Squeaky Duck Bill Valve on Vented Loop??

[Bob Pullen HC-33 1981]

Just redid my sanitation lines aboard my Hunter 33 (1981) with all new 1.5" sanitation hose, etc, from toilet to through hull, including holding tank and Y valve.
Also swapped out the 1.5" Vented Loop (siphon?) -- the old stuff was original, cracked and rotting, plugged, etc...
I have the system connected as per the standard setup (see attached)
I am noticing a slight squeak when I pump the clean new system. It is coming from the "duckbill" valve at the top of the vented loop. It usually occurs towards the end of the flush. Just been flushing water at this point.
Any ideas, suggestions or advice will be gratefully appreciated.
Many thanks
Bob Pullen
S/V Seanorita
Mexico

 

[RichH]

Now you've experienced how the sound producing reed inside a bagpipe works.

the problem is that the valve insert isnt totally closing (causing the valve lips to vibrate); and, it either needs cleaning or gentle 'reshaping' so that it totally closes. If the sound continues, clean it again this time in warmer water, or replace the valve ...

..... or retune the drones on yer pipe to match, laddie.

 

[kloudie1]

Bob, that is the sound of the valve doing its job.. The water continues past the high point and the anti syphon opens and squeeks a little admitting air to break the syphon then stops when the pressures all equalize ..or the next slug of water pressurizes the loop as it pushes the previous slug and the little air pocket out.. don't worry if it is squeeking right at the end of the stroke, but I would worry about effluent if it squeeks when you begin the pump stroke.

 

[higgs]

Best to get the sound out with a new valve. You don't want that valve to start letting stuff back into the bowl when your heeled 20 degrees to the head side of the boat. i know from experience what an unpleasant situation that is.

 

[Peggie Hall HeadMistress]

If your system is installed exactly as illustrated...

You need one more vented loop...in the toilet INTAKE. Not in the line between the thru-hull and pump, but between the pump and the bowl. See the installation instructions for your toilet for specific instructions to install the intake vented loop.

 

[Peggie Hall HeadMistress]

Air valve in a vented loop has nothing to do with backflow

Best to get the sound out with a new valve. You don't want that valve to start letting stuff back into the bowl when your heeled 20 degrees to the head side of the boat. i know from experience what an unpleasant situation that is.

It's the height of the loop--which doesn't even have to be a VENTED loop--above the tank that prevents waste in the tank from running back to the toilet...any air valve in a vented loop has nothing to do with that.

There's actually an easier way to prevent back flow AND waste spilling out the vent when you're heeled..put the inlet and vent fittings on the tank as close to the centerline of the boat as possible and away from the hull.

I'll leave it there for y'all to figure out HOW that prevents waste in the tank from flowing out the vent or back toward the toilet.

 

[higgs]

Leave it to Peggy to point out the obvious the rest of us miss.

 

[catsailor]

There's actually an easier way to prevent back flow AND waste spilling out the vent when you're heeled..put the inlet and vent fittings on the tank as close to the centerline of the boat as possible and away from the hull.

I'll leave it there for y'all to figure out HOW that prevents waste in the tank from flowing out the vent or back toward the toilet.

I've worked with gasoline and chemical trailers that had a vent (presure relief) mounted away from the center; the result was generally highway closure and a lot of expense. The force on the underside of an opening or vent, when the liquid slaps up either in trafic or a seaway, can be considerable. As Peggy has criptically pointed out, it doesn't slosh in the middle. The practical and reliable solution, in the long term, was always to move the vent.

 

[Bob Pullen HC-33 1981]

Bagpipes in the head - badly seated duckbill?

Thanks for all the help.
Luckily the v.loop is installed against a bulkhead almost on the centerline.
However, I do believe the incorrectly seated valve is probably mostly responsible. I just got it...brand new...nothing other than seawater has been flushed through the system at this point. Not clogged.
However, on the long ride back to where we are now docked, I did take the brand new v.loop apart, unscrewed the top, and blew air through the hole on the top of the valve, at which time the little rubber valve popped out.
I placed it back in, but perhaps it is not positioned as it should be.
The duckbill is pointiing down, and the hole at the top of the duckbill is flush with the flat top of the screw off cap.
Any suggestions?
Thanks again for the assistance and advice. Having all this experience from sharing folks has been one of the most valuable resources in keeping Seanorita running. Very grateful.
Bob

 

[Peggie Hall HeadMistress]

Nope...no cigar...it's actually MUCH simpler than that

I've worked with gasoline and chemical trailers that had a vent (presure relief) mounted away from the center; the result was generally highway closure and a lot of expense. The force on the underside of an opening or vent, when the liquid slaps up either in trafic or a seaway, can be considerable. As Peggy has criptically pointed out, it doesn't slosh in the middle. The practical and reliable solution, in the long term, was always to move the vent.

