OCC Forums

Blocked Heads - Thread on Facebook initiated by Bob Carlisle...

https://forum.oceancruisingclub.org/Topic5120.aspx

By bbalme - 28 May 2019

A morning of ‘wishing I’d thought about that a bit earlier’:
Having been disturbed from my book by Lesley’s call that: ‘The head’s pump has jammed solid’ – she was the one using it, so why is that my problem? – I happily laid my book aside for the joyous alternative of playing around with some pressurised turds.
As a recent convert to the idea of illuminating such tasks with a torch that ‘fits comfortably into your mouth’ rather than head-torches (thanks Tony Goode off ‘S/Y Capische’) I’d inserted/removed said torch at least half-dozen times before getting around to contemplating what my hands were doing in between.
Having discovered that the three-way valves and 38mm outlet hose had scaled-up to perhaps 12mm diameter, Lesley pointed out that it was ‘better to discover that now rather than half way to Tonga’. I immediately recalled Lesley having said almost precisely the same thing with regard to these hoses and our passage to the Marquesas; that had been back in Panama over a year ago, no wonder they were chocked-solid!
Having stripped out all the hoses, vigorously beaten them over the side to clear out the calcite deposits and begun the reassembly process, I recalled that on all previous occasions that I’ve pulled the long hose to the outlet seacock out from beneath the floor, I’ve first taped a draw-cord/mousing-line onto the end of it. I now know that you can re-thread it without one, provided of course that you fancy an extra hour or so of wallowing around in sewage.
Having eventually got all re-assembled, working perfectly and with no leaking valves/pumps/joints (first try - a miracle!) I was at that point that anyone whose done the job themselves will appreciate; that wonderful moment when you can leap over the side and freshen-up, before re-boarding to take a very soapy shower. That was exactly the moment when I recalled what the surgical nurse at Raiatea hospital had told me just yesterday about my leg wound: ‘You can shower as normal, but don't risk infection by going into the sea until the stitches have dissolved in 3-4 weeks’ time”.
Perhaps I should just be grateful that the nurse hadn’t put any prohibition on fixing the heads, or suggested that there might be any infection risk from playing around in raw sewage?


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Reg Barker Bob, we got a top tip from a very experience round the world OCC sailing couple when we were in the Med. There's something about the seawater in the Med that seems to scale up the pipes in superquick time and, as always with yachts, the after dinner conversation migrated to maintenace challenges. Their top tip was to regulalry descale the heads pipework with ordinary vinegar. We did a quick schoolboy calculation on the volume of our outflow pipe and initially just pumped that amount of vinegar through and then shut off the outlet valve. We left that overnight or even for 24 hrs. It's been amazing; we haven't removed or banged a 38mm outlet hose in 5 years. Our latest improvement to the procedure is to pump like billyho to fill the outlet pipe with air and, as a double act, as the last pump is made the skin fitting valve is closed. We the loosen the air bleed valve on the top of the swan neck and GENTLY pump in the vinegar though the bowl until the pipes are full and small amount bleeds out onto a tissue. With this method the vinegar now completely fills the pipe on both sides of the swan neck including covering our selector valve to the holding tank. That now turns easily always which it didn't always with the old method. As a final addition, Nicky did a calculation on how many pumps it takes to completely flush our long outflow pipe run (28 pumps!!!) and since we then have been pumping that much per flush (when pumping to sea) and have noticed an improvement in slower scaling up. Hope our suggestions prevent a rerun of your recent trauma.

