I'd be interested in views as to whether a macerator pump should be
installed higher than the holding tank.

Background: On my boat, the macerator (Jabsco) is installed on top of
the waste tank (about 2 feet high). Although it's supposedly
"self-priming", it only functioned if the tank was completely full,
and then it would only take out a gallon or two. Ultimately, the
impeller self-destructed.

Armed with a new impeller, I am now considering installing it at the
same level as the base of the holding tank. I'd think it would then
be more likely to prime, and actually pump. The only down-side I see
is that it would be constantly "loaded" with waste (unlike now, where
the residual waste presumably drains back down the hose to the tank
level). But if the pump seals are good, I figure that's not a
problem?

Am I missing anything?

I'd appreciate any views.

On 29 Jul 2003 11:41:39 -0700, (WF) wrote:


The only down-side I see
is that it would be constantly "loaded" with waste (unlike now, where
the residual waste presumably drains back down the hose to the tank
level). But if the pump seals are good, I figure that's not a
problem?

Am I missing anything?


Possibly a check valve in front of the macerator so it isn't
constantly loaded. Mine has one. Close the valve then turn the
macerator off.



Jeannette Bristol 32, San Francisco
http://www.eblw.com/contepartiro/contepartiro.html

It'll only be a problem if you ever have to remove the pump while the tank
is full. Yuk. I installed a Sealand T-series diaphragm pump that is self
priming and can run dry forever without damage. All my holding tank fittings
enter through the top of the tank. I also have separate discharge
fittings... one to the pump and one to the deck fitting. That way I don't
have a Y valve to mess with or leak.

--


Keith
__
A pessimist's blood type is always b-negative.
"WF" wrote in message
om...
I'd be interested in views as to whether a macerator pump should be
installed higher than the holding tank.

Background: On my boat, the macerator (Jabsco) is installed on top of
the waste tank (about 2 feet high). Although it's supposedly
"self-priming", it only functioned if the tank was completely full,
and then it would only take out a gallon or two. Ultimately, the
impeller self-destructed.

Armed with a new impeller, I am now considering installing it at the
same level as the base of the holding tank. I'd think it would then
be more likely to prime, and actually pump. The only down-side I see
is that it would be constantly "loaded" with waste (unlike now, where
the residual waste presumably drains back down the hose to the tank
level). But if the pump seals are good, I figure that's not a
problem?

Am I missing anything?

I'd appreciate any views.

It's self priming to 5' when the impeller is wet, 4' when it's dry, Steve.

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://www.seaworthy.com/html/get_ri...oat_odors.html


Steve wrote:
To my knowledge, the Jabsco centrifugal macerator IS NOT self priming and is
suppose to be installed below the liquid level of the tank.. I think I
remember reading this in the installation instructions for one I had
purchase in error.

For me, this it the reason I had to go to a Sealand diaphram pump (no way to
get the pump lower than the tank bottom).

Perhaps Peggy Hall can shed some light on this.

jeannette wrote:
Possibly a check valve in front of the macerator so it isn't
constantly loaded. Mine has one. Close the valve then turn the
macerator off.

Not a check valve...a y-valve (aka diverter valve) that allows you to
choose between pumping out or going to the macerator.

However, whether the boat should even HAVE a macerator or any other pump
to dump the tank depends on whether the boat is in coastal waters that
provide immediate access to open sea...'cuz it's illegal to dump a tank
in ANY US waters....only when at least 3 miles out to sea. And that
doesn't mean 3 miles from shore in a lake, river, bay or sound...it
means 3 miles from the nearest point on the whole North American
coastline. So unless he has immediate access to open sea, he might as
well just remove the macerator altogether...'cuz the fines for dumping a
tank illegally are very steep.

Interesting comment Peggy. I live aboard and boat in the great lakes.
Pumped out every two weeks or so.

When you say "When, if ever, have you rinsed out the tank"

I am lead to ask two questions:

1) How often do you think this needs to be done?
2) What do you mean by rinsed out?

At each pump out, I pump out, then fill the tank with a few gallons of
water, then pump out again. If I feel like it, I do that twice. Is that
enough, or are you suggesting filling the tank, going for a sail to
slosh it up and then pumping out?

I REALLY do not want to have to open the tank inspection ports, so
anything I can do to minimize the possibility I will do! I do not use
chemicals in the head. I did, but found that it was a never ending cycle
of adding more blue liquid to mask the smell.

Instead, I use a powder made for septic systems that grows a bacteria of
some sort in the tank. The blue liquid would kill that bacteria. Since I
started using this powder the head has exhibited almost no smell. That
is except when I get a pump out. After a pump out the whole boat just
REEKS. I figured out why just recently. I believe that the pump out
empties the hose to the head too, and in so doing, opens a direct path
to allow the tank vapors to enter the cabin. Only reason I think so is
because I can remove the smell by pumping a cupfull of water into the head.

Anyway, just wanted to ask my questions. Thanks for all the advice I
have read over the years here. You really have helped a lot of folks by
sharing your knowledge!



Peggie Hall wrote:
WF wrote:

I'd be interested in views as to whether a macerator pump should be
installed higher than the holding tank.


