Toilet backing up

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nimrod1230

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Oh dear, another question in quick succession. The penalty for having a new/secondhand boat to explore. The head is back filling with water if i'm lucky or something nasty if not very thoroughly flushed through. This is my first experience of a holding tank which drains overboard by gravity if so directed. I can pump the toilet dry untill I can hear no more water falling into the tank and half an hour later the bowl is quarter full again. When handing over the boat I asked the agents engineer if a new joker valve was needed to be told there is none fitted and that this is a Jeanneau trait! True or false from your extensive knowledge base?
 
I had the great misfortunte to experience recently my first on-board toilet problems in decades of cruising, the resolution of which occupied a surprisingly great proportion of my August cruise. So I have acquired some modest knowledge of the black arts, so to speak, of boat plumbing, which I will try to share with you.

That part of your black water system which prevents back flow into the toilet is indeed the joker valve, as you correctly guessed, and nothing else. So that element of your system is what you should concentrate on first, in diagnosing your problem. It could hardly be anything else.

The joker valve can stop doing its job in case it is clogged a little with some foreign material like hair or paper products. Or it can be sedimented up.

As an aside, you may or may not be aware of the fact that sea water plus pee produces intense calcium sedimentation. Whether or not this is the source of your problem, you should flush your toilet with Harpic and fresh water at the end of every cruise, then flush out the Harpic with more fresh water, before shutting off the sea cocks. This will keep that sediment at bay, that plus enough pump strokes after every use of the toilet.

So I would suggest that you start by taking apart the manifold on your toilet where the pump is connected to your plumbing. You will find the joker valve there. Clean it, and examine it. If it's not cracked or distorted, then just give it a good clean and reinstall it. Mosty likely, that will solve your problem.
 
Thanks Dockhead. You didn't pick up on the comment " none fitted" with regard to the joker valve? I am under the impression that a pump toilet would not function without one?
 
nimrod1230 said:
Thanks Dockhead. You didn't pick up on the comment " none fitted" with regard to the joker valve? I am under the impression that a pump toilet would not function without one?
Click to expand...

You are correct. There's a joker valve in there somewhere.
 
nimrod1230 said:
Oh dear, another question in quick succession. The penalty for having a new/secondhand boat to explore. The head is back filling with water if i'm lucky or something nasty if not very thoroughly flushed through. This is my first experience of a holding tank which drains overboard by gravity if so directed. I can pump the toilet dry untill I can hear no more water falling into the tank and half an hour later the bowl is quarter full again. When handing over the boat I asked the agents engineer if a new joker valve was needed to be told there is none fitted and that this is a Jeanneau trait! True or false from your extensive knowledge base?
Click to expand...


I would suggest you familiarise yourself with the pipe layout of this system as you may need to answer questions to ensure your problems are sorted.

The fact you have a gravity tank should have no bearing on this problem. The discharge from the toilet pump probably goes to the top of the holding tank . What you are seeing is the content of the hose between the pump and tank running back. The pump discharge valve should prevent this however if it has calcified deposits on it or it is damaged then it may allow slow leakage till the HOSE empties. If there is a place in the loo body for an additional joer valve then it might help belt and braces style however the pump delivery valve should do the job and probably uses a similar rubber insert.
 
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I would suspect there's a joker valve in there too. If not, maybe you could get the Agent's Engineer to say what is there instead.

It sounds like your holding tank is similar to mine. The joker valve holds the contents in place. Trouble is if you're filling the holding tank you can't flush through, so you get calcium build-up on the valve much quicker than you would without the holding tank, which makes the valve less flexible and more prone to leaking.

Replace the joker valve (or budget option try de-scaling it). What I've started doing is to leave the outlet sea cock of the holding tank open except when I really need the holding tank to hold stuff. That way you can fill the pipe above the joker valve with fresh sea water. So far so good.
 
dt4134 said:
Replace the joker valve (or budget option try de-scaling it).
Click to expand...

In yacht maintenance, and especially with toilets, try the easiest option first. In this case that is to dose the toilet with hydrochloric acid. Your symptoms suggest that the valve is encrusted with calcium scale that holds the lips of the seal open. It happens regularly on a well-used toilet. Tip some HCl in, let it sit there until it stops bubbling, pump two or three times, wait again. Keep doing this until you have used about a litre of HCl, then flush through with water. HCl is available as either brick acid or brick cleaner, the brick acid being the more concentrated form IIRC.

If that doesn't fix it you may have to resort to taking it apart.
 
You don't say what sort of loo you have. If it is a Lavac, I would say that the problem certainly lies with the outlet joker valve which can be checked by unscrewing the inspection plate on the front of the pump ( have a container ready to catch the contents). You can then check the valve for any obstructions and feel for any encrustations etc. If the condition of the valve feels a bit iffy, I would replace it. This can be done without dismantling the pump. If there are signs of serious encrustation, I would advise removing and dismantling the pump and cleaning thoroughly and replacing both valves. Any diverters in the system should be overhauled at the same time.

If it a Jabsco type , I reckon the problem may lie in the same area - as has been said -- disconnect the manifold and clean out or replace the valve.

I would always advocate replacement, otherwise the problem may well reappear. However, I am not aware of anyone who sells these things as single units. You usally have to buy a complete overhaul kit -- which in the case of the Lavac ( Henderson) is around £25 and you are left with lots of parts you don't need
 
vyv_cox said:
In yacht maintenance, and especially with toilets, try the easiest option first. In this case that is to dose the toilet with hydrochloric acid. Your symptoms suggest that the valve is encrusted with calcium scale that holds the lips of the seal open. It happens regularly on a well-used toilet. Tip some HCl in, let it sit there until it stops bubbling, pump two or three times, wait again. Keep doing this until you have used about a litre of HCl, then flush through with water. HCl is available as either brick acid or brick cleaner, the brick acid being the more concentrated form IIRC.

