Another head question.

[BonesD]

I have a Jabsco Twist n lock manual head

I have question about refilling the bowl with water for the next use.
Instructions say to flush the black valve position selector should be chosen,
Then move lever to the left to select the white valve position.

At this point should I be able to pump in some standing water and have it remain in the bowl?

If I make full strokes on the handle water is coming in on the up stroke but exhausting on the down stroke.
If I make very short quick strokes I can get a head of water built up that will remain in the bowl. I just discovered this trick. I had been partially filling the bowl from the flexible shower head.


Thanks

 

[IRENE]

Ahoy Ricardo,

We had that appliance in a previous rig. IIRC, one lever position allowed water into the bowl, and the other did not. Hope this helps.

Bella

 

[BonesD]

Thanks El Jeffe!
It’s coming in but retreating for some reason as if a one way valve is not doing it’s job.
I bought a new joker valve but never replaced it. I don’t know if it has anything to do with this issue.
Appreciate it.

 

[Comodave]

If it has been more than a year or so then the joker valve most likely needs changing. No matter what head you have. They don’t last forever.

 

[HeadMistress]

At this point should I be able to pump in some standing water and have it remain in the bowl?

No. Manual marine toilets and most electric toilets aren't designed to hold water in the bowl. If you want to add water to the bowl ahead of use--which you should always do ahead of solid waste, use a cup from the sink. The water will drain out...how fast it does depends on how long it's been since the joker valve was replaced. It should be replaced at least annually if you're a "weekend warrior," at least every 6 months if you're a live aboard.


The wet/dry lever: use it in the wet position to wet the bowl ahead of use, the dry position to pump bowl contents out, then back to the wet position just long enough to rinse behind the flush. If you do it that way instead of always using the wet position except to remove the last bit of water from the bowl you can double the number of flushes your tank can hold.


--Peggie

 

[HeadMistress]

I bought a new joker valve but never replaced it. I don’t know if it has anything to do with this issue.

It has everything to do with it, plus a lot more. This should explain why it should be replaced at least annually if you're a "weekend warrior," at least every 6 months if you're a live aboard:

Joker valve 101 (excerpt from my book)
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 the joker valve's LEAST important function...in fact, the joker valve is THE single most important replaceable part in a manual toilet. Here's why:

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 over time the joker valve becomes worn...the slit becoms a hole and/or there may also be a buildup of sea water minerals on it. As it becomes worn, it can no longer seal tightly on the upstroke of the piston so less and less vacuum is created, requiring more and more pumping to move bowl contents.

You prob'ly won't notice the loss of efficiency at first because it's so gradual. But I guarantee you that if it's been two years or longer since you replaced the joker valve, you need to pump the toilet at least 50% more times to move the bowl contents to the tank or all the way out the thru-hull....IF they're getting there at all any more.


And btw...there's a lot more useful info in my book (see link in my signature below) that based on your questions I think you can use. Its title (my publisher's idea) is a bit misleading...'cuz although it does deal with every source of odor on a boat and how to cure, or better yet PREVENT 'em, it's actually a comprehensive "marine toilets and sanitation systems 101" manual that explains the laws, describes all the types of systems and how they work, and will help you learn how to operate and maintain your system to prevent 99% of problems instead of having to cure 'em. 'Cuz you get to do any preventive maintenance on your terms when it's convenient...the need to cure a problem never happens when it is!



--Peggie

 

[HopCar]

These piston pump toilets are interesting in that there are actually two pumps within that single cylinder. There are two sets of intake and discharge valves.

The bottom of the piston draws black water from the bowl on the up stroke and pushes it out through the joker valve on the down stroke. It does that every time you operate it.

The other pump is the top of the piston. Normally it draws clean water in on top of the piston on the down stroke and pushes it to the bowl on the up stroke.

Here is where it gets interesting. When you flip the lever it opens the discharge valve of the top pump. This allows the piston to draw air into the top chamber from around the toilet bowl rim. This prevents water from being sucked into the top chamber.

This means you can stop water from coming in when you operate the pump but it will always discharge water from the bowl. There is no way to turn off the discharge side of the pump.

 

[BonesD]

Thanks Hopcar, Peggie, and Comodave.
Your information is fantastic.
I have had the boat just over a year and have only utilized the head a few times and have to read the directions each time. Also as infrequently as it’s been used I haven’t noticed that it’s iability to dispose of stuff has declined or not.
If I can find the new valve I bought 6 months ago, tomorrow will be joker valve day.
Thank you all.
Bones

 

[Comodave]

Hope we helped. Get a bunch of disposable gloves and paper towels...

 

[BruceK]

IIRC, the joker valve is located where the outlet pipe is clamped on, easy job depending on access, not overly , flush it a few times beforehand. Looks like you have the Instructions.

 

[BonesD]

I found the new valve. The replacement might be the easiest plumbing job I have ever had.
The old valve didn’t look bad but replacing it is still a good idea. It did not change the function at all so I imagine there wasn’t a problem to begin with just me being unaccustomed to the way it works.
I don’t know if all Jabsco’s work the same but if you want some standing water n the bowl without adding it from another source the short stroking method with the valve in the open position. Works for me.
Thanks for the help everyone.

 

[HeadMistress]

Get a bunch of disposable gloves and paper towels...

Better way: Wear disposable gloves if you want to or just wash your hands very thoroughly when you're done. Run a couple of gallons of clean FRESH water through the toilet and pump several times in the dry mode to remove as much water as possible before removing the toilet discharge fitting...Put a plastic waste basket liner under it to catch any drips. Swap out the joker valve, reattach the fitting. You shouldn't need more than one or two paper towels.

When re-attaching the discharge fitting to the pump, be careful not to OVER-tighten the bolts...the flange on the joker valve is the rubber gasket that seals the connection. Over-tightening the bolts will "pucker" the rubber around 'em causing leaks. So start with just 1/4 turn past hand tight...flush the toilet. If the connection leaks, just another 1/4 turn more...till you stop the leak. Carefully collect the waste basket liner and call this job done.


And btw, Bruce...If it's been so long since you replaced the joker valve on your toilet that you have to preface your comment with "IIRC, the joker valve is located..." yours has to be looong overdue for replacement!


--Peggie