning the liquids don't have anywhere to go but up the vent?
    2002 - 270FV Mag 350 B3
  • bella-vitabella-vita Buffalo NYPosts: 321Member ✭✭✭
    The vent hose should go up first than travel down so water can't get in
    2002 Rinker FV 342
  • Black_DiamondBlack_Diamond Holland, MichiganPosts: 4,613Member ✭✭✭✭✭
    I swapped out my thru hull vent with one meant for fuel and removed the internal screen meant for fire protection.

    Problem solved. 

    2003 342FV "Black Diamond", 350 MAG MPI, 20P 4x4 Props, PC BYC, Holland, MI
  • icoulthaicoultha Niskayuna NYPosts: 1,200Member ✭✭✭
    I wondered this too given I made my filter. But the fact it is pond/aquarium charcoal and gets wet I figure it's not a problem being wet. 



    The Third “B”

    Rear Commodore, Crescent Boat Club

  • skennellyskennelly ChicagoPosts: 1,384Member ✭✭✭
    The problem with it getting wet is it tends to clump together so not providing much surface area to absorb the nasty smells.  Activated carbon is all about surface area in order to get the most absorption.  In an aquarium you always want to have enough flow going through it to make sure it doesn't clump...same concept.
    2002 - 270FV Mag 350 B3
  • StodgeStodge Lake St. ClairPosts: 2,478Member ✭✭✭✭
    I don't let the tank get that full.

    The routing of the hose is different now that I've added the filter.

    I have looked at replacing the vent fitting.  Might be time to get that done.

    2002 FV 342 on Lake St. Clair - Past Commodore SHC - Vessel Examiner USCGAUX

  • raybo3raybo3 Revere MAPosts: 4,205Moderator mod
    Put a small piece of hose/tubing in it and let it stick out of the vent about a 1/2 inch. Problem solved. Actually should do that on all tru-hull drains and all the water stains will go away also....... Just say'n 
    2002 342 Fiesta Vee PC Point Of Pines YC Revere MA.
  • GMSLITHOGMSLITHO Greenwood Lake NY Posts: 735Member ✭✭✭
    It’s probably condensation from the tank venting and whatever water drips down from the outside 
  • mattiemattie Sarnia, OntarioPosts: 249Member ✭✭✭
    edited May 14
    I ordered a SeaDog stainless 90* gas tank vent. Fits a 5|8” vent hose hook up. Really nice unit with 2 downward facing vents.
    Post edited by mattie on
    246BR, 276BR, H310BR current
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