Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve,
and through hull. The easiest way to mount the macerator pump is to
screw it into the outlet of the tank then plumb to the y-valve. Question
is, will the pump out be able to suck through the pump or can I turn the
pump on while pumping out the tank. Also is there any problem with
pushing stuff through the Y-valve rather than pulling through the valve.
Thanks
krj

On Feb 2, 5:06 pm, krj wrote:
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve,
and through hull. The easiest way to mount the macerator pump is to
screw it into the outlet of the tank then plumb to the y-valve. Question
is, will the pump out be able to suck through the pump or can I turn the
pump on while pumping out the tank. Also is there any problem with
pushing stuff through the Y-valve rather than pulling through the valve.
Thanks
krj

Typically the Y-valve diverts the contents of the head either to the
holding tank or overboard through a thru-hull fitting. You could cut
into the holding tank pumpout hose and install a T and run your
macerator pump off that. That way the pumpout process wouldn't be
sucking waste through the macerator pump. The discharge line on your
macerator pump would then go to your thru-hull fitting thru a looped
hose with a syphon break fitting. The Y valve wouldn't be involved at
all in evacuating the holding tank.

wrote in news:1170471858.010168.132370
@a34g2000cwb.googlegroups.com:

On Feb 2, 5:06 pm, krj wrote:
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve,
and through hull. The easiest way to mount the macerator pump is to
screw it into the outlet of the tank then plumb to the y-valve.
Question
is, will the pump out be able to suck through the pump or can I turn
the
pump on while pumping out the tank. Also is there any problem with
pushing stuff through the Y-valve rather than pulling through the
valve.
Thanks
krj

Typically the Y-valve diverts the contents of the head either to the
holding tank or overboard through a thru-hull fitting. You could cut
into the holding tank pumpout hose and install a T and run your
macerator pump off that. That way the pumpout process wouldn't be
sucking waste through the macerator pump. The discharge line on your
macerator pump would then go to your thru-hull fitting thru a looped
hose with a syphon break fitting. The Y valve wouldn't be involved at
all in evacuating the holding tank.




Isn't the Y-valve REQUIRED by the regs to be installed? The common port
on the Y-valve goes to the tank bottom outlet, one port goes to the
pumpout fitting on deck for the vacuum hose to mate with. The other port
on the Y-valve goes to the mascerator pump and out to the ball valved
thru-hull fitting to sea. You're supposed to lock the Y-valve in the
pumpout position while you're in the harbor.



Larry
--
Democracy is when two wolves and a sheep vote on who's for dinner.
Liberty is when the sheep has his own gun.

"krj" wrote in message
...
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve, and
through hull. The easiest way to mount the macerator pump is to screw it
into the outlet of the tank then plumb to the y-valve. Question is, will
the pump out be able to suck through the pump or can I turn the pump on
while pumping out the tank. Also is there any problem with pushing stuff
through the Y-valve rather than pulling through the valve.
Thanks
krj

I've had very good luck with this very simple set up shown on this and the
following page.

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

No "Y" valve, no macerator pump. You have to pump by hand but, hey, we
could all use a little exercise at our age.

There is no direct overboard discharge I find pumping out the tank
occasionally less trouble than remembering to constantly switch back and
forth as we move in and out of no-discharge zones. In our home waters, we
usually have to make a special diversion to get to an area where we can
pump. Most pumping is dond at the dock.

The deck fitting seals well enough that the hand pump sucks through the "T".
When back flushing the tank with fresh water, I open the discharge pump the
hand pump a few strokes as the FW runs to clear the discharge lines.

If you have a small crew and primarily pump at the dock, this is a very
simple and workable set up.

Someone will point out the lack of a vented loop on the discharge. Save
your fingers. The through hull is only open when pumping and never needs to
be operated by a crew or guest. Even if it was left open, the water would
have to flow against two one way valves in the pump, fill the tank, and then
flow against the joker valve. It might sink the boat after a few weeks at
the dock but it's on the leaving boat checklist. Not having to pump
through the longer pipe or having a siphon break to leak odors from a dirtly
line makes the very slight risk worthwhile. If I ever need a survey for
insurance, I'm sure I'll have a fight with the surveyor though.

