Joker Valve not Working

[rogerthebodger]

I have a set of these to get at screws in difficult

places

 

[Bouba]

So your #9 was to land me in the same shit you're in. Thanks

No my logic is that you are complaining of backflow…the joker valves rarely wears out…others have hinted at pipe blockage…so I wondered if there’s a problem with the evacuation

 

[KevinV]

If you look at the photo in my op you'll see 2 screws, which are easy enough to deal with, but the bottom hidden one is a bitch. A regular size screwdriver is too long and a stubby is too fat to get under the housing even with the hose disconnected and out of the way. I've been using a small ratchet and screwdriver head. The housing seats in well to the base of the toilet but it's very difficult to exercise any precision in tightening the screws. No such difficulty on the stb side because the hose connection is on the inboard side and oodles of room.

I have one of these for that kind of thing - remarkably good.

Flexible screwdriver

 

[johnalison]

I have always regarded joker valves as being no more than a temporary way of stemming the back-flow. A clean valve, properly installed should be fairly effective but it is asking a lot of it to prevent any back-flow against quite a low pressure, scarcely enough to get the flaps to close. According to the installation, t may always be necessary to close one or two seacocks/valve to the holding tank.

 

[Irish Rover]

According to the installation, t may always be necessary to close one or two seacocks/valve to the holding tank.

Sorry, but I really don't understand this. I've never encountered a system with valves on the discharge hose between the toilet and the tank.

 

[pandos]

I have 2 Jabsco electric toilets on my boat. Stb side is no problem but since I got the boat the port side lets water seap back into the bowl after flushing. It's definitely from the discharge side. I've replaced the joker valve twice but it's still happening. Yesterday I took it off again and I soaked the housing in white vinegar and scrubbed it until it was spotless. .put it all back together and still the same. What am I doing wrong?View attachment 184341

Any chance your pump springs back or the electronics reverse it momentarily as it switches off..

Does it draw in the flushing water via vacuum in the style of a Lavac? If so is your inlet system clear?

 

[Irish Rover]

Any chance your pump springs back or the electronics reverse it momentarily as it switches off..

Does it draw in the flushing water via vacuum in the style of a Lavac? If so is your inlet system clear?

Water seeps back in slowly some time after flushing so I'd say not pump related.
Definitely not an intake vacuum problem. I flushed coffee to be sure it was discharge water returning.

 

[pandos]

Water seeps back in slowly some time after flushing so I'd say not pump related.
Definitely not an intake vacuum problem. I flushed coffee to be sure it was discharge water returning.

My thought was that the pump could be causing a back pressure which is distorting the valve..

I have a similar problem in my new to me boat and I think it is related to valves and diverters...

For a photo see

Thread 'Loo pipes.' Loo pipes.

 

[Irish Rover]

My thought was that the pump could be causing a back pressure which is distorting the valve..

I have a similar problem in my new to me boat and I think it is related to valves and diverters...

For a photo see

Thread 'Loo pipes.' Loo pipes.

Mine is a very simple system. The discharge hose from the toilet consists of about 1m of 25mm hose going into a 38mm hose connected to the bottom of the tank. I'm not sure if there's a non-return valve at the base of the tank but even if there's not the total volume of liquid in the entire discharge hose system is only around 1.5L and almost that amount is seeping back into the toilet. There's no immediate sign of water returning and it takes more than half an hour for it to fill back in which makes me doubt if it's back pressure from the pump.

 

[rogerthebodger]

Am I correct in assuming that the bottom of the waste tank is above the outlet of the head.

If that is the case, there will be a back pressure due to the waste being higher than the joker valve and as joker (flap NRV can tend to leak its thee design of the setup.

My waste tank is lower than the head and the head discharge pipe enters the waste tank through the top and not the bottom to prevent this back pressure.

 

[Irish Rover]

Am I correct in assuming that the bottom of the waste tank is above the outlet of the head.

If that is the case, there will be a back pressure due to the waste being higher than the joker valve and as joker (flap NRV can tend to leak its thee design of the setup.

My waste tank is lower than the head and the head discharge pipe enters the waste tank through the top and not the bottom to prevent this back pressure.

I would have thought the design of my system is very common for gravity discharge tanks. The joker valve is designed to close with back pressure which, as I've said, comes from around 1.5L of water. The exact same design with a slightly longer discharge hose is working perfectly on the stb side.

 

[rogerthebodger]

The issue with a gravity discharge waste tank is the head discharge IMHO should enter the tank at the top not the bottom.

