Holding tank manual pump issue

Dec 4, 2020
15
Hunter 28.5 Wilmington Island
I had some trouble sufficiently pumping out my holding tank recently at a marina. I believe the issue is with the manual pump (photo attached)

I'm having trouble finding that specific pump to replace, anyone have an alternative suggestion or recommendation?

20201208_132423.jpg
20201208_132418.jpg
 
Dec 4, 2020
15
Hunter 28.5 Wilmington Island
Oct 22, 2014
16,082
CAL 35 Cruiser moored EVERETT WA
Sure looks like the solution.

Nice pictures @Sandfly. Welcome to the forum. When you post pictures like that it is sometimes very easy for other boat owners to suggest a solution.

Let us know how you did with solving your pump problem.
 
Dec 2, 1997
8,120
- - LIttle Rock
I had some trouble sufficiently pumping out my holding tank recently at a marina.
"...at a marina" implies that you were trying pump out using the marina's pumpout equipment. If so, you shouldn't be trying to use an onboard pump...the pumpout sucks the waste out of the tank...an onboard pump in the pumpout line from the tank to the deck pumpout fitting would create a blockage that would make it impossible for the pumpout pull out much if anything. On most boats the onboard pump is usually in a line from the tank to a thru-hull.

Am I missing something here?

--Peggie
 
Jan 7, 2011
2,908
Oday 322 East Chicago, IN
"...at a marina" implies that you were trying pump out using the marina's pumpout equipment. If so, you shouldn't be trying to use an onboard pump...the pumpout sucks the waste out of the tank...an onboard pump in the pumpout line from the tank to the deck pumpout fitting would create a blockage that would make it impossible for the pumpout pull out much if anything. On most boats the onboard pump is usually in a line from the tank to a thru-hull.

Am I missing something here?

--Peggie
Maybe the torn diaphragm is creating an air leak, so he cannot pull a vacuum with the pumpout pump?

I am not sure where that pump is located in his plumbing.

But it does look more like a manual bilge pump than a sewage pump.

Greg
 
Dec 4, 2020
15
Hunter 28.5 Wilmington Island
"...at a marina" implies that you were trying pump out using the marina's pumpout equipment. If so, you shouldn't be trying to use an onboard pump...the pumpout sucks the waste out of the tank...an onboard pump in the pumpout line from the tank to the deck pumpout fitting would create a blockage that would make it impossible for the pumpout pull out much if anything. On most boats the onboard pump is usually in a line from the tank to a thru-hull.

Am I missing something here?

--Peggie
From what I understand through what the former owner told me when we bought it 2 months ago (this is my first boat so I'm still learning a lot) was that this pump can be used as an alternative to using a pump out house for when offshore. The head islocated behind that pump. The hose running from the T below the pump, under that blue brush runs directly up to the deck for the a pump out house. When we tried to use the pump put house, you could hear air excaping from that manual pump.

Thank you for your responce by the way!
 
Dec 4, 2020
15
Hunter 28.5 Wilmington Island
Maybe the torn diaphragm is creating an air leak, so he cannot pull a vacuum with the pumpout pump?

I am not sure where that pump is located in his plumbing.

But it does look more like a manual bilge pump than a sewage pump.

Greg
I belieive that air leak is what is happening.
 
Jan 7, 2011
2,908
Oday 322 East Chicago, IN
I belieive that air leak is what is happening.
Sounds like that is the issue. If you can find the right replacement diaphragm, that could be your solution. Or remove the diaphragm pump all together...

You have to be at least 3 miles off shore to use it anyway...

Greg
 
Dec 4, 2020
15
Hunter 28.5 Wilmington Island
Sounds like that is the issue. If you can find the right replacement diaphragm, that could be your solution. Or remove the diaphragm pump all together...
yeah it's so old I don't think I'll find an exact replacement, I figured removing it and closing the loop would be the easiest solution.
 
Dec 2, 1997
8,120
- - LIttle Rock
First...this is your first boat and you can take comfort in knowing that NONE of us were born knowing anything about how systems on boats are supposed to work!

From what I understand through what the former owner told me when we bought it 2 months ago (this is my first boat so I'm still learning a lot) was that this pump can be used as an alternative to using a pump out house for when offshore.
Aha! The operative phrase in that is "this pump can be used as an alternative to using a pump out house for when offshore." That's true, but each function--pumpout and (for lack of a better term) "dump out"-- are two separate functions that use separate plumbing.

Follow me thru-this: Holding tank plumbing starts with a hose from the toilet (inlet hose), a hose from the tank to the pumpout fitting (tank discharge hose) and a vent line that provides an escape for air inside the tank displaced by incoming waste and a source of air to replace contents as they're pumped out or dumped.
There can be a diverter valve (aka "y-valve") in the tank discharge line It creates an "intersection" that allows you to choose between pumping out or dumping. If you look at the photo, you'll see it has an inlet fitting and two outlet fittings...the hose from the tank connects to the inlet fitting, a hose that goes directly to the deck pumpout fitting goes to one of the outlet fittings, and another line that goes to a thru-hull comes off the the other outlet fitting...and it's in THAT line that a pump belongs. Ideally there'd actually be TWO tank discharge lines, which eliminates the need for a y-valve.

That should be enough to completely confuse you till you've read it several times. Once you've managed to sort it all out, it should explain why you couldn't pump out. I'm available to answer all your questions, here or one-on-one if you'd like to send me a PM.

And btw...yes, you do need to replace that pump...and all the hoses...and I can't see how much else.

Happy New Year!
bosworth y-valve.gif
 

SFS

.
Aug 18, 2015
1,972
West Marine Kayak Tampa Bay
Peggie knows everything there is to know about this topic, so her advice is priceless. She has helped many of us, and is happy to talk to you as she has said. Don't miss out on this valuable resource.

And buy her book. Every boat owner should have a copy.
 
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