Black/toilet waste pump-out pump

[coopec43]

I have a manual toilet and I'm going to use a macerator to pump the sewage into a holding tank.

What sort of pump should I use to empty the sewage overboard? Cost is a factor where a breakdown is little more than an annoyance so I'm considering a $30 diaphragm pump but it would only pump about a gallon a minute. (If I want to pump it faster the pump will cost $100+ more)

DESCRIPTION
Features:
Durable rubber feet for reduced vibration
Long life
Runs dry without damage
Self Priming
Built-in Check Valve
Easy Installation
Volts: 12V/24V
Flow: 5.5L/Min
Power: 80W
Pressure: 0.9Mpa

Package including：
1 x Water Pump

[gulfstar37]

May want to consider a pump that is designed for what your trying doing. They will have a larger inlet / outlet to pass gunk. The one pictured above even states on label it requires an inlet filter. If pumping black tank contents the filter will plug up within seconds. If left off, the pump will plug up in short order.

The macerator pump you mentioned or a manual diaphram pump designed to pass sewage may be a better option.

[coopec43]

Originally Posted by gulfstar37

May want to consider a pump that is designed for what your trying doing. They will have a larger inlet / outlet to pass gunk. The one pictured above even states on label it requires an inlet filter. If pumping black tank contents the filter will plug up within seconds. If left off, the pump will plug up in short order.

The macerator pump you mentioned or a manual diaphram pump designed to pass sewage may be a better option.

Thanks Gulfstar.

I tend to have your reservations too but the sewage has already gone through a macerator as it is pumped into the holding tank so I thought it would be a black liquid.

The filter on the pump would be required because these pumps are used for drinking water. I'd like to see a lot bigger diameter inlet/outlets though.

I can get another 24V Macerator pump for $109 that pumps 45 lpm so maybe that's they way I have to go. It seems silly to have one macerator after another.

The schematic drawing was prepared by someone else but I am following the same idea. It is the diaphragm pump that I am deliberating about.


Clive

[Sailmonkey]

You have a macerator after a manual head?

That’s a lot odd?

Pump the manual head direct to the tank and use the macerator to drain the tank.

Better yet, do away with the macerator and use this to drain the tank

[coopec43]

[QUOTE=Sailmonkey;2793559]You have a macerator after a manual head?

That’s a lot odd?

Pump the manual head direct to the tank and use the macerator to drain the tank.

Better yet, do away with the macerator and use this to drain the tank

Attachment 183108[/QUOTE



If you have a macerator toilet the sewage ends up in the holding tank which must then be pumped overboard with a pump. That is not much different to what I am doing.

The pump pictured in your post looks like a gulper pump which cost $434 in Australia and I am trying to avoid Rolls Royce solutions.

Thanks for your thoughts

Clive

[Sailmonkey]

Imho, if you’re trying to avoid rolls Royce solutions, pump the manual head into the tank, and use the macerator to drain the tank.

The two pumps (three really when you count the head pump) is complex overkill.

If you want simple and effective, put the holding tank above the waterline and use gravity to drain it. We’ve been plumbed this way for 10 years and have not had a clog yet.

[atoll]

[QUOTE=coopec43;2793570]

Originally Posted by Sailmonkey

You have a macerator after a manual head?

That’s a lot odd?

Pump the manual head direct to the tank and use the macerator to drain the tank.

Better yet, do away with the macerator and use this to drain the tank

Attachment 183108[/QUOTE



If you have a macerator toilet the sewage ends up in the holding tank which must then be pumped overboard with a pump. That is not much different to what I am doing.

The pump pictured in your post looks like a gulper pump which cost $434 in Australia and I am trying to avoid Rolls Royce solutions.

Thanks for your thoughts

Clive

build the tank above the waterline then use gravity to drain it if you want to avoid buying a pump.
pump out stations generally have their own pump to suck out the contents of the tank

[coopec43]

[QUOTE=atoll;2793574]

Originally Posted by coopec43

build the tank above the waterline then use gravity to drain it if you want to avoid buying a pump.
pump out stations generally have their own pump to suck out the contents of the tank

I considered a tank above the waterline and it is not possible (not enough room) so mine is below the waterline.

Toilet systems have evolved a lot over the last 20 years - particularly because of environmental concerns regarding dumping waste at sea.

There doesn't seem to be one right system: the chandlers who supplied my components told me what to do. (Apparently there are less blockages with macerators than with manual pumps)

All I want is a diaphragm pump with a decent output and at the right price.

Clive

[ranger58sb]

Originally Posted by coopec43

What sort of pump should I use to empty the sewage overboard?

Our macerator pumps -- one to empty the holding tank, one to empty the fishbox -- are Jabsco 18590-series, and assuming those are still current model numbers, 2092 = 12V; 2094 = 24V. Given it's a macerator, I think it's not a diaphram pump.

Details on the Xylem website.