If that doesn't fix it you may have to resort to taking it apart.
Click to expand...

What are the risks of using HCl in the heads? Does it damage the rubber of the seals & joker valve? Would it damage the s/s holding tank?
 
dt4134 said:
What are the risks of using HCl in the heads? Does it damage the rubber of the seals & joker valve? Would it damage the s/s holding tank?
Click to expand...

The risk is very small indeed. The seals and valves used in toilets can be harmed by long-term exposure to concentrated HCl but not by the short-term exposure that we are talking about here. Nitrile and neoprene seals, which I believe are used in most toilets, are not affected by dilute HCl. As soon as the HCl comes into contact with the calcium salts it is being neutralised by the reaction, so is only active for a very short time. This also takes care of any environmental concerns - acid is not being pumped into the sea.

So far as the tank is concerned the chlorides in dilute HCl will affect a s/s tank, but barely more than the seawater will. Again, by the time it hits the tank it will almost certainly have reacted anyway, so minimal risk.
 
Also check that the breather pipe is clear I had a similar problem and found someone had rerouted the breather, this caused the tank to pressurise and prevented it filling properly.
 
vyv_cox said:
In yacht maintenance, and especially with toilets, try the easiest option first. In this case that is to dose the toilet with hydrochloric acid. Your symptoms suggest that the valve is encrusted with calcium scale that holds the lips of the seal open. It happens regularly on a well-used toilet. Tip some HCl in, let it sit there until it stops bubbling, pump two or three times, wait again. Keep doing this until you have used about a litre of HCl, then flush through with water. HCl is available as either brick acid or brick cleaner, the brick acid being the more concentrated form IIRC.

If that doesn't fix it you may have to resort to taking it apart.
Click to expand...


This will do it however it will upset things in the holding tank so a very good flushing of the tank afterwards :D
 
vyv_cox said:
The risk is very small indeed. The seals and valves used in toilets can be harmed by long-term exposure to concentrated HCl but not by the short-term exposure that we are talking about here. Nitrile and neoprene seals, which I believe are used in most toilets, are not affected by dilute HCl. As soon as the HCl comes into contact with the calcium salts it is being neutralised by the reaction, so is only active for a very short time. This also takes care of any environmental concerns - acid is not being pumped into the sea.

So far as the tank is concerned the chlorides in dilute HCl will affect a s/s tank, but barely more than the seawater will. Again, by the time it hits the tank it will almost certainly have reacted anyway, so minimal risk.
Click to expand...

Thanks.
 
samwise said:
If it a Jabsco type , I reckon the problem may lie in the same area - as has been said -- disconnect the manifold and clean out or replace the valve.

I would always advocate replacement, otherwise the problem may well reappear. However, I am not aware of anyone who sells these things as single units. You usally have to buy a complete overhaul kit -- which in the case of the Lavac ( Henderson) is around £25 and you are left with lots of parts you don't need
Click to expand...

Joker valves for Jabsco are available separately. Just bought one, Jabsco part no 29092 - 1000 covers all models 1986 on Price £5.19 Bargain in today's world.
 
joker valve

well not much of a joker. I went for the clean the valve option and took the pipe off where the pump meets the pipe. There was a bit of back pressure and then syphoning action which i didn't have the means to stop, so very fast cleaning took place in a very small and smelly heads. The valve was completly coated in scale, even though it's only 2 years old. Thats cured the backup. Go for cleaning valve option, i'm sure it's better then messing around with acid.
 
geoff9959 said:
Go for cleaning valve option, i'm sure it's better then messing around with acid.
Click to expand...

Suit yourself. This is my way: Tip a bottle into the toilet, wait a couple of minutes, pump, wait a couple of minutes, then flush through. Total time ten minutes.

Your way: struggle to undo the fitting that houses the joker valve, inevitably involving kneeling over the toilet trying to fit spanner and screwdriver to the fitting, releasing a hose full of sewage which is impossible to catch in any receptacle, some of which will land on your feet and the rest run somewhere into the boat. Then extract the joker valve, clean the filthy and disgusting housing and reassemble. Clean up and disinfect your feet and the other places to which the sewage has run. Total time 30 - 60 minutes, depending how it goes. ;)
 
Well I did change the joker valve which I managed to buy on it's own. The old one was a bit crusty but not too bad and the pipe pretty much ok. Problem solved though I think a regular dose of HCI will now be on the monthly to do list. Thanks everyone as ever.
 
vyv_cox said:
Suit yourself. This is my way: Tip a bottle into the toilet, wait a couple of minutes, pump, wait a couple of minutes, then flush through. Total time ten minutes.

Your way: struggle to undo the fitting that houses the joker valve, inevitably involving kneeling over the toilet trying to fit spanner and screwdriver to the fitting, releasing a hose full of sewage which is impossible to catch in any receptacle, some of which will land on your feet and the rest run somewhere into the boat. Then extract the joker valve, clean the filthy and disgusting housing and reassemble. Clean up and disinfect your feet and the other places to which the sewage has run. Total time 30 - 60 minutes, depending how it goes. ;)
Click to expand...

well now let me see s**t on me shoes or leaks all over the boat from burntout pipes.....um.
 
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