For the sake of illustration, let's assume that the toilet and tank are on the port side of the boat. If the inlet and vent fittings are outboard--next to the hull--on the tank, waste will run into the vent line and toilet discharge line when the boat heels to port and spill out the vent and run back to the toilet. But if the inlet and vent fittings are INboard--toward the centerline of the boat--on the tank, when the boat heels to port, waste in the tank runs away from 'em, toward the hull...so waste doesn't spill into those lines. When the boat heels to starboard, those lines will be running uphill, so while tank contents can spill into them, it can't go very far.

Sometimes, it's what's most obvious that's the hardest to see.

Btw, Bob...Is there a vented loop in the intake?

 

[Bob Pullen HC-33 1981]

vented loop on ?

Hi Peggy
No vented loop on intake.
Yes, I'm sure it would be much safer.
I have a 3 yr old Jabsco...just when they came out with the lock on the handle...so it seems there are 2 ways, on the unit, to seal out incoming water. Now given your dislike for the model, which is understandable when seen in comparison to the existing substitutes...it is built of rather thin plastic...and please don't mention the 6-screws on the cover...I still see them in my nightmares.
However, it is extremely well matched to the circumstances (we have a dock with a head next to us, and the system is not used very often, and always by me...only!!). Yes it is an inferior product when matched to the competition, but it has handled the task at hand very well, which has resulted in a good bang for your buck. I treat it with kids gloves, and keep it lubricated as per the right way, now. The price was extremely right...for a variety of reasons it got delivered to my boat, in mexico, crated, for free.
At one point I did think it was getting clogged, and took it apart before reading the forum posts...6-screws came off...but then once I noticed the quality of the plastic, I was able to re-attach with infinite care, and successfully. read the forum post haste, and then cleaned it the right way...wasn't clogged, which led to the project to replace the old cracked hose and vented loop all the way to thru-hull.
Anyway, sorry to digress.
I do feel that having the 2 options to lock out water from the unit, may allow me to move the "vented loop on intake hose" to the back burner project arena.
Any suggestions to contrary are definitely to be entertained.
However, it seems that to stop the bagpipes from the outake vented loop, I might want to take the vent cap back off and try to reseat the duckbill valve, true?
I wiill postpone this to the morning, just to keep in line with the first step in all projects. Procrastinate.
cheers
Bob

 

[DannyS]

I think I agree with kloudie1 that the squeek is the valve doing its job. I installed a vented loop in my bilge pump discharge line because I was getting a siphon into the boat when under power (long story but the siphon hasn't returned since installing the vented loop). My loop squeeks at the end of the bilge pump cycle when the water between the high spot in the loop and the bilge drains back. That squeek lets me know its working and I don't have to worry about running down and checking the bilge.

 

[Peggie Hall HeadMistress]

Quality of toilet--or lack of it--has nothing to do with...

...whether a vented loop in the intake is needed. One is needed for EVERY manual toilet that's installed at or below waterline...which includes your boat. The installation instructions for every toilet--including jabsco-- include instructions for installing one. You might want to read 'em...or at least see "figure 1" on page three of the installation instructions for your toilet:
http://www.ittflowcontrol.com//files/29090_29120_toilets_0406_data_sheet.pdf

You're wrong in thinking that the "twist 'n' Lock" function in the current Jabso toilet seals out incoming flush water It only blocks waste backflow from the head DISCHARGE line...it has nothing whatever to do with flush water intake. You didn't mention what you consider to be your second level of protection against water outside the boat seeking its own level inside the boat via the toilet bowl, so I dunno whether you're wrong about it too. But I'd bet real money that you are. :dance:

 

