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Discussion Starter #1 (Edited)
Hello everyone,

We've had a very sudden and baffling issue happen with our Groco KH-Manual head. We're in a Pacific Seacraft Crealock 34. In a strange situation, where everything was operating fine literally 15 minutes prior, the bowl would suddenly not empty with the Y-valve set to overboard discharge, and the pump developed significant back pressure in the system when trying to pump overboard. This happened during a routine cleaning of the system with a dilution of water and white vinegar, something we've done routinely over the past 17 years.

We can pump into the holding tank normally, with zero issues. And, as we're in a marina, we've used only salt water to test the overboard discharge. Just wanted to put that out there.

What we have done thus far:

Replaced the flapper valve and spring assembly
Replaced the joker valve
Replaced the bowl gasket
Removed and cleaned all system hoses, removing all scale and deposits until the hose interiors are reflective and clean
Replaced the Y-Valve with a new unit
Cleaned the nipples/tailpieces on the intake and discharge through-hull fittings
Tested the through hull fittings for proper operation
Cleaned the vented loops and valves
Had a trusted diver inspect the intake and discharge through hull fittings from the outside, including reaming/probing for obstructions

Short of catching us up on maintenance, none of this changed anything. We still cannot pump overboard from the head without developing significant back pressure/resistance, and the bowl does not empty. We can pump into the holding tank normally, no issues whatsoever. We've also noticed the static water level in the bowl is now hogher than it has been normally. The only thing we haven't done is a complete rebuild of the pump, (remember, we can pump into the holding tank with no issues), and the pump was fully reconditioned/rebuilt by Groco in 2015. Patrick at Groco said we should expect 7-10 years of trouble free operation. This instantaneous development is most frustrating.

I'm calling Groco on Monday.

Any Pacific Seacraft 34 owners want to share info on composting heads??
 

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Hello everyone,

We've had a very sudden and baffling issue happen with our Groco KH-Manual head. We're in a Pacific Seacraft Crealock 34. In a strange situation, where everything was operating fine literally 15 minutes prior, the bowl would suddenly not empty with the Y-valve set to overboard discharge, and the pump developed significant back pressure in the system when trying to pump overboard. This happened during a routine cleaning of the system with a dilution of water and white vinegar, something we've done routinely over the past 17 years.

We can pump into the holding tank normally, with zero issues. And, as we're in a marina, we've used only salt water to test the overboard discharge. Just wanted to put that out there.

What we have done thus far:

Replaced the flapper valve and spring assembly
Replaced the joker valve
Replaced the bowl gasket
Removed and cleaned all system hoses, removing all scale and deposits until the hose interiors are reflective and clean
Replaced the Y-Valve with a new unit
Cleaned the nipples/tailpieces on the intake and discharge through-hull fittings
Tested the through hull fittings for proper operation
Cleaned the vented loops and valves
Had a trusted diver inspect the intake and discharge through hull fittings from the outside, including reaming/probing for obstructions

Short of catching us up on maintenance, none of this changed anything. We still cannot pump overboard from the head without developing significant back pressure/resistance, and the bowl does not empty. We can pump into the holding tank normally, no issues whatsoever. We've also noticed the static water level in the bowl is now hogher than it has been normally. The only thing we haven't done is a complete rebuild of the pump, (remember, we can pump into the holding tank with no issues), and the pump was fully reconditioned/rebuilt by Groco in 2015. Patrick at Groco said we should expect 7-10 years of trouble free operation. This instantaneous development is most frustrating.

I'm calling Groco on Monday.

Any Pacific Seacraft 34 owners want to share info on composting heads??
Bill,

Do you still have the original PSC setup with the T-junction or did you replace that with a Y-valve (as you indicate above)? It seems to me that if there is no problem pumping into the holding tank, but pressure builds up when pumping overboard, there must be a blockage between the T-junction (or Y-valve) and the through hull. I would try to remove the hose from the pipe that leads to the through-hull and pump seawater into a bucket. That would tell you right away if that hose is blocked or if there is an issue with the through-hull.

Joost
 

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Discussion Starter #3
Bill,

Do you still have the original PSC setup with the T-junction or did you replace that with a Y-valve (as you indicate above)? It seems to me that if there is no problem pumping into the holding tank, but pressure builds up when pumping overboard, there must be a blockage between the T-junction (or Y-valve) and the through hull. I would try to remove the hose from the pipe that leads to the through-hull and pump seawater into a bucket. That would tell you right away if that hose is blocked or if there is an issue with the through-hull.

