macerator not emptying holding tank

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What is a diaphragm pump? I am not familiar. Can you give me a brand/model so that I may research.

I will install PVC ball valves after the PVC T to be able to isolate the macerator from the deck pump out.
 
jclays said:
What is a diaphragm pump? I am not familiar. Can you give me a brand/model so that I may research.

I will install PVC ball valves after the PVC T to be able to isolate the macerator from the deck pump out.
Click to expand...

Look up Dometic Sealand discharge pump.

Your plumbing set up is fine. My boat is plumbed the same way. As long as there’s a valve or seacock and it is closed when at the pump out it should be fine.

Like others have suggested, make sure that you don’t have a vacuum leak at the deck fitting by making sure the lid o-ring is in good shape.
 
The delivery captain had the boats tank pumped out and cleaned. The seasick was open . Would that damage the macerator? It runs fine it just doesn’t pump the tank of water out.
 
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Lack of use is a likely culprit. You're only guessing until you get in there and see with your eyes. A shop vac will suck up any small amount of bleach water that might seep out. Can you get to it before the weekend?
 
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jclays said:
The delivery captain had the boats tank pumped out and cleaned. The seasick was open . Would that damage the macerator? It runs fine it just doesn’t pump the tank of water out.
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Which type of discharge pump do you have? I know you call it a macerator, but some folks call their discharge pumps that even if it's really a diaphragm type. If it's the latter, there is a chance that the duckbills are inverted and will need to be straightened or replaced. If you have the macerating type, I don't think vacuum going through it did any harm - but I'm not certain.
 
jclays said:
The delivery captain had the boats tank pumped out and cleaned. The seasick was open . Would that damage the macerator? It runs fine it just doesn’t pump the tank of water out.
Click to expand...

Running a true macerator pump dry (or without flow) for more than a minute will destroy the impeller. Not knowing the history consider the impeller toast
 
mahal thanks for the vacuum tip .

i looked up the 300 $ sealand pump there instructions are contradicting themselves they say you need a vented loop/siphon break between and the thru hull ? that would damage the duck bill like the seacock open .but on there same instructions the diagram does not show one?
 
timb said:
mahal thanks for the vacuum tip .

i looked up the 300 $ sealand pump there instructions are contradicting themselves they say you need a vented loop/siphon break between and the thru hull ? that would damage the duck bill like the seacock open .but on there same instructions the diagram does not show one?
Click to expand...

I installed mine as a direct replacement for a GalleyMaid macerator with no siphon break. Just a direct hose from the tank to pump and from the pump to seacock, works just fine for the past 9 months.
 
Do the diaphragm pumps work with a vacuflush toilet?
 
Sea land sells a pump called a Trash pump or T pump. While it’s not exactly a diaphragm pump it is very similar. It is in fact the same pump as the vacuum generator pump minus 1 pair of duck bill valves and sells for a third the price of the vacuum generator. The best part is you can rob parts off of the T pump in a vacuflush emergency. Running dry or priming are non issues with the T pump. Reliability and longevity are the T pumps strength.
 
jclays said:
Do the diaphragm pumps work with a vacuflush toilet?
Click to expand...

I think the vacuum pump has 4 joker valves, 2 on the input and 2 on the output. The regular pump only has 1 on each side. There is supposed to be a way to modify the pump for 4 joker valves but it is something about reverse threads because they want to sell the more expensive vacuum pump.
 
I will install PVC ball valves after the PVC T to be able to isolate the macerator from the deck pump out.

You don't need a ball valve there, you need a diverter valve...aka "y-valve." (see attached photo for a typical example)


Do the diaphragm pumps work with a vacuflush toilet?

The holding tank is not a component in a VacuFlush system...the vacuum pump is the last component. It pushes the flush to the tank, same as any other toilet does. So any type of pump--manual, macerator, or diaphragm--that can be used to dump a holding tank connected to any other toilet will work to dump a holding tank connected to a VacuFlush toilet.


i looked up the 300 $ sealand pump there instructions are contradicting themselves they say you need a vented loop/siphon break between and the thru hull ? that would damage the duck bill like the seacock open .but on there same instructions the diagram does not show one?

No contradiction...all overboard discharge pumps including the Dometic/SeaLand T-Pump pull waste out of the tank and push it overboard, whether or not through a vented loop. So the tank contents move through the duckbill valves the "right" direction. A vented loop prevents sea water from starting a siphon if the thru-hull is left open when not actually in use dumping a tank,so there shouldn't be any pressure against the duckbill valves. The instructions for the T-Pump don't show a vented loop because it's totally separate from it and may not be needed in above waterline installations.

--Peggie
 

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HeadMistress said:
I will install PVC ball valves after the PVC T to be able to isolate the macerator from the deck pump out.

You don't need a ball valve there, you need a diverter valve...aka "y-valve." (see attached photo for a typical example)


Do the diaphragm pumps work with a vacuflush toilet?