Can't say whether they work better or worse than other similar pumps, and we don't use our holding tank pump very often... but the fishbox pump chucks out ace and scales and so forth without problems.

-Chris

[Sailmonkey]

[QUOTE=coopec43;2793595]

Originally Posted by atoll

All I want is a diaphragm pump with a decent output and at the right price.

Clive

What you posted a photo of in your original post is not even remotely the correct pump.

A decent diaphragm pump, while not really worth what they cost, is the correct option. Maybe you can find a knock off brand on eBay or alibaba....just be sure the diaphragm material is up to the task.

Regarding the setup you described.....in the last 20 years, that technology has changed zilch. Putting an electric macerator downstream of a manual head is folly. It may work slick for a while, but imho you’re adding unneeded complexity to what should be a very simple system.

Added complexity using inferior components means you will at some point be handling poo water.

[peghall]

Adding a macerator pump to a manual toilet is a bad idea. If the toilet isn't pumped fast enough to keep up with the macerator, the macerator will run dry which will fry the impeller in it. If it's pumped ahead of turning on the macerator pump, the flush has nowhere to go until the macerator is turned on.

Any manual toilet that's working anywhere near factory spec can move bowl contents to a holding tank. Solids get broken up by the pump, and dissolve very quickly in the tank, so macerating waste isn't necessary anyway.

So either stick with a manual toilet and install a macerator or manual diaphragm pump to dump the tank at sea, or replace the manual toilet with an electric macerating toilet. You'll have nothing but problems if you try to create a combined manual and electric toilet.


--Peggie

[boat driver]

Originally Posted by coopec43

Thanks Gulfstar.

I tend to have your reservations too but the sewage has already gone through a macerator as it is pumped into the holding tank so I thought it would be a black liquid.

The filter on the pump would be required because these pumps are used for drinking water. I'd like to see a lot bigger diameter inlet/outlets though.

I can get another 24V Macerator pump for $109 that pumps 45 lpm so maybe that's they way I have to go. It seems silly to have one macerator after another.

The schematic drawing was prepared by someone else but I am following the same idea. It is the diaphragm pump that I am deliberating about.


Clive

The schematic is correct depending on the tank design- but ideally head discharge into tank top- then bottom drain as described and install macerator or decent large inlet pump post the T fitting to deck-
as well add a ball valve at the tank discharge before the T fitting- this provides three opportunities- if the seacock/macerator gets dried out and/or clogs- close valve and flush with deck wash 2) if the tank sits for storage and/or period of time it can dry out and get "solid" - close seacock and fill tank with deck wash then after time flush 3) if need to work on macerator /pump I will bet the tank will not be empty.........

If tank can get above the waterline then gravity will take care of needing the macerator or any pump.

In my gravity system (manual head-plastic tank inlet at top-drain in bottom of tank-valve - T valve to deck/overboard- seacock ) is to keep the tank valve closed and keep some liquid in tank- then drain when I am offshore or pumping out via deck fitting- I discovered that this provides better tank flush vs leaving valve open constantly when offshore.

[Tayana42]

I use a Whale Gusher Titan with a nitrile diaphragm to empty my holding tank when beyond the 3 mile limit. I have a VacuFlush toilet to 30 gallon holding tank that empties to deck pump out or the Gusher Titan connected to a below the waterline through hull for discharge.

[Cpt Mark]

Many manual heads can be converted to an electric head with an appropriate kit which is the way to go rather than trying to jury rig something.

My personal experience though is that they work great for a while and then they don't.

If you want an electric head, then buy a good one that is designed from the ground up. Yes, heads have changed in the last 20 years just as home toilets have changed with more effective water swirling action.

Practical Sailer has a good review on the various models. I put a Raritan Marine Elegance on board and absolutely love it.

Regarding pump out. My boat has a macerator pump which came with the boat so I'm not going to replace it and not sure I would anyway. It is designed for sewage and that is one area where I never want problems. I. did have to install a new Y valve just ahead of the macerator and install new hoses. Ugly job. If you do install new hoses use the new generation like Vetus. Expensive yes but so flexible and easy to work with and contents will not permeate. Also use T-bolts instead of standard hose clamps.

Do it right once and be done with it. Otherwise you're in for a lot of gross mistakes.

[peghall]

Many manual heads can be converted to an electric head with an appropriate kit which is the way to go rather than trying to jury rig something.

The Jabso 29200 "conversion" replaces the manual pump with a macerating electric pump. Not even Jabsco recommends it. The Lavac can be converted to electric by replacing the manual diaphragm pump with their electric motor kit. The Raritan PHII and the Groco Model K can be "converted" to electric by adding an electric motor that only replaces the pump HANDLE, which turns two outstanding manual toilets into the worst excuse for an electric toilet ever conceived and costs more than a real electric macerating toilet.


My personal experience though is that they work great for a while and then they don't.

"Great" would be a huge overstatement for most of 'em.


--Peggie