Joost
Joost -

Thank you for your reply. Yes, we have the T-junction set-up on the discharge side; we kept that set-up to have the option to manually discharge the holding tank while at sea. The Y-valve was replaced with a new valve yesterday, and all of the discharge lines - from the base of the toilet, to the Y, and to the T, were removed and cleaned completely...we could see through the hoses and see reflections on the interior hose walls. (The line to the holding tank was not scaled and was clear, oddly enough!) The T was not removed, but was cleaned and reamed in placed and flushed with seawater by opening and closing the seacock, which exhibited a full flow. The exterior sections of the through hulls were checked by a diver for obstructions with none found.

However, we did not try to pump the toilet with the discharge line removed from the T; we will give that a try in the next day or so.

Thanks!
 

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Joost -

Thank you for your reply. Yes, we have the T-junction set-up on the discharge side; we kept that set-up to have the option to manually discharge the holding tank while at sea. The Y-valve was replaced with a new valve yesterday, and all of the discharge lines - from the base of the toilet, to the Y, and to the T, were removed and cleaned completely...we could see through the hoses and see reflections on the interior hose walls. (The line to the holding tank was not scaled and was clear, oddly enough!) The T was not removed, but was cleaned and reamed in placed and flushed with seawater by opening and closing the seacock, which exhibited a full flow. The exterior sections of the through hulls were checked by a diver for obstructions with none found.

However, we did not try to pump the toilet with the discharge line removed from the T; we will give that a try in the next day or so.

Thanks!
Bill,

If you still have to original setup, then where is the Y-valve located? Mine (from 1995) didn't have one and I just replaced the T-junction with a Y-valve to be able to select overboard discharge or discharge to the holding tank without having any sewage remaining in the hoses.

I was thinking the blockage in your case was between the T-valve and the seacock. Is it possible that there is something in there that allows flow coming from the seacock, but not the other way around? Do let us know once you figure out what the problem is.

Good luck,
Joost
 

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Discussion Starter #5
Bill,

If you still have to original setup, then where is the Y-valve located? Mine (from 1995) didn't have one and I just replaced the T-junction with a Y-valve to be able to select overboard discharge or discharge to the holding tank without having any sewage remaining in the hoses.

I was thinking the blockage in your case was between the T-valve and the seacock. Is it possible that there is something in there that allows flow coming from the seacock, but not the other way around? Do let us know once you figure out what the problem is.

Good luck,
Joost
Joost -

Hmmm, then we must not have the original set-up on the system. The T fitting which I referred to is fitted on top of the discharge seacock, 'downstream' from the Y-valve.

The system flows as follows: waste/water empty out of the the bowl, pass through a siphon-break loop, and into the Y-valve. If we're discharging overboard, the Y is directed to the discharge seacock through one side of the T and overboard. If we're pumping into the holding tank, then the Y is selected to divert the flow into the tank inlet hose.

We can pump the holding tank overboard manually when at sea. When we do this, we set the Y to flow into the overboard hose, thereby isolating the holding tank, and open a separate ball valve which will allow the contents of the holding tank to drain. It is this hose from the holding tank, which is connected to the other end of the T fitting on the discharge seacock. We can then use the Gusher pump to discharge the holding tank. As far as I'm aware, there is no check-valve in the T. We've not used this system since out last offshore passage which was around 2.5 years ago.
 

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Joost -

Hmmm, then we must not have the original set-up on the system. The T fitting which I referred to is fitted on top of the discharge seacock, 'downstream' from the Y-valve.

The system flows as follows: waste/water empty out of the the bowl, pass through a siphon-break loop, and into the Y-valve. If we're discharging overboard, the Y is directed to the discharge seacock through one side of the T and overboard. If we're pumping into the holding tank, then the Y is selected to divert the flow into the tank inlet hose.

We can pump the holding tank overboard manually when at sea. When we do this, we set the Y to flow into the overboard hose, thereby isolating the holding tank, and open a separate ball valve which will allow the contents of the holding tank to drain. It is this hose from the holding tank, which is connected to the other end of the T fitting on the discharge seacock. We can then use the Gusher pump to discharge the holding tank. As far as I'm aware, there is no check-valve in the T. We've not used this system since out last offshore passage which was around 2.5 years ago.
Bill,

In my system the waste water goes to a T-fitting first where I can select the holding tank or overboard discharge by closing a valve downstream between the T and the holding tank. Not ideal as that means there is always waste water in the overboard discharge. I recently replaced that T with a Y-valve and now my system is similar to yours.