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John Sweeney I had a blockage (the heads that is 🤣) crossing outer biscay from Ireland last summer. After spending sometime upside down and contorted in the heads areas, a yachtmans handbook in one hand and a variety of implements in the other (including a wire coat hanger and various parts of the heads), we decided that the blockage was external. One of my crew, an experienced diver, donned the snorkel and mask, armed himself with the coat hanger, and within minutes the blockage was freed!! Too much loo role....no blame apportioned, but I may have been the last user! However, the material that came out was calcified too. Since then we use a sealed plastic bag, and contents disgarded at an appropriate land bin. Now nothing goes overboard, only the fishing line 😇😎


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Neil McCubbin We periodically flush hydrochloride acid ( aka muriatic acid) through, leaving it in the system overnight
Seems to avoid scale
It is sold for cleaning concrete and other stuff, but is hard to find in some countries

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Linda Lane Thornton I bought some of that when we were in the US, Neil McCubbin, but the instructions and the warnings were dire - so I went back to vinegar instead.

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Neil McCubbin Agreed that care is required. It is used a lot in industry, and is much more aggressive to head scale than vinegar.

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Gus Wilson Neil McCubbinI I agree re the muriatic acid. IT takes a long time for household vinegar to work. HCl does not seem to bother plastic or synthetic rubber very much. The 30% or so vinegar sold in Denmark, in with cleaning products, will bubble away a lot too.


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Phil Heaton I have not found vinegar very effective - maybe not using enough often enough - but agree re Muriatic acid but what % dilution/concentration do you use? Recently had to clear all the hose in both heads. Norma watched but reported that I was "heroic" - that made it all worthwhile....

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Neil McCubbin About 3%
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John Franklin The real solution is to prevent the pipework scaling up rather than trying to remove the scale. Scale is formed by the reaction between urine and seawater, so flush the heads very thoroughly after each use to ensure complete removal of urine from the pipework. Most heads manufacturers quote the number of pumps to clear each metre of pipe. Aboard Al Shaheen we pumped 20 times and never had a scaling problem in 15 years.

-----------
Neil McCubbin John Franklin We do same, but cannot when marinas or small anchorages for longer than the one day or so that our holding tank is good for when pumping a lot
 

By Dick - 29 May 2019

Bill Balme - 5/28/2019
A morning of ‘wishing I’d thought about that a bit earlier’:
Having been disturbed from my book by Lesley’s call that: ‘The head’s pump has jammed solid’ – she was the one using it, so why is that my problem? – I happily laid my book aside for the joyous alternative of playing around with some pressurised turds.
As a recent convert to the idea of illuminating such tasks with a torch that ‘fits comfortably into your mouth’ rather than head-torches (thanks Tony Goode off ‘S/Y Capische’) I’d inserted/removed said torch at least half-dozen times before getting around to contemplating what my hands were doing in between.
Having discovered that the three-way valves and 38mm outlet hose had scaled-up to perhaps 12mm diameter, Lesley pointed out that it was ‘better to discover that now rather than half way to Tonga’. I immediately recalled Lesley having said almost precisely the same thing with regard to these hoses and our passage to the Marquesas; that had been back in Panama over a year ago, no wonder they were chocked-solid!
Having stripped out all the hoses, vigorously beaten them over the side to clear out the calcite deposits and begun the reassembly process, I recalled that on all previous occasions that I’ve pulled the long hose to the outlet seacock out from beneath the floor, I’ve first taped a draw-cord/mousing-line onto the end of it. I now know that you can re-thread it without one, provided of course that you fancy an extra hour or so of wallowing around in sewage.
Having eventually got all re-assembled, working perfectly and with no leaking valves/pumps/joints (first try - a miracle!) I was at that point that anyone whose done the job themselves will appreciate; that wonderful moment when you can leap over the side and freshen-up, before re-boarding to take a very soapy shower. That was exactly the moment when I recalled what the surgical nurse at Raiatea hospital had told me just yesterday about my leg wound: ‘You can shower as normal, but don't risk infection by going into the sea until the stitches have dissolved in 3-4 weeks’ time”.
Perhaps I should just be grateful that the nurse hadn’t put any prohibition on fixing the heads, or suggested that there might be any infection risk from playing around in raw sewage?