The holding tank is not a component in a VacuFlush system...the vacuum pump is the last component. It pushes the flush to the tank, same as any other toilet does. So any type of pump--manual, macerator, or diaphragm--that can be used to dump a holding tank connected to any other toilet will work to dump a holding tank connected to a VacuFlush toilet.


i looked up the 300 $ sealand pump there instructions are contradicting themselves they say you need a vented loop/siphon break between and the thru hull ? that would damage the duck bill like the seacock open .but on there same instructions the diagram does not show one?

No contradiction...all overboard discharge pumps including the Dometic/SeaLand T-Pump pull waste out of the tank and push it overboard, whether or not through a vented loop. So the tank contents move through the duckbill valves the "right" direction. A vented loop prevents sea water from starting a siphon if the thru-hull is left open when not actually in use dumping a tank,so there shouldn't be any pressure against the duckbill valves. The instructions for the T-Pump don't show a vented loop because it's totally separate from it and may not be needed in above waterline installations.

--Peggie
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Looks like an in-line ball valve on the line to the macerator and one on the line to the deck pump out would do the same thing as the deserter Y valves without disassembling my plumbing and positioning my waste tank.
 
Anyone have experience with the Whale Gulper Toilet Pump compared to the Sealand T12?

https://www.whalepumps.com/marine/p..._ID=10016&FriendlyID=Whale-Gulper-Toilet-Pump

Both run dry without damage.

I've had T12s on two boats and they generally work well. BUT, at least a few times a year, something gets caught on the duckbill (usually the intake side, one time it was a popcorn kernel) and the pump won't prime. It's not that difficult or time consuming to clear the debris or replace the duckbill, but it's not a particularly pleasant job.

The Gulper Toilet Pump has two duckbills on each side, so both would have to be obstructed for the pump not to function. Seems like it might be an improvement, and I've had great luck with other Gulper pumps.

Thoughts?
 
jclays said:
Looks like an in-line ball valve on the line to the macerator and one on the line to the deck pump out would do the same thing as the deserter Y valves without disassembling my plumbing and positioning my waste tank.
Click to expand...

How can installing TWO ball valves--one in each hose--be simpler than just replacing the tee that's already installed in the tank discharge line with a y-valve?

--Peggie
 
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Access to t limited up against bulkhead. Can install ball valves on each line clear of obstructions
 
The macerator output thru hull is out the bottom of the hull. Is this normal?
 
jclays said:
The macerator output thru hull is out the bottom of the hull. Is this normal?
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Not sure there is a normal, but it has been so on my two boats.
 
jclays said:
The macerator output thru hull is out the bottom of the hull. Is this normal?
Click to expand...

That is how mine have been. You don’t really want the sewage running down the side of the hull...
 
Had our holding tank macerator pump crap out a few months ago, well away from civilisation and interwebs.
Had to replumb one of the macerating electric toilets to direct overboard (above waterline) as our 105 gallon holding thank was chocablock
Pulled pump apart and the impeller had lost its blades.

Got back to interwebs range a week later and ordered a cheap yum cha 24v pump and a replacement impeller kit to meet us further up the track.
Then about 14 days to arrive.

Cheap pump working fine
Original Johnson pump rebuilt and in the spares cupboard.
Not getting caught out again.
 
Comodave said:
You don’t really want the sewage running down the side of the hull...
Click to expand...

Ours is above the waterline
Boat only has 2 through hulls, Main engine and genset/deckwash

Passing waves and wash when underway keep the hull side clean.
 
My OB pump went down last week and I wont be able to replace it until I get home in about two weeks and no pump out station where I am. It’s just me as of today, so its manageable. Just thankful to be on the boat, especially now, so these are just small inconveniences.
 
I decided after reading this conversation that I should probably buy a spare pump for Sonas and put it on board as there are zero pump out facilities in the islands. So we lifted the hatch and took a photo of the "pump!"

So before I can buy I am going to have to wait until my back is OK enough to get down and take this cover off to see which diaphragm pump model I have!

I suspect it is a T series.
 

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menzies said:
BTW, this is probably a god place to pontificate on one of my mantras.

Start with the most simplest (and in most case cheaper) resolution first and work your way towards the more complicated (and usually more expensive ) solutions.

This is a lesson borne of implementing fixes which cost more, only to find a 50c solution fixed the problem!

Good luck!
Click to expand...
The KIS method works for me.
 
menzies said:
I decided after reading this conversation that I should probably buy a spare pump for Sonas and put it on board as there are zero pump out facilities in the islands. So we lifted the hatch and took a photo of the "pump!" I suspect it is a T series.
Click to expand...


You guessed correctly..it is a Dometic/SeaLand T-Pump. There's only one...no "series."



--Peggie
 
Nope...that depends entirely on whether the DC power system on your boat is 12v or 24v...something that will affect which "version" all the DC powered equipment on your boat needs to be. At least 95% of boats have 12v systems. If you're in any doubt about which whether your boat's system is 12v or 24v, it should be clearly indicated on the label of the pump you need to replace and/or your water pump, electric toilet pump/motor assembly, washdown pump.....


--Peggie
 
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