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43 Post - new owner question #1

Discussion in 'Post Yacht' started by Greg Page, May 14, 2021.

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  1. Greg Page

    Greg Page Member

    Joined:
    Mar 4, 2017
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    Location:
    Annapolis MD
    Trying to figure out/confirm the black water system thru-hulls. What I have figured out:

    The one under galley floor aft is the gravity tank drain (normally closed)
    The one under galley floor fwd is the head raw water intake since head doesn't flush if it is closed (normally open)

    The unknown:

    The one under the fwd stateroom floor has a second line Y'd to it with it's own valve. Is the Y'd one the head overboard discharge and the main one is ??? Are both closed when using the holding tank or just the Y'd one?

    What is the line T'd off the stbd engine water intake? It has it's own valve and connects to a PVC line going back under the cockpit floor.

    Thanks
  2. NYCAP123

    NYCAP123 Senior Member

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    You're mixing intakes and outflows in your questions. Let's go to your black water (what goes out of your toilet). You have a Y valve atop your holding tank. In one direction it sends it overboard, and in the other it goes to your holding tank. In most areas you must keep that turned to the tank side and cable tied in that position preventing overboard discharge. f you're out at sea and your holding tank is full you can switch it and discharge overboard or use your macerator to pump your tank overboard, but your dock neighbors won't be happy if you go overboard in local waters.
    With the intakes you really need to trace them to their end so you know what to shut off if you get a leak. I'm a little surprised to hear of PVC being used, but would guess that may have gone to or for a live well, possible your salt water wash down. And yes, anything in use needs to have the seacock open (motors, gen, saltwater head, A/C.
    Re: The Admin's post, nobody searches for 43' Post unless they're looking for general info on a 43' Post. They'll search for specific issues, i.e. holding tank, through hulls, black water, etc. So titling your posts that way will make them much more useful for people searching for answers in the future.
  3. boatpoor

    boatpoor Member

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    The PVC line teed off the engine intake may be a crash valve, I've seen PVC used in some Posts. What brand heads and pumps do you have?
  4. NYCAP123

    NYCAP123 Senior Member

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    Good thought with the crash valve, but I'd want the end visible. God forbid you use it and it runs dry.
  5. OutPost

    OutPost Member

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    Location:
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    One of my first projects was to abandon the raw water intake and switch over to a fresh water flush system. Cut my holding tank odor issues down to almost nil.

    The raw water seacock on my starboard engine is Td as well, on mine it feeds my AC units.
  6. NYCAP123

    NYCAP123 Senior Member

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    Switching to a freshwater toilet can be expensive, but IMHO well worth it. Easier to maintain and yes, gets rid of the stink.
  7. Greg Page

    Greg Page Member

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    Location:
    Annapolis MD
    Head is a GalleyMaid. I think the Y is at the thru hull based on similar picture in 42 post manual.
  8. Greg Page

    Greg Page Member

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    The Y at the thru hull is the diverter to the holding tank similar to the 42 Post manual.

    The line T'd to the stbd engine thru hull is a crash valve, pickup line runs to the stern behind the fuel tank in the bilge area near the aft bilge pump. Inlet is a section of perforated PVC and the end of the rigid PVC line.