Jabsco toilet water inlet anti syphon loop

Peter

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Just fitted a new anti sysphon loop on the inlet water to our manual jabsco toilet, previously just a direct line from inlet valve to toilet, toilet at water level. Now the toilet dosent work, any clues? A couple of points which might help:
-Even removing the anti syphon valve makes no differance and leaving the loop in place.
-Toilet still work when reconnecting directly to valve by orginal line.
-The anti sysphon valve only closes on pressure, not on suction which is what I assue it would see when I am using the toiletliet pump.
- Toilet is fairly old and has not been serviced apart from cleaning valves, but they look OK

Thanks

Peter
 

Blueboatman

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Try chucking a bucket of seawater down the bowl then whilst holding a finger over the antisiphon hole, pump until you feel the load come on the pump handle, release finger and keep pumping, does water continue to be drawn in now?
I would think next step is undo the 6 screws and examine/service flap valves and pump piston? Service kits readily available.
There are other forum threads on the importance of reassembling and getting those 6 screws to run down their original threads and not try to wind a new thread into the plastic, it ain't meaty enough and will strip.
 

VicS

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Just fitted a new anti sysphon loop on the inlet water to our manual jabsco toilet, previously just a direct line from inlet valve to toilet, toilet at water level. Now the toilet dosent work, any clues? A couple of points which might help:
-Even removing the anti syphon valve makes no differance and leaving the loop in place.
-Toilet still work when reconnecting directly to valve by orginal line.
-The anti sysphon valve only closes on pressure, not on suction which is what I assue it would see when I am using the toiletliet pump.
- Toilet is fairly old and has not been serviced apart from cleaning valves, but they look OK

Thanks

Peter
just to check.

The antisyphon loop and valve should be between the pump and the toilet bowl.

You have not fitted it between the inlet seacock and the pump have you ?


If that is correct then service the pump with the appropriate service kits

See the appropriate toilet spares and service kits at http://www.jabscoshop.com/marine/marine-toilets/toilets/manual-toilets/

The time perhaps to fit the new type "Twist and lock" pump
 
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Independence

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I had a similar problem once and I think due to a slightly under sized water inlet skin fitting. I was told it was a common problem and solved by disconnecting the pipe going to the bowl, create a seal by placing your finger over it and then pump a few times which would then create sufficient pressure to suck water through the pipework.

It worked for me!!
 

Caer Urfa

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Peter[/QUOTE]

Hi Peter
Fitted my Jabsco sea toilet two years ago and works fine, does the attached picture help you, other suggestions also worth checking as above posts.

Mike

DSCN2025_edited.jpg
 

mitiempo

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The pump on the Jabsco and similar heads is not able to pump properly with an anti-siphon between the intake seacock and the pump. That is why Jabsco ststes it should be between the pump and the bowl, in other words in the pump's outlet side and not the inlet side.
If you installed the anti siphon between inlet and pump, re-locate it and it should work as well as before it was installed. A service kit shouldn't be necessary unless it was before the anti-siphon was installed.
 

VicS

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If you installed the anti siphon between inlet and pump, re-locate it and it should work as well as before it was installed.
Absolutely, but note the Op says, "-Even removing the anti syphon valve makes no differance and leaving the loop in place. " and, "- Toilet is fairly old and has not been serviced apart from cleaning valves, but they look OK"

Something wrong if it wont pull water in over a loop on the inlet without a vent ( unless the loop is ridiculously high )

Similarly something wrong if it wont pump water over a correctly positioned loop

In view of the second statement about the age of the toilet and its past service history I would suggest it is probably time for a through overhaul, whether the valves look OK or not, as well as correctly fitting the loop if necessary of course.
 

homa

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Hi Peter

I did the same as you (fitted and anti-syphon loop) and realised that the syphon loop was not allowing the pump to suck.
I blocked the air vent with tape and managed to get it going again.
I now realise from the replies to your post that I should have put the anti-syphon loop between pump outlet and bowl inlet. Mikes photo shows this quite clearly.
If I were you I'd also give the toilet a service and add a drop of washing up liquid and water in the bowl. It will help the pump valves make a decent seal for the first few flushes.

Good luck
Homa
 
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