Head Fill Height Issue

[JLR]

I have run into an issue on one of the heads on my 74 MY. The head is a galleymaid, raw water fed head with the Delta green button timed flush. The problem is that the head flushes normally and appears to refill normally. However, although the water refill appears to stop, a few hours later, the head has refilled to within one to two inches of the top of the bowl. Any suggestions?

 

[Boatnut]

Sounds like you need to watch the bowl, and determine if the unit is recycling by fault of the pump circuit, or you have a leaking valve in the system. Thats if the water is clean, if dirty then you may have a bad joker valve.

 

[JLR]

Where is the joker valve in the system?

 

[SeaEric]

Is this head below the waterline?

 

[JLR]

I believe so. I also think it is likely filling to the water line.

 

[MikeP]

Yes, that is exactly what is happening, it is filling to the boat's water line. I have had that happen twice and, in both cases, new stators in the pumps corrected it. There are no joker valves in the GM system. As the stator/rotor clearances increase over a lot of use, it will allow back flow due to syphoning. Fortunately, at least in the case of the 53MY, the top of the bowl is above the water line so it can't overflow when sitting at the dock or at anchor under normal conditions. But it could spill over if the boat is rolling and then continue to fill back to the water line level, roll, spill again, refill...etc.

Another way to absolutely and permanently correct it is to install vented loops in the discharge and intake lines. These are shown in virtually all below-water-line head installation instructions though Hatteras does not seem to have ever used them with the GM heads.

But new stators should fix the problem unless the rotor is badly worn/pitted. In that case, both the stator and rotor need to be replaced. Usually the rotors are fine which is fortunate since they don't give them away!

RAZ marine has all the parts and any expertise you might need - http://razmarinepumps.com/marine-toilet-head-water-pumps/raz-marine-pump-parts.html

 

[JLR]

Thanks Mike. I needed to call Razz about something else as well.

 

[JLR]

I just spoke with the folks at Raz. They are always very helpful. They suggest a problem with the vented loop. I also bought two discharge stators just in case the vented loop was not the problem. Now to find out where Hatteras places the vented loop?

 

[JLR]

Well, they say it never happens but it appears to have done so. The back filling of my head appears to have stopped after I flushed the head for 30 seconds or so. My guess is a clog in the discharge line either permitted the discharge stator to remain open in some fashion or a clog prevented the vented loop (if I have one) from opening properly. I hope it is just that simple.

 

[MikeP]

"Well, they say it never happens but it appears to have done so. The back filling of my head appears to have stopped after I flushed the head for 30 seconds or so."

That's possible. However, when that problem occurred for me it was somewhat random - sometimes it would back fill, sometimes it would not. See how it acts for "normal" flushes for the next few days.

Re vented loops - the GM head paperwork/installation instructions/operator instructions that were supplied with our 1980 53MY describe the installation of vented loops and the fact that they need to be present as part of the installation. Hatteras obviously disagreed since they did not install vented loops on any of them. Go figure...

 

[JLR]

Of course, our summer trip is set for four weeks and I would love to know whether I have a problem in the head or not before then. Isn't that the way it often goes.

 

[Angela]

Well, they say it never happens but it appears to have done so. The back filling of my head appears to have stopped after I flushed the head for 30 seconds or so. My guess is a clog in the discharge line either permitted the discharge stator to remain open in some fashion or a clog prevented the vented loop (if I have one) from opening properly. I hope it is just that simple.

My master stateroom head did that, too. The filling fairy WILL return. I never could figure it out or fix it. It only did it on that one head. Using drops of food color to watch the "current" in the bowl, I did figure out that the water was coming in from the bottom of the bowl and not from the supply side of the system. I got tired of chasing the gremlin and replaced the whole thing with a Vacuflush. Good luck. I couldn't fix mine.

 

[JLR]

Thanks. Mine also fills from the bottom. I guess I might just replace the stator hoping never to see a return again.

 

[JLR]

Well Ang, as predicted, the fairy did return. Bowl still filling over time from the bottom. I hope changing the discharge stator will do it. No place to even install a vented loop and could not find one previously installed.

 

[JLR]

Update - changed the stator and the problem is not fixed -- it is still intermittent. Local mechanic found what he though might be a one way valve in the discharge line. We will replace that as well as add a vented loop and that should be belt and suspenders for fixing this issue--at least I hope so. Now, on to finding fittings which were used to turn my other salt water heads into fresh water heads. One of the heads has a fresh water leak at the fitting.

 

[MikeP]

"Local mechanic found what he though might be a one way valve in the discharge line. "

If there is one, it was added by somebody. They are not part of the normal installation. It sounds as if the problem has been a longstanding one and perhaps a PO installed a check valve in an effort to eliminate it. I suppose it would help but it adds a restriction/possible obstruction to the flow over time.

Does your head pump have a small copper tube mounted on it that goes from the intake pump side over to the discharge pump? Older pumps had those to ensure proper priming but they were eliminated later because they often caused what you are describing. If that tube is present, remove it/cap the fittings.

Is this head dumping into a holding tank? IF so then the only liquid that could back flow is whatever is in the discharge line above the head's S trap. Once the liquid is dumped in the tank, it is impossible for it to flow back out via the discharge fitting. Is the water filling the head clean? (from the input side) or is it backflow from the waste side?.

 

[JLR]

I do not believe I have the copper line you describe - or any at all. Also, no doubt the pump was moved to make room for the bow thruster taken off of the starboard engine. The discharge side is currently set up to go other than in the holding tank, but of course the head is not used unless outside of colregs. It is filling, when it does fill, from the bottom of the bowl and is filling with sea water. Mike - I leave it to you to recall the color of that water from Huntington Harbor.

 

[MikeP]

"Mike - I leave it to you to recall the color of that water from Huntington Harbor."

LOL, good one!

Well, a functioning check valve should stop it and a vented loop certainly will. Obviously, I believed that a new stator would take care of the problem since it has worked for me that way on several occasions. The only problem with a vented loop is that they can vent some odor into the boat when the valve opens unless a hose is run off the vent fitting to a location outside the boat.

It's interesting that RAZ sells a vented loop for these heads but Galley Maid does not.

Personally, with the head still back-filling after a new stator was installed, I would remove the check valve (if there is one) and install the vented loop. But it would be interesting to understand why a new stator seems able to correct the problem sometimes but not others. It's totally a function of the water-tightness of the rotor/stator interface so one would think that a new stator would solve the problem as long as the rotor is clean/all rubber deposits removed upon reassembly.

I guess some things are beyond human understanding!

Good Luck!

 

[JLR]

Thanks Mike. I'll provide another update when all is resolved -- hopefully.

 

[mr hatt]

hey guys. I've had the same issue for a couple years. I swapped out the discharge stator and installed vented loops, but no luck. maybe I'll try replacing the intake and discharge stators. I also have a check valve installed. I also tried different combinations with the crossover tubes. it's the middle head on our 58 yachtfish and it's a raw water system with a raritan msd.