Joker valve

Stever00

When is a joker valve bad? Got photo of old one. Seems like too much light. Read where one guy used a Raritan duck bill type. Seems they would be less likely to have back flow if they would work in Jabsco.

Willhound

Yeah that valve is shot. Shoukd barely be able to see any light, preferably none. 

aero3113

Yea, definitely bad. I would think your original type valve would allow waste to flow better than the other pic you posted.

Liberty44140

Agree a little light is normal on a new one but that looks like too much...

Stever00

I should have new one first of the week. I'll take a photo of it and compare. The temp was about 50 degrees today. Not sure how temps affect that rubber as far as shrinkage and expansion.

Stever00

Here is a photo of a new joker valve. You can tell a lot of difference. Another quality product from China. Guess it will biodegrade like all Chinese plastic and rubber products.

Cableguy Greg

Plan on replacing it at least once a season. If you use the toilet a lot, then possibly twice a season. 

rasbury

So who is the fool that named it a joker valve cause it ain't no joke... 

Stodge

I  get a lot more life out of mine Greg.  One trick is to flush a bottle of mineral oil at the beginning of the season.  The oil help keep the rubber parts happy.  When we had a manual pump head I'd dump a bottle any time the pump started losing suction of if we went more than a month without using the head.

MarkB

Thanks goodness it's an easy part to replace!  Definitely time to replace that one ... depending on toilet use ... 1 to 2 years is the lifespan.

Stever00

On the Jabsco toilet discussion. Has anyone found an O ring in auto parts store that would work on the hand pump shaft. Already ordered  base gasket, top gasket and joker valve. Hate to buy kit just for the big O ring.  Not sure if there is a part number for just O Ring.

aero3113

If you can take measurements of the old O-ring, I bet you can find it at a store or online.

Stever00

I been reading where people use mineral oil, vegetable oil to to lubricate head pump. Many say this synthetic grease you can get at Harbor Freight is better .

LaRea

Humor me here.  Where exactly is the joker valve, and what happens when it fails? 

In 20+ years owning cruising boats, I have never changed a joker valve, and never had any problems with the head on any of my boats.  

MarkB

It is right where the toilet discharge connects to the pipe flowing to the waste tank. You should be able to access it from inside the head. It acts like a non-return valve, and prevents burb back.  When you flush contents into the waste tank, for a brief time the tank slightly pressurizes ... and gases can come back up the waste pipe and bubble out of the toilet ... so you get a stink.  If you see bubbles coming out of your head after you flush, it's likely the joker valve.

Willhound

Just a one way check valve to keep stuff from flowing back into the bowl after flushing. There is always (or should be) a rise in the waste line to a high point and then back down to the waste tank so that the contents of the tank can't flow back into the head. The joker valve keeps the liquid/waste whatever in that uphill portion of the line from flowing back. 20 years and never changed one? Is someone changing it out when they winterize your head? I've owned my boat 3 years and changed it twice already.

aero3113

@LaRea , what tank/toilet treatment do you use? Whatever your doing seems like it’s keeping the rubber parts conditioned. I had a manual flush on my 242 and it seemed like every season it needed to be replaced, sometimes twice. You will smell it if your joker valves are bad, also sometimes the system will not hold pressure. On a VacuFlush system there are 4 - 8 joker valves depending on the model.

Watch this video (They call the joker valves duckbills).

https://youtu.be/ENFjIj_niu0

 

TonyG13

I have to agree with @LaRea - on our old '94 Maxum, which we had for 20 years, I never changed anything on the head (manual pump-flush). Nothing ever leaked or smelled. Must have been one of the lucky ones? And I know our storage yard didn't touch it 'cuz they charge me when they just walk by the boat 

aero3113

On my 242 with a single joker valve, when it went bad, the bowl would fill slightly from the waste tank side.

LaRea

I had a Maxum 2400 for five years, a Rinker 342 for ten years, and my current Rinker 370 for seven years.  I've never had one single problem with the toilets (odor or otherwise). 

Every time I pump out, I dump tank deodorizer into the toilet ... the blue liquid for many years, and now Aqua Kem packets which are much easier to store and use.  The only time I've ever had any odor is outside the boat when I forget to add chemicals.  Flush an Aqua Kem and the odor is gone instantly.  

The head rarely goes longer than two weeks without exercise.  EDIT:  Except for winter layup, which is done with the same anti-freeze that everybody uses.

That's not luck.

Stever00

If any of you are cheap like me and start trying to find O ring for hand pump you may not find one.  Tried auto parts, Marvin's. Where I used to work we had a kit to make O Rings. Small fixture to cut end straight and hold inline to glue. Not sure what kind of glue it was but it was strong. They make that stuff odd size so you have to buy parts from them just like hydraulic trim tab hose people. I'm just going to put in new joker valve, top seal and bottom flapper seal and put some of that grease in it.  Hoping I can get MSD permit before long. Called guy near here who does them. Haven't heard back. Its stupid how they do that where I live. If they pass a law they should at least have people to help you comply with it.
Took several calls and emails to two water patrol just to find out who does them. The first one had retired. Not heard  back from the second guy. Must be a job no one wants.
Just heard on news where guy went missing up above Nikajack dam over month ago. They found his body just below Guntersville dam. That tells you how much rain we have had.

Stever00

https://www.gadsdentimes.com/news/20200218/body-found-at-guntersville-dam-traveled-from-chattanooga

Dream_Inn

I've had both the electric head and now vacuflush.  I changed out the joker valve on the electric I think twice in the 8 summers or so I had the boat.  Mainly for just a little backwash.  

Right now I'm in the middle of changing every dang part in my vacuflush setup.  It just does not seem to hold vacuum.  I have it out on a bench at home, so it's definitely something with the small tank/pump area.  The good news is that I've definitely made it quieter when it pumps.  

aero3113

@Dream_Inn , if you have it completely out, you might want to replace the tank seal also.

Dream_Inn

aero3113 said:

@Dream_Inn , if you have it completely out, you might want to replace the tank seal also.

What do you mean by tank seal?  Do you mean the one that goes all the way around with ~30 or more screws holding the top and bottom together?

I've been trying to think about a way to submerge the whole thing in water and maybe notice where are bubbles are coming out to show the vacuum leak.  

The thing is really starting to tick me off and I have maybe 2 weeks before I begin using the boat & need the head!.....maybe I should start another topic!

aero3113

@Dream_Inn , yes that’s correct. If you watch the video I posted, he replaces that also.

Stever00

I bought a new joker valve but decided just to get a new pump assy. Got one for 89.00 from marine place in Tn. I'm glad I did. That top gasket and base flapper looked like it was about flapped out. The plastic in those pumps are light as a feather and made in China. 
I bet there is a hugh profit margin. Especially as many times as you have to replace parts.
Be careful the chemicals you put in them to clean. The instructions tells all that.