Jabsco manual toilet bowl doesn't empty

dtfmw

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We're very new yacht owners, and are having trouble working out why our Jabsco manual toilet (Model 29090-2000) bowl won't empty. We've installed everything in the service kit (piston O-ring, bottom valve gasket, joker valve) and after this it did empty perfectly a couple of times, but now the water refuses to budge again. The handle is easy to push and pull - in fact when it's moved you can hear water sloshing, although the water in the bowl doesn't move. We've checked the waste tank is empty, and the waste tank vent isn't blocked. What's the next step? How do we investigate whether there is a blockage in the outlet (waste) hose? It's pretty inaccessible on the boat. Any advice would be greatly appreciated.
 

CPD

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It is quite possible the joker valve has inverted which would give the sypmtoms you describe. I think it is only 2 screws you need to undo to get at it .....
 

dtfmw

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The seacock is open to the holding tank, which is empty. I took the toilet apart again earlier - the (new) joker valve had inverted, so I turned it right way out, reinstalled it, put the toilet back together again, it flushed once then same problem. The joker valve has inverted again. Does this mean a block somewhere between the toilet and the waste tank? There's no blockage in the discharge elbow and about a foot beyond - that's as far as the equipment I've got will let me reach!
 

vyv_cox

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I think the base valve has been installed the wrong way up. When the piston is drawn up the valve should open to draw water out of the bowl, then when the piston goes down this valve closes and the joker valve opens. In your case when you draw the piston up the base valve is closed so the joker valve tries to open but can't so it inverts. The base valve opens when you push the piston down, accounting for the sounds you hear.
 

dtfmw

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As far as I can work out, I've got the base valve gasket on the right way up as it has 3 holes in the edges that correspond to 3 plastic bits on the base. The fat bit of the gasket is facing upwards. I don't think it would fit the other way, but I'm willing to give it a go if you think it will do the trick!
Thanks for all the responses so far, btw.
 

dtfmw

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I think so. The joker valve is sitting in the hose to the discharge elbow, with the rim of the valve level with the rim of the hose. That is until it inverts!
 

vyv_cox

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As far as I can work out, I've got the base valve gasket on the right way up as it has 3 holes in the edges that correspond to 3 plastic bits on the base. The fat bit of the gasket is facing upwards. I don't think it would fit the other way, but I'm willing to give it a go if you think it will do the trick!
Thanks for all the responses so far, btw.

That sounds right but maybe it's sticking or something similar. It should lift up and sit down closed.

You could assess whether you have a blockage by deliberately causing one - close the seacock and block off the holding tank vent with a wooden bung. Don't pump too vigorously as you might burst something but you should be able to tell if it makes a difference.
 

Martin_J

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When my joker valve had a few inversions, it was when the outlet pipe was seriously blocked.

By pushing hard down on the plunger some waste water was forced through the joker valve into the outet hose. When I let go of the handle it came back up all by itself under the pressure of the waste water returning the wrong way through the joker valve - and hence inverting it.

Is your pump handle hard to push down and then it tends to pop up by itself?
 
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Stork_III

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If the joker valve is inverting, it is inverting due to downstream back pressure, either seacock shut, or blockage in pipe to seacock or holding tank, or tank vent blocked.
 

dtfmw

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I'm not sure my investigations can go any further, as in taking apart and reattaching the pump cylinder and the base several times, it now appears the thread for one of the four screws inside the base has disintegrated, so the connection can't be secured. Also there is a hairline crack towards the bottom of the pump cylinder. I'm thinking it might just be easier to get a new toilet and discharge hose. Any recommendations as to a new Jabsco or a better alternative?
 

Stork_III

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I'm not sure my investigations can go any further, as in taking apart and reattaching the pump cylinder and the base several times, it now appears the thread for one of the four screws inside the base has disintegrated, so the connection can't be secured. Also there is a hairline crack towards the bottom of the pump cylinder. I'm thinking it might just be easier to get a new toilet and discharge hose. Any recommendations as to a new Jabsco or a better alternative?
It is possible to buy a new base mounting and Pump (latest lock down version) but will cost nearly as much a a new complete toilet. A replacement Jabsco will fit straight in, any other will involve varying degrees of fiddle and hassle to get pipe runs to fit etc, as well as greater cost, much greater in some makes. I have only ever had Jabsco so can't recommend alternative. The blockage will need fixing.
 

VicS

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A link to the "Jabscoshop" might be useful.

http://www.jabscoshop.com/marine/marine-toilets/toilets/manual-toilets/

Click on your toilet to get a parts diagram, which you can zoom to read more clearly, and parts list giving details of service kits and separately available parts together with prices.

If it really does come to replacing the whole toilet then replace it with a Lavac if you can fit and plumb one in exactly as per the instructions

See http://www.blakes-lavac-taylors.co.uk/prod03.htm.

If you fit a Lavac and follow the installation instructions carefully you will be able to say good bye to toilet problems
 

VicS

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Only problem with Lavac is the price £234!!!!!!!!!!!

Should be able to get one for under £200. ( complete with pump)

But the choice is simple .
A Lavac that will work for decades with no more than occasional overhaul of the pump ( which is no more than a white version of a standard bilge pump) or a Jabsco that will always be troublesome and regularly require the purchase of expensive spares if not total replacement at intervals.
 

Kilter

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Should be able to get one for under £200. ( complete with pump)

But the choice is simple .
A Lavac that will work for decades with no more than occasional overhaul of the pump ( which is no more than a white version of a standard bilge pump) or a Jabsco that will always be troublesome and regularly require the purchase of expensive spares if not total replacement at intervals.

+1
 
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