The tank discharge clearly from the bottom and any pump out also at the top but directly above the gravity bottom discharge point to allow rodding if any blockage in the gravity outflow

 

[wonkywinch]

What am I doing wrong?View attachment 184341

A: Using different screw types to reassemble ;-)



On a more serious note, you may find as we did that there is another inline joker valve on the riser to the black tank. I had to change that to avoid the run back.

Not sure the second jubilee clip is doing anything on your set up, you can see the hose already bending away from the (short) spigot so the second clip only serving to pinch the pipe.

 

[wonkywinch]

Sorry, but I really don't understand this. I've never encountered a system with valves on the discharge hose between the toilet and the tank.

Beneteau fitted them to our 2016 Oceanis 38 and probably other models of their boats. The disadvantage is although you can take this unit apart, the joker valve is not the standard Jabsco size one and the supplier doesn't sell the valve on it's own, just a whole new fitting.

You can see the two different size pipe diameters, the instructions say to cut off the unwanted spigot if fitting to a larger pipe. Beneteau didn't bother doing this so the connection was liable to clog up as waste got trapped in the gap between small spigot and larger internal hose wall.

 

[Irish Rover]

On a more serious note, you may find as we did that there is another inline joker valve on the riser to the black tank. I had to change that to avoid the run back.

I'll check this. If there is it's most likely to be where the 25mm hose is connected to the 38mm.
The screws are as I found them so I assume someone lost one of the originals at some stage. I'll have a look at the jubilee but I'm pretty sure it's fully on the discharge port which is quite long.

 

[Irish Rover]

Beneteau fitted them to our 2016 Oceanis 38 and probably other models of their boats. The disadvantage is although you can take this unit apart, the joker valve is not the standard Jabsco size one and the supplier doesn't sell the valve on it's own, just a whole new fitting.

You can see the two different size pipe diameters, the instructions say to cut off the unwanted spigot if fitting to a larger pipe. Beneteau didn't bother doing this so the connection was liable to clog up as waste got trapped in the gap between small spigot and larger internal hose wall.

View attachment 184393

I was responding to #24 and I thought he was talking about a seacock type valve to manually open and close. I've actually been thinking about fitting a n/r valve in the discharge hose if a new discharge port doesn't solve the problem. I used one on my previous boat for a troublesome toilet and it solved the problem. There's not a lot of room for it low down but it could be done.

 

[Bouba]

I was responding to #24 and I thought he was talking about a seacock type valve to manually open and close. I've actually been thinking about fitting a n/r valve in the discharge hose if a new discharge port doesn't solve the problem. I used one on my previous boat for a troublesome toilet and it solved the problem. There's not a lot of room for it low down but it could be done.

Would a non return valve work better if it was placed as close to the joker valve housing as possible ?

 

[Irish Rover]

Would a non return valve work better if it was placed as close to the joker valve housing as possible ?

Definitely. That's why I said not much room for it low down.

 

[Irish Rover]

The issue with a gravity discharge waste tank is the head discharge IMHO should enter the tank at the top not the bottom.

The tank discharge clearly from the bottom and any pump out also at the top but directly above the gravity bottom discharge point to allow rodding if any blockage in the gravity outflow

It is what it is, but I still think bottom entry to the tank is not uncommon. Does it not connect to an internal pipe in the tank which takes the waste up to the top?

 

[rogerthebodger]

It is what it is, but I still think bottom entry to the tank is not uncommon. Does it not connect to an internal pipe in the tank which takes the waste up to the top?

The only pipe that does to the bottom of my tank is the suction outlet the enters the tank at the top then inside does to the bottom.

A top entry means that any seal leak will not cause any inside liquid will not seep out except a gravity discharge if the outlet valve is left open to the seacock will empty by gravity and no liquid will remain in the tank unless the valve is closed while in a marina / inshore water.

The diverter valve and the pipe to the bottom of the tank can be excluded so any liquid will be pumped from the head in the top of the tank flow to the bottom and if out at sea pass through the outlet valve which could just be the sea cock out to sea.

If the sea cock . outlet valve is closed the liquid stays in the tank until out at sea and the sea cock is opened and providing no blockage the liquid will flow out of the tank.

With a pump out deck fitting directly above the outlet if there is a blockage it simple to rod through the deck pump out down the outlet pipe and outlet sea cock.

Less valves to go wrong and blockages are easy to fix