Within the limits set by the macerator mfr, yes...it can be.


Background: On my boat, the macerator (Jabsco) is installed on top of
the waste tank (about 2 feet high). Although it's supposedly
"self-priming", it only functioned if the tank was completely full,
and then it would only take out a gallon or two. Ultimately, the
impeller self-destructed.


That sounds like a blocked tank vent causing the pump to pull a vacuum,
not a problem with the macerator location. Or a blockage in the tank
discharge line. When, if ever, have you rinsed out the tank to get rid
of sludge accumulation on the bottom of it? 'Cuz macerators aren't that
powerful..a hoseful of sludge that can't make it through the pump can
stop one cold.

Armed with a new impeller, I am now considering installing it at the
same level as the base of the holding tank. I'd think it would then
be more likely to prime, and actually pump.


Moving the macerator might extend the life of the impeller a little by
cutting the time it takes to prime from 2-3 seconds to 1...but I don't
think the current location is the problem.

The only down-side I see
is that it would be constantly "loaded" with waste (unlike now, where
the residual waste presumably drains back down the hose to the tank
level). But if the pump seals are good, I figure that's not a
problem?


That problem can easily be solved--and should be--by putting a y-valve
in the tank discharge line instead of only a tee fitting. I say "should
be" because macerators never fail when a tank is empty...you need to be
able to cut off the flow of waste to the pump to work on it.

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://www.seaworthy.com/html/get_ri...oat_odors.html





Am I missing anything?

I'd appreciate any views.

On Tue, 29 Jul 2003 21:16:43 GMT, Peggie Hall
wrote:

jeannette wrote:
Possibly a check valve in front of the macerator so it isn't
constantly loaded. Mine has one. Close the valve then turn the
macerator off.

Not a check valve...a y-valve (aka diverter valve) that allows you to
choose between pumping out or going to the macerator.

No I did mean a check valve in front of the macerator. The Y valve is
just after the toilet. It diverts to either the tank or overboard. The
checl valve is between the tank and the macerator pump. I open it
before turning the pump on and turn it off when done. I used it twice
so far in 2 years when I got out of the San Francisco Bay, past the 3
miles limit.

I do have a question for you Peggie. I am looking for a Tank Level
Monitor. I saw some time ago a system that worked with sensors on the
outside of the tank. My tank is fiberglass. Do you (or anyone) know
where I can find that?

Jeannette


However, whether the boat should even HAVE a macerator or any other pump
to dump the tank depends on whether the boat is in coastal waters that
provide immediate access to open sea...'cuz it's illegal to dump a tank
in ANY US waters....only when at least 3 miles out to sea. And that
doesn't mean 3 miles from shore in a lake, river, bay or sound...it
means 3 miles from the nearest point on the whole North American
coastline. So unless he has immediate access to open sea, he might as
well just remove the macerator altogether...'cuz the fines for dumping a
tank illegally are very steep.





Jeannette Bristol 32, San Francisco
http://www.eblw.com/contepartiro/contepartiro.html

When you say "When, if ever, have you rinsed out the tank"

I am lead to ask two questions:

1) How often do you think this needs to be done? 2) What do you mean
by rinsed out?

At each pump out, I pump out, then fill the tank with a few gallons
of water, then pump out again. If I feel like it, I do that twice. Is
that enough, or are you suggesting filling the tank, going for a sail
to slosh it up and then pumping out?

That's enough most times--and good on ya...'cuz most people don't ever
bother to do that much. Only other thing I'd recommend is, a few times
a season it should be repeated until what's being pumped out is just
clean water.

I REALLY do not want to have to open the tank inspection ports, so
anything I can do to minimize the possibility I will do! I do not use
chemicals in the head. I did, but found that it was a never ending
cycle of adding more blue liquid to mask the smell.

Instead, I use a powder made for septic systems that grows a bacteria
of some sort in the tank.

You're on the right track by avoiding chemicals...but septic tank
enzymes are cultured for use in anaerobic systems--holding tanks have to
be aerobic to prevent odor. If the septic tank enzymes were really
working in the tank, you wouldn't have any odor when you pump out. That
means the waste in your tank still stinks.

Since I started using this powder the head has exhibited almost no
smell. That is except when I get a pump out. After a pump out the
whole boat just REEKS. I figured out why just recently. I believe
that the pump out empties the hose to the head too, and in so doing,
opens a direct path to allow the tank vapors to enter the cabin. Only
reason I think so is because I can remove the smell by pumping a
cupfull of water into the head.

All that's doing is providing a water barrier to prevent the odor from
the tank from escaping into the boat. Pumping out should not pull air
through the head...that's an indication that the tank vent isn't
allowing enough air into the tank to replace the waste being pulled out
by the pump out. That may be due to a partially blocked vent, or it may
be due to a vent line that's too long and has too many bends in it...a
vent thru-hull in which the opening is too small (or at least partially
blocked), or vent line that has too small a diameter vs. a particularly
powerful pumpout.

