Joker valve?

[Bossman]

Hello Peggy,

Hope you can assist on this prior to my unbolting everything.

Have a Jabco head, about four years old. We use it constantly for #1, dockside for other. Not a liveaboard but 2 of us on the boat about 4 days a week. Thousands of head cycles, hundreds of pumpouts at the dock station and offshore.

Problem: Head pressure now seams to be building. More and more difficult to evac bowl. Does not feel like friction, but pressure. Makes a new gurgling sound after bowl is empty, like a pressure relief. Problem intermittently goes away when seawater inlet is used, but not always. Dockside pumpout proceeds normally as near as I can tell. Offshore discharge thru macerator is uneventful.

Current troubleshooting: I have disconnected the vent hose at the holding tank top, put my thumb over the end of the vent outlet and then pumped the head a few times. When I release thumb, air escapes. Therefore vent is clear. Also, same head pressure problem while vent hose was disconnected. For argument's sake I checked the vent hose too by flushing water from the thruhull vent into a pan that I had put on top of the holding tank.

I disassembled the top of the head pump unit. Very simple mechanism and everything is clear and undamaged. Rubber bits are pliable and (now)clean of algea.

My suspicioun is now focused on the Joker valve inside the plumbing. Do you think this is a correct assumption and if so what precautions would you recommend while repairing? -Or- Is it likely something else with this type of head?

Thanks very much for you time and advice,

Russell

 

[Peggie Hall HeadMistress]

Maybe...

However, if it's been at least two years since the joker valve was replaced--and from your comments I'm guessing it never has been--you need to replace it anyway. That should be done as routine maintenance in all toilets. In fact, as much time as you spend on the boat, yours should be replaced annually.

Since you've ruled out a blocked tank vent, the two most likely reason for increasing backpressure are:

1. A failed wet/dry cam...a VERY common problem on Jabsco toilets built in the last 7-10 years that's due to either a tooling or mfr'g defect. The cam hangs, creating backpressure that feels just like trying to flush against a clog. Repair requires calling Jabsco for a new cam assembly and taking the pump apart.

2. Since you're a non-registered guest, you have no profile that would tell me whether you're in fresh water or salt. If you're in salt water, a buildup of sea water minerals in the head discharge line can reduce the diameter enough to just about block it completely and/or can clog up the joker valve enough to block it. If that's the problem, it'll be obvious when you replace the joker valve.

The average lifespan of Jabsco manual toilet is only about 5 years...IF it's been meticulously maintained--kept very well lubricated, sea water rinsed out of the pump, joker valve replaced regularly etc. Yours is 4 years old and has had higher than average use with minimal or -0- maintenance...so it's prob'ly time for a new toilet and good excuse to upgrade to higher quality.

I've never understood why some people use their marine toilets only for urine. When at home, you don't go down to the corner gas station when you have to pass solid waste, you use the toilet at home. Marine toilets are designed to flush both liquid and solid waste. Limiting use to urine only does not reduce the wear and tear on the toilet a bit....nor does it prevents clogs or other problems. It makes no difference in the holding tank or the plumbing either, 'cuz urine can produce just as much odor and permeate hoses just as quickly as solid waste. All you have to do is add a little water to bowl with a cup ahead of use to make the toilet on the boat as easy to use for solids as the toilet at home. It's as silly to avoid it as it is to avoid flushing TP on the boat.

 

[Roy10289]

Peggy is the expert here but just to add my experience with the joker valve.....
I have a Jabsco head also. I had a problem with water refilling the bowl after I would pump it dry. Replacing the joker valve fixed the problem. Personally,in my opinion,you can replace the entire head for not much more than the cost of the replacement parts on Jabsco products. I don't know if Peggy agrees,but I think that there are better products on the market than Jabsco.

 

[Ron20324]

Boss, there is also a "base valve gasket" (maybe part # 29043-0000 for yours?).It is located where the pump bolts to the base. The newer twist-lock version of the pump has an extension of the push rod which will push down on the BVG, holding it shut. It's a second way to block backflow.

 

[Bossman]

Beauty

Thanks Peggy and others. Outstanding info.
Will come in handy next week.
If it's only the joker then I get get going for about $14. Will inspect other parts as well. If it needs $80 rebuild kit then am looking at new head.

BTW - We use dockside head for "other" because the boat's holding tank is only 8 gal, which = about 3 days (using tank monitor) when used under current protocol. Which is perfect because that's when wifey goes back to work and I go sailing\discharge offshore. Also, dockside flushing is prefered for those types of things, especially by wifey.

 

[Broke sailor SV Marcell]

Hi Peggy: We avoid Number 2 when dockside so that we don't fill up the tank as fast thus requiring a pump out. We don't flush TP to avoid a accidental clog.

 

[Bossman]

Done

Fixed it.

Wasn't the head at all. The hose to the holding tank was chock full of a sandy filling. There was only about an 8mm hole in the center of the blockage all the way through. This was why all the pressure required to flush. Discovered this when removed joker valve.

Replaced hose and joker. All is well, works as smooth as new. However, it took 5 1\2 hours to disassemble the hanging locker in the head, destroy the old hose to get it off, then refit with new. What a $%#$! it is to get the hose off and on the holding tank in an unbelievably tight space and when the hose is an exact fit (and after you gouged the flange a little when getting old hose off). Crushing ribs, banging knuckles, hot, can't see anything under there, lot of cussing. Nearly gave up. Only a dab of 30-weight saved me, but it was still a battle.

I never ever never want to do this job again. Not really dirty or smelly, just tight and miserable.

Question: What was in the hose? Someone on the dock (WM had no idea) said something about calcification. Do you think that is accurate and if so, how do I PREVENT it?

Thanks,

 

[Bossman]

Discharge hose

Ok, found exact answers needed on other post in regular forum, "Fresh Water Head and Effect on Calcification? "

Thanks,