Nigel Calder's "Boatowner's Mechanical and Electical Manual" has a good section on recommended head plumbing arrangements. Agree it sounds like joker valve is one of the problems but addition of a vented discharge loop would solve the unending supply of blackwater siphoning back through the joker. My head discharge has a non-vented loop that goes up to the underside of the deck near the rail then drops down (about 16") to a top holding tank inlet and has never caused a problem (even with rail buried for extended periods). Would have to have about 10 in. of the deck at the beam buried for it to be lower than water level. I did have siphoning from the intake and a vented loop under the lav cabinet (all the plumbing is there) about 6 " above the top of the bowl solved that so I never have to worry if someone leaves the flush valve/lever in the open or "fill" position. Have a Groco HF head with 13 gal tank above/behind the head.
Andy Weaver C&C 30 Mk I - '77 Wilmington, NC ---- Helen Abbott <[email protected]> wrote: > Gary: > It's been a long day, and maybe, the effects an adult beverage has > provided me with an induced state of brilliance, so after reading your > description of your on board 'plumbing system', to avoid unweIcomed > effluent backup in the head, I completely understand.....quite > brilliant really! > > Bob Abbott > AZURA > C&C 32 - 84 > Halifax.N.S. > > > On 2012/09/13 5:13 PM, Gary Russell wrote: > > There is another possibility to consider. In the case of my boat > > there were times when the level of the effluent in the tank was above > > the bowl in the tank. In my case the tank is transverse in the boat > > (head on the port side) and when on starboard tack the fitting on the > > port side of the tank is submerged and the effluent pressure goes back > > to the joker valve. The joker valves are never perfect and they will > > leak some. What I did is run a pipe through the tank from the head > > fitting in the tank to the opposite side of the tank, so the fitting > > is on the port side but the pickup is on the starboard side. Then > > when on starboard tack the effluent sloshes to port and the pickup is > > out of the effluent. When on port tack, the pickup is submerged, but > > is below the level of the head so it doesn't matter. That solved the > > problem for me. Does that description make any sense to anybody? > > > > Gary > > S/V Expresso > > '75 C&C 35 Mk II > > > > On Thu, Sep 13, 2012 at 11:25 AM, Wally Bryant <[email protected] > > <mailto:[email protected]>> wrote: > > > > Yup, it's not just salt, but an extraordinary amount of excess > > minerals are excreted through the kidneys (think about kidney > > stones,) and can build up in the hoses and the tank as well. For > > the last couple of years I have done an annual job of flushing a > > bunch of fresh water through the system, and then pouring about > > four gallons of cheap white vinegar down the head. I make sure > > some is in the bowl, and that the hoses are full of it. I let it > > sit for a day or two, then flush the whole system with fresh > > water. After that job I need to disassemble the pump and > > lubricate the O-rings with silicone grease. > > > > This particular problem sounds like a bad joker valve, though. > > > > Wal > > > > > > you wrote: > > > > Salt from urine crystallizes on your joker valve > > and the joker valve leaks back. Ideally we are supposed to > > flush clean > > water thru but it never happens on the Great Lakes when you > > are trying > > to conserve holding tank space. > > > > > > > > -- > > s/v Stella Blue > > www.wbryant.com <http://www.wbryant.com> > > > > > > _______________________________________________ > > This List is provided by the C&C Photo Album > > http://www.cncphotoalbum.com > > [email protected] <mailto:[email protected]> > > > > > > > > > > -- > > ~~~~~~~_/)~~~~~~ > > > > > > > > > > _______________________________________________ > > This List is provided by the C&C Photo Album > > http://www.cncphotoalbum.com > > [email protected] > _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com [email protected]
