Why is my toilet bubbling?

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cardude01

Guru
Joined
Nov 26, 2012
Messages
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Location
USA
Vessel Name
Bijou
Vessel Make
2008 Island Packet PY/SP
It's always interesting with me and marine toilets...

My tanks shows almost empty (although my gauge is not very accurate), but I know it's not full.

Noticed the toilet bubbling after a flush today. Didn't know if it was getting ready to explode. Figured I would ask.
 
Does your model have a joker valve?
 
Does your model have a joker valve?


I really don't know. I'm such a marine toilet newbie.

The toilet is a Raritan manual pump model.

ImageUploadedByTrawler Forum1459809052.403526.jpg
 
Looks like a Raritan PHII marine head. They do have a joker valve and they are a regular maintenance item that should be replaced. If I recall correctly, there was a Practical Sailor article a while back that said that the Raritan, Jabsco, and Grocco valves are interchangeable.

Also a good idea to greese up the pump with Super Lube yearly. If I am right and that is a PHII, it is a solid manual head that works great, but still needs some annual maintenance. (when did I do mine last.....?)

BTW, if we are lucky, Peggy will chime in here, give you the correct information and save me from embarrassing myself.
 
Ah yes, the bubbling toilet. Been there, twice on two different boats. There are marine toilet experts on here far more knowledgeable than I am, but I've had that problem. Nearly empty holding tank both scenarios. Both boats, when we'd flush one head, the toilet in the other head would bubble. Both times it turned out to be a bad or weak joker valve -- the rubber one-way valve that makes sure the "material" in the bowl flows only one way, and not back into the bowl -- and a blocked vent fitting working together. Because we had floppy, worn out joker valves, when you'd flush one toilet it would push the waste fluid into the tank, displacing or pressurizing some air in the tank, and forcing it toward the other bowl. Both times the holding tank vents were also clogged, so the air pressure wouldn't release except by bubbling up into the opposite toilet bowl. Well, to be precise, with the Carver the vent blockage was spider webs blocking the vent outlet. In the Mainship it was a clogged or waterlogged charcoal filter in the holding tank vent line. The cartridge still worked a little, but was too restricted to let air flow freely enough to equalize the pressure fast enough to avoid the bubbling. Changed the joker valves, cleaned out the vent fitting on the Carver, changed the charcoal filter on the Mainship, and the bubbling went away.
 
I had that same model X2 on my last boat, except with the electric package. You need to buy the maintenance kit. You really should use all of the kit, though I often just replaced the joker.

ZZ19260_L.jpg
 
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It's always interesting with me and marine toilets...

My tanks shows almost empty (although my gauge is not very accurate), but I know it's not full.

Noticed the toilet bubbling after a flush today. Didn't know if it was getting ready to explode. Figured I would ask.



It's just passing gas to repay you for the indigneties you bestowed upon it.:whistling:
 
BTW, get a mask when you do this particular job.

And get lots of rags to place under the toilet when you undo it. Have a trash bag with ties at the ready as well.
 
BTW, get a mask when you do this particular job.

And get lots of rags to place under the toilet when you undo it. Have a trash bag with ties at the ready as well.


Well sh£t, that's sounds wonderful.

What twisted soul named this thing the joker valve? SMH.
 
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Well sh£t, that's sounds wonderful.

What trusted soul named this the joker valve?

It's not that big of a job. And it doesn't have to be a dirty one either.

Just shut off the incoming raw water to the head and flush it out with fresh water mixed with what ever soap/pine cleaner/degreaser solution tickles your fancy. Let the mix sit for a bit, then flush well with clean fresh water before you disassemble the head.

I had so many of those heads on the GBs I used to manage for charter that I could take one apart, rebuild and reinstall it in 20-30 minutes.

They are a very good manual head. And as mentioned lube it with a Super Lube as you assemble it.
 
Cool. Thanks.

I'm intimidated by toilets.
 
Greetings,
Mr. 01. Do what Mr. 11 suggests and I would add, pump out your holding tank before tackling the "throne". I replaced the joker valve last season in our Raritan Crown with no odors or "surprises". At the same time I cleaned up the impeller and some of the associated workings. A bit messy but really straight forward.
 
