On my current
boat, (Beneteau) , the holding tank
is above the water
line, so simply opening the seacock empties the tank. What I like about this simple gravity fed system is there is no pumping, no pump to fail and the through-hull is closed most of the time. Everying goes into the holding tank
and it's easy to empty where appropriate, with little danger
of discharge when people are swimming due to leaving a y-valve in the overboard
position. I've chartered several other boats with the same system and never enountered any problems. One thing I've noticed however, is the exit plumbing
is a larger diameter than the typical 1 1/2 inch discharge on most boats. It looks like about a 2 inch diameter to me.
Now my question: A new boat I'm purchasing
needs a plumbing
upgrade and since the holding tank is also above waterline, I've though of converting it to the above mentioned system. The current
and seacock (which need replacing) are the standard 1 1/2. My question is while this is what is typical for most marine head
systems where the sewage is pumped out, would this diameter likely cause issues with a gravity fed system? (having less pressure) My guess is there is a reason the Beneteaus go with a larger diameter, but I've never seen plumbing hardware
larger than 1 1/2 carried anywhere.
Has anyone ever seen this system with stanard 1 1/2 plumbing and if so how well did it work?
Any thoughts on where to obatain marine
plumibing fixtues of a larger diameter?