ray lunder wrote:
Ahoy, I'm trying to figure out how to install this plastic holding
tank. So let's be optimistic and say the tank is half full and you
want to pump it all out and you're 3 miles out, etc. You open both sea
cocks, divert the Y valve to the holding tank and start pumping. But
doesn't this just fill the holding tank with sal****er as it flushes
out the waste? I want the tank to be clean and empty, right? Sorry if
this is dumb, I've never had a tank before. It's 6 gallons with two 1
1/2" stubs, one of which goes down to the bottom of the tank, and one
3/4" vent. Where does the vent get installed? All the stubs are on top
of the tank. Thank you.
The toilet is plumbed to the top fitting on the tank. The "stub" that
goes to the bottom of the tank goes to the input of the "Y" valve. One
outlet of the "Y" valve goes to the deck pumpout fitting, the other
outlet goes to a macerator pump then from the pump to the thru hull.
You need to install a vent thru hull somewhere in the upper area of the
hull. The macerator pump is used to pump out the tank when more than
three miles off shore. In the US, when inside three miles be sure the
"Y" valve is in the deck pump out position and locked else you risk a
citation if boarded by the coasties.
krj

ray lunder wrote:
On Mon, 03 Jul 2006 07:05:35 -0400, krj
wrote:


ray lunder wrote:

Ahoy, I'm trying to figure out how to install this plastic holding
tank. So let's be optimistic and say the tank is half full and you
want to pump it all out and you're 3 miles out, etc. You open both sea
cocks, divert the Y valve to the holding tank and start pumping. But
doesn't this just fill the holding tank with sal****er as it flushes
out the waste? I want the tank to be clean and empty, right? Sorry if
this is dumb, I've never had a tank before. It's 6 gallons with two 1
1/2" stubs, one of which goes down to the bottom of the tank, and one
3/4" vent. Where does the vent get installed? All the stubs are on top
of the tank. Thank you.

The toilet is plumbed to the top fitting on the tank. The "stub" that
goes to the bottom of the tank goes to the input of the "Y" valve. One
outlet of the "Y" valve goes to the deck pumpout fitting, the other
outlet goes to a macerator pump then from the pump to the thru hull.
You need to install a vent thru hull somewhere in the upper area of the
hull. The macerator pump is used to pump out the tank when more than
three miles off shore. In the US, when inside three miles be sure the
"Y" valve is in the deck pump out position and locked else you risk a
citation if boarded by the coasties.
krj


Thanks for your response. I don't have a big battery setup so I didn't
plan to have a macerator pump. Real pump-out facilities are few and
far between here. I just want to pump it into the sea after using the
holding tank in an anchorage for a few days. I though I would have a
switchable Y valve between the bowl and the tank; one position fills
the tank, the other pumps out the through the hull. Another non
switchable Y would be on top of the through hull catching both the
bowl and the tank before it exited.
p.s. what is ment by locking the Y valve? It actually has a place for
a padlock or something?

A macerator pump will empty a six gallon tank in about 30 seconds. At 14
amps thats about .1 amp hour. Surely your battery can handle that. If
not, there are manual pumps available. One made by Whale is about
$150.00. Most Y valves have a hole for a padlock.
krj

Take a look at my simple set up:

http://home.maine.rr.com/rlma/Strider0601.htm#Tee

(and continued on the following page)

No valves other than the discharge seacock. I used a 1" Bosworth pump
and it works great. The O-ring in the deck pump out is tight enough
for the pump to draw up into the Tee in the deck pump out line and I
haven't felt anything that makes me think the discharge needs to be
larger.

I didn't use a vented loop because the discharge seacock is normally
closed. Even if it was left over, back flow would have to go through
two pump oneway valves, fill the tank, backup into the head discharge,
overwhelm the joker valve, and then come up through the toilet. It
could happen over time but it's not a big enough risk to hand pump the
extra distance and possible odor through the siphon vent.

I removed the seacock handle and cable tied it to the discharge hose.
This is sufficient to show the USCG intent not use it inshore or
permit accidental discharge. I turn the seacock with vice grips when
I do use it three miles out.

--

Roger Long