Jabsco head doesn’t pump out on wet mode

[benzy]

Have read a few similar issues but hoping someone can confirm the cause of this problem:

When flushing our head on “wet” mode, the bowl just gets more and more full. If I then switch to “dry” mode, it takes an inordinate number of pumps to get it empty again.

There is also an issue where sometimes when switching from “wet” mode to “dry” mode the pump is stuck, and I need to flick the wet/dry level back to “wet” then ALL the way over to “dry” for it to move.

From what I have read, this is probably a faulty wet/dry gate valve? Lots of people talked about this in relation to the stuck pump, but not the bowl filling up when pumping on wet mode. Can anyone confirm?

Btw I know this is not normal as our front heads works a charm. On “wet” mode one stroke puts in water and the other sucks it out again - never fills the bowl.

I have fully rebuilt both heads (with the rebuild kit, which does not include a new gate valve) so I’m confident that it’s not related to any other parts of the head.

Thanks

[peghall]

The need to jiggle the wet/dry lever is a strong indication that the wet/dry cam is hanging up...it's a common problem in Jabsco manual toilets. The only solution for that is, replace the wet/dry cam assembly.

However, that's not the reason you're having hard time emptying the bowl. There are several possible reasons for that: 1. a blocked holding tank vent that's pressurized the system, creating back pressure. However, if both your toilets flush into the same tank, you'd have the same problem with the other toilet too, but you don't.. 2. Sea water mineral buildup in the toilet discharge line has gotten thick enough to reduce the diameter of the hose enough to come close to blocking it. If both toilets get the same amount of use, that's unlikely--but worth checking anyway...but if that toilet gets 90% of the use, it's another strong possibility. 3. Somebody flushed something they shouldn't have, most likely a wet wipe. Have you had guests aboard recently?

That should be enough information to help you determine the cause of your problem. If it's none of the above, Paul Campagna is Jabsco's toilet tech support guru...his direct # is 978-282-5246

-Peggie

[benzy]

Thanks Peggie,

Fair enough on the wet/dry cam assembly maybe needing replacing. Will look into that.

Just to clarify on the bowl filling with water issue: the bowl is not “hard” to empty - the pump moves up and down just fine. But it does seem to take a lot of pumps to get it to empty. It almost feels as though it’s not sucking the water out, as in the stroke feels a bit too easy.

Also, something in particular is the fact that when on the wet setting, water comes in on one stroke but doesn’t really go out on the other stroke, so the bowl fills up (whereas our other head on wet mode sends in water on one stroke and takes it straight out again on the other stroke).

This has been a problem for two seasons. This head goes straight out (no holding holding tank or fancy valves). I also replaced the seacocks and all plumbing at the beginning of this season, so I’m sure it’s not a blockage of any kind.

Any other ideas?
Thanks

[peghall]

Any other ideas?

Just one: try replacing the joker valve. Here's why:

Most people think that the only thing the joker valve does is acts as a check valve to stop backflow from returning to the toilet or odor from the tank from escaping through the toilet. But that's not a joker valve's most important function...in fact, the joker valve is THE single most important replaceable part in a manual toilet.
Here’s how the discharge half of the pump works: On the upstroke of the piston, a vacuum is created in the area beneath the piston. This causes the joker valve to close tightly, and the flapper valve beneath the pump to open, allowing some of the contents of the toilet bowl to be drawn into the bottom half of the pump. Then, on the down stroke of the piston, the flapper valve is slammed shut, and the effluent is forced out of the bottom of the pump, through the joker valve, and off down the line. But when the joker valve becomes worn and/or there's a buildup of sea water minerals on it, it can no longer seal tightly on the upstroke of the piston...less vacuum is generated when you pump it. And as it becomes more worn less and less vacuum, till finally the bowl contents simply move up and down a bit, but don't go anywhere.

That seems to describes what's happening in your toilet.

If replacing the joker valve doesn't solve the problem, give Jabsco a call.

