Jabsco toilet

[Roberto]

I have a problem with a manual jabsco toilet : the sea water intake side of the pump seems not to be working.

I opened the whole thing (how can it be it did not smell at all?) under the pump handle, replaced the broken o-ring of the pump piston, cleaned the upper rectangular rubber membrane with the small openings, lightly greased everything, etc etc. There seems to be no air leak around the rubber membrane when the six screws are tight.

With the lever in the flush position, the pump is unable to draw sea water, not even a single drop. The sea water intake hose and seacock have been cleaned and water passes freely. I tried priming the pump by taking off the intake hose from the seacock and plunging it into a bucket of water above, but to no avail.

I poured half a bucket of water in the bowl and the pump evacuated it with no difficulties. (That s how we ended up using the toilet).

Any ideas?


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[Jacket]

This isn't a very technical answer, but I've had this problem in the past, and the solution was to remove the top of the pump, take out the rubber membrane, put it back in place and screw the top of the pump back on. Its worked every time. All i van think is that if the rubber membranes not quite positioned accurately, the valve part gets trapped between the two parts of the pump housing.

or have you already tried that?

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[Bejasus]

You did ensure that both of the retaining circlips either side of the piston were still there. I had the same symptoms after stripping mine and when I restripped it, I discovered that the circlip above the piston had broken and that once the piston had been pulled upwards, the stem just move down and up with no effect. Once I replaced the circlip, I had no further problems. The circlips are made of mild steel and corrode easily and also are not supplied in the overhaul kit. I got some from a Motor Trade suppliers.

<hr width=100% size=1><A target="_blank" HREF=http://www.arweb.co.uk/argallery/h00>h00's project</A>

 

[Roberto]

It took it off and mounted back a hundred times !
One of the screw casings was loose but apparently the other five kept it tight, the inside flapping parts of the membrane seemed to be ok every time..

thanks Jacket

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[Roberto]

The circlips were ok: when I replaced the piston oring it was a bit difficult to push-pull the piston, little by little it became a bit easier but still rather hard so I reckon the piston was doing its job and remaining firmly attached to the stem..

thanks anyway

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[Bejasus]

Hasn't rolled the 'O-ring' off again has it? Actually, ignore that. If it pumps out OK, then the piston must be working ok. Try disconnecting the flush water supply line and flushing it in both directions with a hose and the switch over to the correct position for flushing. You should be able to flush water into the toilet. Don't overdo the pressure though.

<hr width=100% size=1><A target="_blank" HREF=http://www.arweb.co.uk/argallery/h00>h00's project</A>

 

[quaelgeist2]

The intake/outlet lever only moves a little rubber flap (with a piec of brass attached) inside. If for whatever reason, the lever does not lift the flap enough, then the incoming water pushes down the rubber flap and thus blocks the inlet.

Before a recent overhaul, the flush position was not stable on our Jabsco. While pumping in, you would have to hold the lever towards flush, or it would slide back to empty bowl and do just that.

Taking off some material from the lever (<0.5mm) and the pumphousing where it goes against added the extra way that ensured stable inflow of water.

You may want to to try that. If my lousy description is too cryptic, just PM me and I elaborate a bit further.

chris

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[Roberto]

thanks will try that

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[Roberto]

thank you Chris it s all clear I will try that too, funny how these things work to 0.0000001mm tolerances !



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