Capt Bill is right, it isn't that big of a job. As RTF said, pump out your holding tank and take the opportunity to flush the tank well with fresh water. I usually will do fresh water rinses when I empty the holding tank. Also backflush the vent tube while you are at it. (ie train a hose stream of fresh water on the vent as you are pumping the tank out) Keeping that clear will help avoid problems.

I don't think it is that messy of a job.
 
Yeah right.

Report back after you have done it. :)
 
I hope not...I'm having the same bubbling issue...guessed it was a clogged vent but I can't get at the hull fitting...I don't bend that way anymore. I pulled the hose from the tank end and holding it up higher than the hull fitting filled the hose with a sewer digester...the vent was dripping outside slowly when I left it...also burned out the macerator pump trying to fix this...arrrgh!
 
I hope not...I'm having the same bubbling issue...guessed it was a clogged vent but I can't get at the hull fitting...I don't bend that way anymore. I pulled the hose from the tank end and holding it up higher than the hull fitting filled the hose with a sewer digester...the vent was dripping outside slowly when I left it...also burned out the macerator pump trying to fix this...arrrgh!

Again, if you have a holding tank that you pump out, this is easy to avoid. Just backflush the vent every time you pump your tank. One of the reason I do it myself. I always rinse my tank a couple times after pumping and always run fresh water from a hose over the tank vent when pumping for a short bit of time. The pump draws fresh water into the vent at a pretty fast rate to back flush the vent keeping it clear.

Now, I don't have any type of vent filter on the vent as I want as much O2 to get into the holding tank as possible. I may have to rethink my system as I move to a freshwater flush system.
 
It's always interesting with me and marine toilets... My tanks shows almost empty (although my gauge is not very accurate), but I know it's not full. Noticed the toilet bubbling after a flush today. Didn't know if it was getting ready to explode. Figured I would ask.

Whizzit that the joker valve is the first thing anyone suggests is the culprit for ANY sanitation system problem? I get emails from people whose toilet has decided not to bring IN any flush water, and the first thing they say they did was check the joker valve.

Most likely this problem isn't the joker valve or even in the toilet...the holding tank vent is blocked. All tank vents--water, fuel and waste--have two primary functions: to provide an escape for air in the tank displaced by incoming contents and to provide source of air to replace tank contents as they're drawn out. When a waste tank vent becomes blocked, air can't escape through the vent so the tank becomes pressurized, creating backpressure as the air seeks to escape wherever it can...the toilet discharge line is the line of least resistance. And that's the most likely reason your toilet is "burping." A blocked tank will also make it impossible to pump more than a gallon or two out before the pumpout or macerator pump pulls a vacuum. An especially strong pumpout pulling against a blocked vent can even implode a tank. And you weren't too far off when you wondered if your toilet was getting ready to explode, 'cuz if a tank becomes sufficiently pressurized, it can cause an eruption back through the toilet or even burst the tank.

Tank vent blockages are especially common in the spring 'cuz mud daubers just LOVE to build their nests in vent thru-hulls. So before you do anything else, get out a screwdriver or an ice pick or whatever works and scrape/dig whatever has set up housekeeping in your holding tank vent thru-hull. And you do that from OUTSIDE the boat. Don't use the toilet again or attempt to pump or dump the tank until you're sure the vent is clear. Chances are, if it's been at least several hours since the toilet was flushed, enough air will escape through the toilet to relieve the pressure, but I'd still be verrrrry careful when you open the cap on the decK pumpout fitting. And don't even THINK of removing the vent line from the tank until you're 100% certain the system isn't pressurized.

If your vent thru-hull is the usual cap with a slit or a few tiny holes in it, best thing you can do is replace it with an open bulkhead or "mushroom" thru-hull that you can stick a hose nozzle up against and backflush the vent line to keep it clear. As is true of most things, prevention is easier than cure.

Dave, you said, " I may have to rethink my system as I move to a freshwater flush system."

Why? As far as the holding tank is concerned, flush water is flush water...whether it's fresh or sea water.

Cardude...I'll be glad to help you sort out how your toilet--the whole system--works and how to maintain it. It's not rocket science, just a short learning curve that, once you understand it, will help you prevent problems instead of fixing 'em.
 
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Dave, you said, " I may have to rethink my system as I move to a freshwater flush system."

Why? As far as the holding tank is concerned, flush water is flush water...whether it's fresh or sea water.

So as not to hijack this thread, I started a new one....
 