--Peggie

[benzy]

Thanks Peggie, that makes sense. Will take it apart and have a look next chance.

[Bill Youmans]

I had a sticky stiff Jabsco pump handle.
All it needed was SILICON GREASE, $4.00, rubbed small about on shaft of pump
handle. Perfect and top once a month or as necessary .

[sck5]

I took apart my jabsco pump assembly once to rebuild it. Then I discovered that a complete pump assembly only costs $20 more than a rebuild kit. When your head pump is all disassembled and you feel like you should eat a few antibiotics to kill whatever got on your hands, ask yourself this: "Would I pay $20 not to be doing this right now?"

https://www.defender.com/product3.js...4293&id=856627

[travellerw]

Originally Posted by sck5

I took apart my jabsco pump assembly once to rebuild it. Then I discovered that a complete pump assembly only costs $20 more than a rebuild kit. When your head pump is all disassembled and you feel like you should eat a few antibiotics to kill whatever got on your hands, ask yourself this: "Would I pay $20 not to be doing this right now?"

https://www.defender.com/product3.js...4293&id=856627

I agree with this %100. I recently serviced my Jabsco pump after 2 1/2 years of full time with our family of five. I even pulled apart the wet/dry gate assembly and cleaned everything up.

The only reason I did that was because down here the pump assembly is double that cost. If I could have bought the whole thing for $80, I would never have messed around with it.

Your easiest solution is to buy a new joker and pump assembly for under $100.. Just keep your old assembly for parts.

[Tillerjockey]

I had a similar problem and replaced the joker valve. Problem solved ! Thanks to everyone who posted the solution. One note of caution. When buying the joker valve hold it up to the light to make sure it's sealed tight. If you see any light coming through it, it won't seal. For this reason, don't buy on line unless you're happy returning defective valves.

[davefromoregon]

How frequently do you typically replace the joker valve? I have a jabsco toilet. Mine seems to fail a couple times a year. Is this normal?

[peghall]

Joker valves rarely FAIL, but they do wear out...how quickly depends on how much use the toilet gets. The slit and "lips" on a brand new joker valve are closed tightly...but are stretched each time a flush goes through it. The slit gradually opens up till eventually it becomes a hole instead of a slit. Twice a year would not be abnormal for a liveaboard on a boat with only one toilet.


But if you think that a joker valve's only function is to keep backflow from the toilet discharge line out of the bowl, you're wrong. Read my post #4 for the explanation of a joker valve's REAL function in any manual toilet and why the joker valve should be replaced at least annually.


Flushing longer in the dry mode will leave less water in the toilet discharge line to seep back into the bowl.



--Peggie

[travellerw]

Originally Posted by davefromoregon

How frequently do you typically replace the joker valve? I have a jabsco toilet. Mine seems to fail a couple times a year. Is this normal?

My last joker valve was in my toilet over 2 years. A couple of months ago I decided to change it "just because". I noticed no difference with the new joker installed.

However, at least once in its life I pulled it out and soaked it in muriatic acid. Before soaking I inspected it and it was clear that calcification had built up in the corners and was affecting it from closing properly. After that we began treating the toilet with muriatic about every 3 weeks to avoid that problem. When we pulled it out, it still looked like a new one.

If your valves are failing that fast, I would inspect them. I'm betting it will be calcification build up causing them to not function properly. As Peggy suggested, more flushing to push out the "offending material" will help. You can also try the muriatic trick (or vinegar if you are gun shy about muriatic).

[peghall]

A cupful of distilled white vinegar once a week flushed all the way through the system, followed after about 45 minutes with fresh water rinse, will PREVENT mineral buildup, but I wouldn't let the joker valve soak in in vinegar...that causes soft rubber to swell and distort.

--Peggie

[davefromoregon]

I do use distilled white vinegar every week or two. Though I thought that was for odor.

[newhaul]

Permanent cure for the issue is to change to composting head and never have to deal with bad joker valves again