At my wits end with this bloody boat head!

davethedog

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Morning all,

Any ideas on what could be causing an issue with our aft head (Jabsco) in that after flushing the bowl fills again (and yes I have changed the joker valve numerous times) and have checked for blockages in the hoses and all good (under 2 years old). Sometimes when manually pumping the pump would go very loose as if no pressure in the system, so thinking there may be an air leak somewhere?

A few days ago decided to bite the bullet and buy an electric conversion kit to see if that will help, and not really changed much at all as sometimes the water will not leave the bowl as if the pump is not priming, so could this be another indication of an air leak in the system somewhere?

Next stage is the check the Jabsco changeover valve and the holding tank hose to see if that is leaking.

Any other ideas, as said have done the following:
Changed the joker valve many many times.
Flushed through the outlet hose and no blockages.
Changed the anti siphon loop valve.
Changed from manual to electric flush.

All we want is for the electric heads to work all the time!!! And the bowl not to backfill!!!

Bloody boats

DTD
 
The Jabsco system is fairly simple, at least with the two that I have maintained and fitted.

How much flows back, there will always be an inch or so at the bottom but if flushed fully to clear the poo out, it should be clean.

You mention pressure in the system? Apart from the pump unit with the handle, nothing is pressurised. If it is that could be the problem. First, and an issue I learnt first was a previous owner had installed the joker valve back to front. If fitted correctly, then it might be a blockage in the outlet / holding tank section.
 
One of our heads inlets occasionally siphons very slowly if the switch is left in flush (water in) position but not when in pump out. The flushing water just trickles in very slowly until it fills to about 50mm below the bowl rim, then stops. Needs service kit at top of pump, likely a valve not seating properly. I thought it was joker, which I changed, until I sprinkled some talc around the bowl and saw the water was entering from top, not flooding from bottom via joker.
 
Thanks all and now have the electric flush installed and sometimes it will not seem to prime and discharge the water...I am at a loss!
 
Currently using it to discharge straight out so discounting the holding tank
Is there a possibility that the outlet is partially blocked. And only allowing some of "a delivery and relevant paperwork" to exit....I had this a few years ago and I deduced that it had been ongoing for some time...eventually the whole thing had become unusable. I had done the choker valve etc to no avail....

It is happening again now but only since I began to close the seacocks.

This leads me to wonder if inadvertently pumping into a closed/blocked outlet can cause internal damage in the pump internals/valves?
 
To be honest the last thing I would have done would be to add the complexity of an electric flush until resolved the root issue. A manual Jabsco loo pump is a simple beast - and can buy a whole new pump in a sale for about £75 (compared to £40 plus for a service kit).
I would have checked the holding tank for blockage and then slammed on a new manual pump - which generally solves this for at least another year.
Then could consider servicing the old pump at leisure to do the same swap over next year
 
The thing is the wife wanted an electric head anyway so was the most logical next step (and yes I know it is noisy!).

Kept the old manual pump just in case as was easy enough to swap them over and we also have the fwd heads we can use if needs be so really I suppose it is a first world problem.

DTD
 
This leads me to wonder if inadvertently pumping into a closed/blocked outlet can cause internal damage in the pump internals/valves?

Yes, when my outlet hose was a bit blocked, and you felt pressure against you when trying to pump, the choker/joker rubber valve could invert (turn inside out). Then, as I recall, you got run back into the bowl.

This was a simple system with no holding tank involved.
 
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