I've done it a few times. Much easier on the Raritan than my prior manual head.

Was referring to the lack of smell not the difficulty level of the job - it is one of the easier jobs - except for the smell!
 
Whizzit that the joker valve is the first thing anyone suggests is the culprit for ANY sanitation system problem?

Thing is, it certainly sounds like the thing hasn't been maintained since he bought the vessel.

So, since he should do the maintenance anyway, I would start with that and see where he is before he starts anything else.
 
Whizzit that the joker valve is the first thing anyone suggests is the culprit for ANY sanitation system problem? I get emails from people whose toilet has decided not to bring IN any flush water, and the first thing they say they did was check the joker valve.

Most likely this problem isn't the joker valve or even in the toilet...the holding tank vent is blocked. All tank vents--water, fuel and waste--have two primary functions: to provide an escape for air in the tank displaced by incoming contents and to provide source of air to replace tank contents as they're drawn out. When a waste tank vent becomes blocked, air can't escape through the vent so the tank becomes pressurized, creating backpressure as the air seeks to escape wherever it can...the toilet discharge line is the line of least resistance. And that's the most likely reason your toilet is "burping." A blocked tank will also make it impossible to pump more than a gallon or two out before the pumpout or macerator pump pulls a vacuum. An especially strong pumpout pulling against a blocked vent can even implode a tank. And you weren't too far off when you wondered if your toilet was getting ready to explode, 'cuz if a tank becomes sufficiently pressurized, it can cause an eruption back through the toilet or even burst the tank.

Tank vent blockages are especially common in the spring 'cuz mud daubers just LOVE to build their nests in vent thru-hulls. So before you do anything else, get out a screwdriver or an ice pick or whatever works and scrape/dig whatever has set up housekeeping in your holding tank vent thru-hull. And you do that from OUTSIDE the boat. Don't use the toilet again or attempt to pump or dump the tank until you're sure the vent is clear. Chances are, if it's been at least several hours since the toilet was flushed, enough air will escape through the toilet to relieve the pressure, but I'd still be verrrrry careful when you open the cap on the decK pumpout fitting. And don't even THINK of removing the vent line from the tank until you're 100% certain the system isn't pressurized.

If your vent thru-hull is the usual cap with a slit or a few tiny holes in it, best thing you can do is replace it with an open bulkhead or "mushroom" thru-hull that you can stick a hose nozzle up against and backflush the vent line to keep it clear. As is true of most things, prevention is easier than cure.

Dave, you said, " I may have to rethink my system as I move to a freshwater flush system."

Why? As far as the holding tank is concerned, flush water is flush water...whether it's fresh or sea water.

Cardude...I'll be glad to help you sort out how your toilet--the whole system--works and how to maintain it. It's not rocket science, just a short learning curve that, once you understand it, will help you prevent problems instead of fixing 'em.


Oh yeah. I forgot about that tank vent! I will check that first. Thanks!

Peggy, I bought your book and read it, but I'm still uncertain about the system. I've had an ongoing battle with some smell issues but started using some Nolfex and keeping the holding tank rinsed out better. Boat a smells better, but when I lift the hatch where the hoses are it's still pretty smelly down there. Did the rag test and it came away smelly so I guess I know what needs to be done eventually. ?
 
Dude, you're hosed.... :)
 
Can't you hire the marina to do the stinky stuff?


I really don't like hiring people. I prefer to whine while I flail around and attempt to repair things myself. ?
 
Loopy Kiwi had problems with his vents this link shows some of the details he found when he replaced the lines with bigger, its interesting he found screens on the vents some pic's in his blog


Loopy Kiwi
 
Can't you hire the marina to do the stinky stuff?

The problem as I see it is this. Say you hire a dock monkey to pump your holding tank. Are you certain they will flush out your tanks twice after pumping it? Are you certain they will backflush the vents in the process?

I don't like pumping my holding tank, but it is quick, easy, and I want it done right.

The other thing is that pumping the holding tanks on my boat is one of the few things that I actually feel competent doing.:D
 
ok...I am going to cut the vent off from the outside and try to fish another thru the hull..hopefully a better type as I have the same fuel vent type there now...hey experts..should the vent hose be straight out or should there be a curve to the hose to prevent odors or back-up?(like a p-trap). mine seems to have a dip down about 12" mid way in its travel to the outer vent...?
 
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