"krj" wrote in message
...
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve, and
through hull. The easiest way to mount the macerator pump is to screw it
into the outlet of the tank then plumb to the y-valve. Question is, will
the pump out be able to suck through the pump or can I turn the pump on
while pumping out the tank. Also is there any problem with pushing stuff
through the Y-valve rather than pulling through the valve.
Thanks
krj

krj wrote:
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve,
and through hull. The easiest way to mount the macerator pump is to
screw it into the outlet of the tank then plumb to the y-valve. Question
is, will the pump out be able to suck through the pump or can I turn the
pump on while pumping out the tank. Also is there any problem with
pushing stuff through the Y-valve rather than pulling through the valve.

It doesn't matter whether waste is pushed or pulled through a y-valve.

However, the pump, whether manual or electric, should be after the
y-valve. If it's ahead of the y-valve, it'll interfere with pumpout. A
particularly strong pumpout might be able to pull waste out of the tank
through the pump, but that much suction is likely to damage the pump.

You could eliminate the y-valve altogether by specifying two discharge
fittings in the tank...the hose from one goes directly to the deck
fitting...the hose from the other goes directly to the pump, vented loop
and overboard. That would allow you to connect the macerator directly to
the tank--but I don't recommend it 'cuz it increases the risk of
cracking the female fitting in the tank.
--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://shop.sailboatowners.com/books...ku=90&cat=1304

I've often wondered it this setup requires a "lock" on the pumpout to
comply with 33CFR159. Most descriptions of the reg refer to
"preventing accidental discharge" or securing a "direct discharge"
line. It would appear that the chance of an "accident" on your system
is essentially nil. Mine is similar, except that it includes a
y-valve to allow for either a manual pump discharge, or a deck
pumpout. Since the y-valve looks like one that might permit direct
discharge, I often keep a cable tie on it. I could also lock the
hatch or hide the pump handle, but I'd probably lose the key or handle!

Unfortunately, the actually CFR doesn't actually mention "accidental"
or "direct discharge." It more generally requires securing any means
of discharge. If the holding tank is considered part of the MSD Type
III system, then it would seem its pumping system would be included.

33CFR159.7


Roger Long wrote:
I've had very good luck with this very simple set up shown on this and the
following page.

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

No "Y" valve, no macerator pump. You have to pump by hand but, hey, we
could all use a little exercise at our age.

....

No, you don't have to have a Y valve. I have two separate discharges
from my holding tank. One goes to the macerator pump for overboard
discharge, the other goes to the deck pump-out. No Y valve and
completely legal. The pump can only be operated with a key switch, and
that's legal as a lock-out.

Peggie Hall wrote:
krj wrote:
Peggy,
I am re-plumbing my holding tank to include a macerator pump, Y-valve,
and through hull. The easiest way to mount the macerator pump is to
screw it into the outlet of the tank then plumb to the y-valve.
Question is, will the pump out be able to suck through the pump or can
I turn the pump on while pumping out the tank. Also is there any
problem with pushing stuff through the Y-valve rather than pulling
through the valve.

It doesn't matter whether waste is pushed or pulled through a y-valve.

However, the pump, whether manual or electric, should be after the
y-valve. If it's ahead of the y-valve, it'll interfere with pumpout. A
particularly strong pumpout might be able to pull waste out of the tank
through the pump, but that much suction is likely to damage the pump.

You could eliminate the y-valve altogether by specifying two discharge
fittings in the tank...the hose from one goes directly to the deck
fitting...the hose from the other goes directly to the pump, vented loop
and overboard. That would allow you to connect the macerator directly to
the tank--but I don't recommend it 'cuz it increases the risk of
cracking the female fitting in the tank.
Thanks Peggy,
I guess I will go with the conventional hookup.
krj

I remove the thru hull handle and keep it cable tied to the hose. No way
anyone will confuse it with inlet valve and I'm covered if the Coast Guard
boards.

"Jeff" wrote in message
. ..
I've often wondered it this setup requires a "lock" on the pumpout to

--
Roger Long