If you remove the hose from the T fitting and pump into a bucket, you can isolate the problem to either the T or an upstream blockage. I'm inclined to believe that there is something stuck in the T fitting that allows easy flow in one direction but not the other. Best of luck!

Joost
 

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Discussion Starter #7
UPDATE

So...a comedy of errors...sort of. :unsure: For the backstory, please see my OP, above.

First things first: Groco customer service was superb as it always has been. I had a lengthy conversation with Patrick and also received a follow-up call from Steve this afternoon. It was Patrick who convinced me to go back and re-examine the new Y-Valve. "Whatever the problem is, and I'm convinced it's a blockage, is at that Y," he said.

In short, I installed the Y-Valve incorrectly, based on where I remembered the orientation of the hose barbs to be. This put the barbs for the inlet to the Y from the toilet in the wrong spot, which conversely put the discharge overboard barbs in the wrong spot. The holding tank barbs wound up in the correct spot. So, in quite the coincidence, I inadvertently created the same problem in my repair, which I was trying to fix. :rolleyes:

The Y valve is reoriented and the toilet is functioning normally once again.

Thanks again to all who replied and gave input - and big kudos to Groco! (y)
 
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Glad that problem got resolved. The question is, what caused the sudden blockage before you replaced the Y-valve?

I just installed a Y-valve, I'd better go back and make sure I didn't make the same mistake...
 

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Discussion Starter #9
Glad that problem got resolved. The question is, what caused the sudden blockage before you replaced the Y-valve?

I just installed a Y-valve, I'd better go back and make sure I didn't make the same mistake...
We are glad it's resolved as well!

I'm presuming the original issue was simply some scale/calcification which broke away and jammed somewhere in the discharge hose. The old Y was quite heavily scaled as were the hoses downstream from it; the hoses from the toilet outlet to the siphon break, and the siphon break to the Y had some scale but to a lesser degree. In both cases, the problem was a simple blockage in the hose...only I directly and instantly created the latter one!
 

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By the way, Bill, do you have any recommendations/tricks for replacing the joker valve - I've done it a few times, but always wind up taking a bunch of things apart. Is there a way of doing it that doesn't require taking the elbow off the head?
 

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Discussion Starter #11 (Edited)
By the way, Bill, do you have any recommendations/tricks for replacing the joker valve - I've done it a few times, but always wind up taking a bunch of things apart. Is there a way of doing it that doesn't require taking the elbow off the head?
I wish I did. I've not had to remove the elbow from the pump, but do have to remove the bowl. I've tried it without taking off the bowl, and it hasn't worked for me.

One thing we did a long time ago, which greatly extended the life of our joker valve, was to strictly prohibit anything going into the bowl which had not passed through the human digestive tract. No toilet paper, not even the stuff designed for use in marine/RV systems; nothing but solid and/or liquid human waste. The TP gets placed in a zip-lock bag and disposed of with the ship's trash. It made a big difference.
 

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I wish I did. I've not had to remove the elbow from the pump, but do have to remove the bowl. I've tried it without taking off the bowl, and it hasn't worked for me.

One thing we did a long time ago, which greatly extended the life of our joker valve, was to strictly prohibit anything going into the bowl which had not passed through the human digestive tract. No toilet paper, not even the stuff designed for use in marine/RV systems; nothing but solid and/or liquid human waste. The TP gets placed in a zip-lock bag and disposed of with the ship's trash. It made a big difference.
Thanks, Bill. That's what we do also. We only use the boat during the New England sailing season, so the joker valve doesn't have to be replaced all that often, but still it's not the most pleasant job.

I find removing the bowl quite difficult. I can easily reach the bolts, but the last one is always a pain. Maybe I'll try to do it your way next time.
 

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Discussion Starter #14
Thanks, Bill. That's what we do also. We only use the boat during the New England sailing season, so the joker valve doesn't have to be replaced all that often, but still it's not the most pleasant job.

I find removing the bowl quite difficult. I can easily reach the bolts, but the last one is always a pain. Maybe I'll try to do it your way next time.
We live aboard full-time, so ours is replaced at least once per year.

Removing the bowl can definitely be a challenge, especially the back bolt on the left. (When facing the bowl.) I need to replace all of the bolts for the bowl/pump attachment and the joker valve housing. They work, but over the years, they've become quite a mixed collection.
 
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I took the head home over the winter and completely took it apart, replaced all the rubber parts, repainted the metal. Now it works a charm.
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