--------
Reg Barker Bob, we got a top tip from a very experience round the world OCC sailing couple when we were in the Med. There's something about the seawater in the Med that seems to scale up the pipes in superquick time and, as always with yachts, the after dinner conversation migrated to maintenace challenges. Their top tip was to regulalry descale the heads pipework with ordinary vinegar. We did a quick schoolboy calculation on the volume of our outflow pipe and initially just pumped that amount of vinegar through and then shut off the outlet valve. We left that overnight or even for 24 hrs. It's been amazing; we haven't removed or banged a 38mm outlet hose in 5 years. Our latest improvement to the procedure is to pump like billyho to fill the outlet pipe with air and, as a double act, as the last pump is made the skin fitting valve is closed. We the loosen the air bleed valve on the top of the swan neck and GENTLY pump in the vinegar though the bowl until the pipes are full and small amount bleeds out onto a tissue. With this method the vinegar now completely fills the pipe on both sides of the swan neck including covering our selector valve to the holding tank. That now turns easily always which it didn't always with the old method. As a final addition, Nicky did a calculation on how many pumps it takes to completely flush our long outflow pipe run (28 pumps!!!) and since we then have been pumping that much per flush (when pumping to sea) and have noticed an improvement in slower scaling up. Hope our suggestions prevent a rerun of your recent trauma.

----------
John Sweeney I had a blockage (the heads that is 🤣) crossing outer biscay from Ireland last summer. After spending sometime upside down and contorted in the heads areas, a yachtmans handbook in one hand and a variety of implements in the other (including a wire coat hanger and various parts of the heads), we decided that the blockage was external. One of my crew, an experienced diver, donned the snorkel and mask, armed himself with the coat hanger, and within minutes the blockage was freed!! Too much loo role....no blame apportioned, but I may have been the last user! However, the material that came out was calcified too. Since then we use a sealed plastic bag, and contents disgarded at an appropriate land bin. Now nothing goes overboard, only the fishing line 😇😎


------------
Neil McCubbin We periodically flush hydrochloride acid ( aka muriatic acid) through, leaving it in the system overnight
Seems to avoid scale
It is sold for cleaning concrete and other stuff, but is hard to find in some countries

---------
Linda Lane Thornton I bought some of that when we were in the US, Neil McCubbin, but the instructions and the warnings were dire - so I went back to vinegar instead.

--------
Neil McCubbin Agreed that care is required. It is used a lot in industry, and is much more aggressive to head scale than vinegar.

---------
Gus Wilson Neil McCubbinI I agree re the muriatic acid. IT takes a long time for household vinegar to work. HCl does not seem to bother plastic or synthetic rubber very much. The 30% or so vinegar sold in Denmark, in with cleaning products, will bubble away a lot too.


----------
Phil Heaton I have not found vinegar very effective - maybe not using enough often enough - but agree re Muriatic acid but what % dilution/concentration do you use? Recently had to clear all the hose in both heads. Norma watched but reported that I was "heroic" - that made it all worthwhile....

----------
Neil McCubbin About 3%
-----------
John Franklin The real solution is to prevent the pipework scaling up rather than trying to remove the scale. Scale is formed by the reaction between urine and seawater, so flush the heads very thoroughly after each use to ensure complete removal of urine from the pipework. Most heads manufacturers quote the number of pumps to clear each metre of pipe. Aboard Al Shaheen we pumped 20 times and never had a scaling problem in 15 years.

-----------
Neil McCubbin John Franklin We do same, but cannot when marinas or small anchorages for longer than the one day or so that our holding tank is good for when pumping a lot
 


