JABSCO joker valve, again!

[charley sheets]

The joker valve can flood your boat, or sink it. The little flapper valve must also leak by to let water into the bowl. Mud dobbers will plug the vent and cause bubbles to leak back into the bowl. Try leaving the pumpout cap loose enough to vent. I had a towel halfway through the joker valve on a Cat. 25 which caused it to pump very hard. The piping is quite stiff and should not bend, but the vent line can. Good luck, and please let us know what you find. Charley

[Wannabe-007]

Co-incidentally, I just watched this video clip yesterday...
Jabsco - Diagnosing Waste Back-flowing Into A Marine Toilet

[sneuman]

Originally Posted by 2Hulls

It could be that simple. I finally gave up on Jabsco and replaced with Raritan about 5 years ago. They still require joker valve replacement as well as seals, but they are better engineered products, IMHO. I have no regrets for making the switch.

Dave

My story exactly. The Jabsco's are poorly engineered units and once you try to service them, they're never right again. I too went to a Raritan about 5 years ago and have been happy with it.

Having said that, lime buildup causes a lot of problems. Use a dose of CLR (available at hardware stores) every month or so.

[Greenhand]

Y'all can stop JABSCO bashing: the vented loop was clogged. We had taken out the valve and cleaned it last time we had an issue, but I went back in and poked at the top, to relieve great pressure and odor. I then dipped a Qtip in the muriatic acid and poked around, then dipped many Qtips in water and rinsed inside and out. I suppose we should take out the whole loop and clean it? That will have to wait until we pump out in the morning.

I accidently dropped the screw cap for the valve in the muriatic acid, to much ill effect, so I ran out and bought a new cap and valve. Then I dropped the valve as I tried to install it. I hung upside down as far as I could, but I did not find it. Luckily, I still had the old one. Tomorrow, I may go out again to buy another cap and valve

PS: Does anyone know why the valve would squeak the first few flushes? These are the things the books don't tell you!

[Ex-Calif]

Originally Posted by Greenhand

Y'all can stop JABSCO bashing: the vented loop was clogged. We had taken out the valve and cleaned it last time we had an issue, but I went back in and poked at the top, to relieve great pressure and odor. I then dipped a Qtip in the muriatic acid and poked around, then dipped many Qtips in water and rinsed inside and out. I suppose we should take out the whole loop and clean it? That will have to wait until we pump out in the morning.

I accidently dropped the screw cap for the valve in the muriatic acid, to much ill effect, so I ran out and bought a new cap and valve. Then I dropped the valve as I tried to install it. I hung upside down as far as I could, but I did not find it. Luckily, I still had the old one. Tomorrow, I may go out again to buy another cap and valve

PS: Does anyone know why the valve would squeak the first few flushes? These are the things the books don't tell you!

I have a Jabsco manual - The only thing I do is lube the O-rings in the pump about once every 2 years.

I only use Vaseline. Squeaking indicates dry O-rings to me. I wouldn't be putting any vinegar in there.

[Greenhand]

Originally Posted by Ex-Calif

I have a Jabsco manual - The only thing I do is lube the O-rings in the pump about once every 2 years.

I only use Vaseline. Squeaking indicates dry O-rings to me. I wouldn't be putting any vinegar in there.

The squeak was definitely coming from the lazarette, where the vented loop is located. It only happened the first couple of pumps.

[ReMetau]

Originally Posted by charley sheets

The joker valve can flood your boat, or sink it. The little flapper valve must also leak by to let water into the bowl. Mud dobbers will plug the vent and cause bubbles to leak back into the bowl. Try leaving the pumpout cap loose enough to vent. I had a towel halfway through the joker valve on a Cat. 25 which caused it to pump very hard. The piping is quite stiff and should not bend, but the vent line can. Good luck, and please let us know what you find. Charley

What? A bad joker valve can not sink your boat if your system has properly installed vented loops.

[ReMetau]

We had so many problems with our 2 Raritan we'll never go back to one.