[Bob Pullen HC-33 1981]

being wrong again and again...Peggy

Hi Peggy
just to satisfy your bet, the 2nd level, as I mentioned in a prior post, is the second valve/lock feature on the toilet (a switch at the top of the pump section), which indicates by the drawing above it, that it is either allowing incoming water or not, when the pump handle is pumped. I really don't care if that makes you feel like a winner or not.
I'm sorry if I alluded to the quality of the toilet being related to the need for a vent loop.
That was definitely not intended.
I mentioned that I knew about your aversion to this model/manufacturer...not that I really care, as I was hoping to point out, since the utility of the animal has been a perfect match to the conditions, price included.
I don't intend to use this forum as a means to satisfy a need to be right, I've got too much fun in front of me by being able to sail everyday, so please don't need to reply.
I was seeking advice or suggestions from folks who had encountered the squeak in the vented loop, remember? Thanks for your concern about the need for a vented loop on the intake...or was the concern more about the need to help readers understand how much insight you have into all head matters?
cheers
Bob

 

[Maine Sail]

Hi Peggy
just to satisfy your bet, the 2nd level, as I mentioned in a prior post, is the second valve/lock feature on the toilet (a switch at the top of the pump section), which indicates by the drawing above it, that it is either allowing incoming water or not, when the pump handle is pumped. I really don't care if that makes you feel like a winner or not.
I'm sorry if I alluded to the quality of the toilet being related to the need for a vent loop.
That was definitely not intended.
I mentioned that I knew about your aversion to this model/manufacturer...not that I really care, as I was hoping to point out, since the utility of the animal has been a perfect match to the conditions, price included.
I don't intend to use this forum as a means to satisfy a need to be right, I've got too much fun in front of me by being able to sail everyday, so please don't need to reply.
I was seeking advice or suggestions from folks who had encountered the squeak in the vented loop, remember? Thanks for your concern about the need for a vented loop on the intake...or was the concern more about the need to help readers understand how much insight you have into all head matters?
cheers
Bob

Bob,

I highly doubt Peggy is trying to just be right, she is trying to help you not sink you vessel and giving advice based on solid, well advised, industry recommendations. A vented loop is recommended on the intake because heads are not fool proof, BTDT. There have been many boats that sunk from a siphon in the head intake line. My own boat did not have one when we bought her and the PO had installed a PVC shut of valve at the head intake to solve a "problem" where when heeled the toilet would overflow and begin to siphon into the boat. This despite the toilet valve being closed. He did not understand plumbing very well. When we bought her I simply and immediately installed a siphon break in the line between the pump and bowl. Simple, cheap, and my boat will not sink if I forget to close a valve. I also clean my siphon breaks yearly as a good maintenance measure. In short there is good reason the head manufacturers recommend a siphon break in the intake line and as someone who has spent her entire career in the marine sanitation industry she is giving sage advice. I don't see her as trying to be "right", just safe...

Duck bills can & do make noise when they are "breaking" a vacuum, like towards the end of a pumping cycle when it is allowing the liquid to low to the tank from the high spot and break a vacuum in the line..

 

[Bob Pullen HC-33 1981]

I beg to differ...

As I mentioned in a prior post...I AM AWARE THAT I NEED A VENTED LOOP ON THE INTAKE HOSE...
don't know how to make that clearer!
I know it is a safer setup, but since you don't know the list of other items I am working on at this time, I do believe that in putting it towards the back burner, is justified, but I am not asking for you to agree with me.
However, the question being asked was related to a squeak in the duckbill valve
Of course Peggy is trying to give me advice on how not to sink my boat...
of course...
In my industry (IT), being focused on the matter at hand was priority #1.
If I am posting a specific question relating to a very specific item, I don't see the need on trying to help save my boat from my best efforts...
but all the same thanks, although I doubt all along that was the motivation.
If you read the tone of the post, including the desire to bet that my setup was not to her "standard" I think you might want to reconsider your choice.
My thoughts:
1. 50% of the message can easily be destroyed in the delivery
2. taking every opportunity to save the less learned from themselves is often not called for in this forum.
All the same, the forum is very lucky to have such a valuable resource, who is so willing and able to share her wealth and depth of information on all matters of the head.

...heading out today for a few days...saiiling to Mahahual & Xcalak, so won't have too much time to check replies, but thank you all for your assistance, advice, and opinions. I'm glad that most of us post with that understanding. No betting necessary.

cheers
Bob