A sanitation hose suggestion:
Dick Stevenson, s/v Alchemy
There are lots of methods for avoiding the sanitation hose blockage: some are common sense: pump a lot, while others take varying methods of effort (soaking in vinegar) or courage/nerve (muriatic acid). All have adherents, but none seems to have risen to the level of “solution” or “best practices”.
With the idea that fooling with the sanitation hose every now and again is inevitable: the following made sense to me and we have executed this a couple of times already.
A few initial notes:
1.    A powerful heat gun (a hair drier will help in a pinch) is a huge help at dealing with any removal or installation of hose (any plumbing hose actually, not just sanitation hose). It also contributes to the hose “setting” around the barb when tightening hose clamps.
2.    Lightweight disposable aluminum “meatloaf” pans in various shapes are a huge mess mitigator. Find ways to shape them under connections to catch the always yucky (technical term) water/sludge that is bound to emerge. Be patient with the drips. Cleaning the pans is made easy with a vacuum hand pump/container such as many of us use to change our oil.
3.    A little swipe of dishwashing detergent goes a long way to helping get hoses onto barbed connections and quickly washes away.
I have switched my thinking over the past 10+ years. After decades of buying the best sanitation hose: the kind that is basically built like multi-ply steel-belted radial tires with wire spiral reinforcement, I have gone to what I think of as the “cheap stuff”: solid white rubber hose with no wire reinforcement. The difference in price is impressive and the flexibility/ease of handling difference is equally astounding. We have found that there have been no smell differences between the two types, a big selling point in the advertising of the expensive hose.
What we do is swap the hose on schedule before there is a problem. (We re-build the toilet at the same time.) Doing the job on schedule allows us to do the job in the most convenient position: usually on the hard with access to other sanitation facilities, fresh water, and power for the heat gun and no urgency. Measuring and recording each hose run carefully the first time allows you to cut new sections ahead of time, again easing further installations.
Removal is a doddle. Flush with lots of fresh water before proceeding. At the low connection points, use disposable aluminum baking pans and mold them to catch drips/puddles (like under the joker valve): duct tape can be used to direct and secure the pan/drips and be patient. Without the wire spiral, cut chunks out of the hose anywhere, remove hose clamps, heat at the connections and pull free. If there is a vented loop, ensure it is not clogged: especially the “vent” part of the vented loop.
Installation is easy and quick. Not being wire reinforced nor being multi-ply, cutting is easy with simple sheers or a stiff sharp knife: hack saw works well also. Use a heat gun to heat the whole run and wiggling the hose most anywhere is a doddle as it acts (a bit) like a noodle. This hose is not wire reinforced so avoid sharp turns: finding routing with wide curves is usually not a problem (our old wire reinforced hose did not bend sharply so the previous route was fine). When warm, one can get the hose between 2 fixed points without too much wrestling, unlike the wire re-enforced hose, and allows installation without removal of divert valves, vented loops etc. As the hose cools, it takes on a set and stiffens up considerably.
The next go-around of replacement, you have exact measurements which makes the installation go quickly. I thought I would need to redo in 2-3 years of full time live aboard, but I was surprised that at 4 years, I did not need to replace every hose section. There was no smell or problem. It may help to have been live aboard and have a lot of action through the hoses rather that their sitting for periods with salt water + deposits in them. We also make a habit of pumping thoroughly. The last 3-4 years of 6-months-on/6-months-off the boat has not seen any smell permeating also. Interestingly, I have found roughly the same amount of build up closing up the hose as when living aboard.
Not dealing with wire reinforced hose is a pleasure! And saves money on band-aids.
Come back with questions/comments.
My best, Dick Stevenson, s/v Alchemy
By Tom.Ray - 21 Jan 2024

Realize this is an old thread but will weigh in nevertheless. How we have avoided having blocked heads (had to change the discharge hose once and was enough!) is two fold. First we use fresh water for flushing. A luxury enabled by having a water maker. The second reason is that we have NO toilet paper aboard. I installed a Tushy (brand) bidet. I had to tap into a fresh water line. No electricity is required. It works great. Selling my wife on the idea was easy. Told her if you take grape jelly and spread it on your arm and then wipe it with a paper towel, what do you get?

She had me install them in the house.

Another benefit is that our black water tank tenders work reasonably well. I can actually get a good idea of how full they are.

Tushy bidet….thats the ticket.

Tom
S/V Lyric