The times we have seen jokers fail prematurely are usually due to back pressure caused by over filling the holding tank and/or a clogged tank vent.

[thinwater]

After extended testing on multiple boats, Practical Sailor reversed its decision and rated the Raritan joker valve too pick. It is interchangeable with the Jabsco valve; I've had on in for 2 years. It is a tick harder to flush, but not troublingly so.

PS did not recommend any type of oil, and neither did Peggy. Both recommended annual lubrication with synthetic grease, per the manual. Oil is only if squeaks start and you want to get by for a few days. If oil is used, yes, rape seed oil and olive oil are best.

[Celestialsailor]

Originally Posted by 2Hulls

It could be that simple. I finally gave up on Jabsco and replaced with Raritan about 5 years ago.

Did the same and never looked back.

[Boatyarddog]

Try a filter screen on the inlet of the head, maybe debris in the water.


Sent from my iPad SV Cloud Duster

[Boatyarddog]

I believe most Jabsco heads have a locking pump handle. Newer ones for sure.
So if it's leaking, lock the handle. It's a positive stopper.


Sent from my iPad SV Cloud Duster

[ranger58sb]

Originally Posted by charley sheets

The joker valve can flood your boat, or sink it. The little flapper valve must also leak by to let water into the bowl. Mud dobbers will plug the vent and cause bubbles to leak back into the bowl. Try leaving the pumpout cap loose enough to vent. I had a towel halfway through the joker valve on a Cat. 25 which caused it to pump very hard. The piping is quite stiff and should not bend, but the vent line can. Good luck, and please let us know what you find. Charley

???

How would that work?

To get a towel -- you mean a bath towel or something? -- into our joker valve would require flushing said towel through the bowl... and almost nobody ever does that.

Originally Posted by ReMetau

What? A bad joker valve can not sink your boat if your system has properly installed vented loops.

Yep. And even if there were a problem with the loop, a joker valve on the discharge line that goes to a holding tank.... could only ever allow the holding tank's maximum to backflow into the bowl... and then elsewhere. (Yuck!) The weight of "stuff" in the boat would remain the same, no matter it's location.


-Chris

[svHyLyte]

Originally Posted by Greenhand

The squeak was definitely coming from the lazarette, where the vented loop is located. It only happened the first couple of pumps.

That "Squeek" is typically indicative of the "duck-bill" valve (similar to a tiny joker valve) at the top of the loop being installed backwards. If so, as air in the loop is pressurized by effluent being pumped from the toilet, it escapes through the (reversed) valve. With that, the lips of the valves vibrate together in a manner similar to a reed in a flute causing a squeeking sound. The lips of the duck-bill should be oriented facing into the loop, not outward, (which would also explain why your valve repeatedly clogs, which is unusual). One can dispense with the duck-bill valve entirely by using the fitting with a tube fitting and simply running a length of tubing (typically 1/4") to a point well above the heeled water-line level.

FWIW...

[Greenhand]

Originally Posted by svHyLyte

That "Squeek" is typically indicative of the "duck-bill" valve (similar to a tiny joker valve) at the top of the loop being installed backwards. If so, as air in the loop is pressurized by effluent being pumped from the toilet, it escapes through the (reversed) valve. With that, the lips of the valves vibrate together in a manner similar to a reed in a flute causing a squeeking sound. The lips of the duck-bill should be oriented facing into the loop, not outward, (which would also explain why your valve repeatedly clogs, which is unusual). One can dispense with the duck-bill valve entirely by using the fitting with a tube fitting and simply running a length of tubing (typically 1/4") to a point well above the heeled water-line level.

FWIW...

Nope, duckbill definitely down. That is the nice thing about doing it myself - Mr. Greenhand fully admits he may have done it upside the last time, since it is called a vented loop, not an anti-siphon loop.

It may have been the duckbill stabilizing on the upstroke, or something, though. It hasn't repeated since those initial pumps.