Even so, odor shouldn't be able to escape through the head--the pumpout
is PULLING air into it, not pushing it out. That leads me to believe the
joker valve in the toilet is worn out...that it no longer closes.

Oxygen is the key to eliminating holding tank odor. When waste--or any
other organic matter--breaks down aerobically (oxygenated), the gasses
produced are odorless...but when it breaks down ANaerobically (without
oxygen), it produces foul smelling sulphurous gasses. So the solution to
your tank odor is increased ventilation to the tank. Investigate all the
things I mentioned above and correct what you can. I'd also recommend
that you switch from the stuff you're currently using to a product
called Odorlos. It's a Norwegian import, available at most marine
stores...the active ingredient is nitrates that promote oxygen release
from the waste itself. You can check it out on their website at
http://www. odorlos.com

Anyway, just wanted to ask my questions. Thanks for all the advice I
have read over the years here. You really have helped a lot of folks
by sharing your knowledge!

Always glad to help.

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://www.seaworthy.com/html/get_ri...oat_odors.html


Peggie Hall wrote:

WF wrote:

I'd be interested in views as to whether a macerator pump should
be installed higher than the holding tank.



Within the limits set by the macerator mfr, yes...it can be.


Background: On my boat, the macerator (Jabsco) is installed on
top of the waste tank (about 2 feet high). Although it's
supposedly "self-priming", it only functioned if the tank was
completely full, and then it would only take out a gallon or two.
Ultimately, the impeller self-destructed.



That sounds like a blocked tank vent causing the pump to pull a
vacuum, not a problem with the macerator location. Or a blockage in
the tank discharge line. When, if ever, have you rinsed out the
tank to get rid of sludge accumulation on the bottom of it? 'Cuz
macerators aren't that powerful..a hoseful of sludge that can't
make it through the pump can stop one cold.

Armed with a new impeller, I am now considering installing it at
the same level as the base of the holding tank. I'd think it
would then be more likely to prime, and actually pump.



Moving the macerator might extend the life of the impeller a little
by cutting the time it takes to prime from 2-3 seconds to 1...but I
don't think the current location is the problem.

The only down-side I see is that it would be constantly "loaded"
with waste (unlike now, where the residual waste presumably
drains back down the hose to the tank level). But if the pump
seals are good, I figure that's not a problem?



That problem can easily be solved--and should be--by putting a
y-valve in the tank discharge line instead of only a tee fitting.
I say "should be" because macerators never fail when a tank is
empty...you need to be able to cut off the flow of waste to the
pump to work on it.

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://www.seaworthy.com/html/get_ri...oat_odors.html





Am I missing anything?

I'd appreciate any views.

Peggie Hall wrote in message ...

I want to thank you for the Ordorlos suggestion from a previous
string. It seems to work much better than the "blue stuff".

When you mentioned a failed joker valve, my brother-in-law recently
had a JV failure mid-cruise (naturally). Not only was it ugly to
replace, he and his wife had to "visit" our boat regularly for the
last half of our 2-week cruise.

Which brings me to two questions: Do you recommend preventive
maintenance (Ugh!) on joker valves? And how reliable are Vacuflush
systems (more preventive maintenance?) My boat/Vacuflush is 13 years
old.

When you mentioned a failed joker valve, my brother-in-law recently
had a JV failure mid-cruise (naturally). Not only was it ugly to
replace, he and his wife had to "visit" our boat regularly for the
last half of our 2-week cruise.

Replacing a joker valve is one of the easiest jobs, Bob...you don't even
have to remove any hoses...just the two bolts that hold the discharge
fitting on the base. Nor should a joker valve failure prevent the head
from being used...If it WAS a nasty job and/or they couldn't use the
toilet, replacing the joker valve didn't cure the real problem...it just
hid it.

Which brings me to two questions: Do you recommend preventive
maintenance (Ugh!) on joker valves?

What's to maintain? A joker valve is just a rubber "cup" with a slit in
it and "lips"--a one-way valve. Over time, waste going through the slit
stretches it to the point where the slit is no longer a slit, it's a
hole...and useless any longer as a one-way valve. Then you replace it.
That's it. I'd flush a lot of clean water through it first, though.


And how reliable are Vacuflush
systems (more preventive maintenance?) My boat/Vacuflush is 13 years
old.

VacuFlush toilets are very reliable and require no preventive
maintenance...they're fine toilets (they just cost FAR more than ANY
marine toilet is worth). When it develops a symptom--pump starts cycling
for no reason between flushes, or won't shut off, or the water valve
leaks--fix it. If you don't have an owners manual for it, call SeaLand
and get one (800-321-9886)...'cuz every symptom, probable causes and
cures that it can develop is covered in it. The VacuFlush hasn't changed
enough to notice in the last 20 years, so just ask for the current
manual. And keep it on the boat so you can refer to it if/when it does
develop a symptom...'cuz blind seat-of-the-pants trouble shooting can
cause additional problems instead of solving the one you have.

I had VacuFlush toilets on two of my own boats, btw, and we were dealers
for nearly 10 years...so I'm intimately acquainted with it.

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://www.seaworthy.com/html/get_ri...oat_odors.html