2012-12-29 — The Tale Of Black-Water Jack (Part I)

I keep hearing you are never quite become “one with your boat” until until you wade (figuratively speaking) into your Black-Water System.

Most boats have a potable water (drinking), grey waste water (sink drains) and of course black-water. You can guess source of the later I am sure! The laws for sewage disposal are pretty straight forward. When inland/shore water disposal is in a tank and when you get into port you use a big vacuum device to empty said tank. When you are in the ocean though (3 miles or more off shore) you discharge directly to the ocean or you can empty your tank into the ocean.  The later part of the statement is where we meet Magnolia. She has a tank of course and the ability be vacuumed at the dock but was not equipped to empty her tank at sea. This becomes a particularly important capability in the Bahamas since they don’t have pump facilities. (I understand “some” marinas are being equipped.) The only way to dispose of black-water there is off shore in the ocean. This calls for Magnolia’s current system to modified with the addition of 2 valves and a pump to empty the tank. This project will add a “Overboard Selector Valve” and a “Tank Discharge Selector Valve” along with the “Pump” which will be a Whale brand Manual Sanitation Pump designed exactly for this purpose.


First is to remove the 1 1/2”  “Tank” and “Overboard” hoses from existing valve.


Select the location for the “Overboard” selector valve.


I used West System two part epoxy to attach mounting block to the hull interior. The manual described the consistency to be like peanut butter. Obviously my first batch was a little on the runny side of peanut butter.  I got it right the second time though!


After a little clean up, a count of primer and coat of paint nearly ready to go here. Well except for a last minute decision to replace the hose connected to the deck fitting, so one more to pull out then we really are ready to go.


The pump and “tank discharge selector valve” will be mounted on the stringer just aft of the rudder post so we will need to add an access hatch there. (Note: I don’t recall if Grandpa Emerson or Dad gave me that jig-saw but I suspect its as old as I am and twice tough!)


I also took the opportunity to give the tank/bladder locker a coat of 2-part epoxy to make sure things were really sealed up in case of leaks!


With all the old hoses removed and compartments freshly painted next we will start putting it all back together next weekend!

1 thought on “2012-12-29 — The Tale Of Black-Water Jack (Part I)

  1. Anthony, I’m so glad you left the link to your blog. I’d been to your website a few times but never found a blog there. So now I’ve finally found it and added it to my blog aggregater.

    And I really really feel your pain on the black water system. Hope you flushed out with water and maybe some bleach a few times before you start playing with it.

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