Vacuflush losing pressure

[Merman]

For our vacuflush system I have an S series pump with a vacuum tank that is cycling every 3-4 minutes. I have replaced the pressure switch and the 4 duckbill valves. My next thought is the pump bellows, but I assume if that was cracked I'd be seeing seepage as well which I'm not. Is it possible the bellows could be the problem despite no seepage? If not, what else should I be looking at to find the source of the pressure loss?

 

[Moonfish]

We went through a similar almost complete rebuild of our Vacuflush a couple years ago. Replaced virtually everything and still it would cycle endlessly. Replaced it with a Marine Elegance and are quite happy we did. However, upon removing the old toilet I pulled the outlet hose off the back and lo and behold the hose had a hairline crack in it… Still very glad we have the ME, though!

 

[Merman]

Thanks. I'll check for cracks

 

[Comodave]

We went through a similar almost complete rebuild of our Vacuflush a couple years ago. Replaced virtually everything and still it would cycle endlessly. Replaced it with a Marine Elegance and are quite happy we did. However, upon removing the old toilet I pulled the outlet hose off the back and lo and behold the hose had a hairline crack in it… Still very glad we have the ME, though!

Yup.

 

[Ka_sea_ta]

If you are loosing pond water, check the bowl seal, if not check where the toilet base is attached to the deck.

 

[tiltrider1]

For our vacuflush system I have an S series pump with a vacuum tank that is cycling every 3-4 minutes. I have replaced the pressure switch and the 4 duckbill valves. My next thought is the pump bellows, but I assume if that was cracked I'd be seeing seepage as well which I'm not. Is it possible the bellows could be the problem despite no seepage? If not, what else should I be looking at to find the source of the pressure loss?

If it was your bellows you would see a poo trail.

Discount the hose from the head and plug it. If that stops the cycling then the issue is with the toilet and base. If it doesn’t solve the problem then you have a vacuum leak between the pump and toilet.

I always tell people to start by tightening all the hose clamps. If that doesn’t solve it then use shaving cream at all connections to identify vacuum leaks. After that disconnect from the vacuum cylinder and plug there to see which side the problem is on.

 

[Dougcole]

Same issue a couple of years ago, took me forever to run it down and cost a chucnk of change in replacing parts.


Turned out to be the "funnel" under the toilet. It had an invisible crack or leak in it somewhere. The guys at Environmental Marine (biggest vacu flush dealer in the SE) looked at it with a magnifying glass under a bright light and couldn't find a crack, but when I replaced it the vacuum leak stopped.


I personally think the PVC glue that holds on the elbow let loose a little bit.


Anyway, if you have the toilet out and the hose off I recommend you change the funnel, it's pretty easy to do and not as insanely expensive as some other VF parts.

 

[Comodave]

Ok, everyone here knows that I am not a fan of VacuFlush heads. So in all seriousness, and I am not trying to be snarky, why do you keep spending so much money and time trying to fix them? It would be cheaper and easier to replace them with a good macerating head.

 

[BruceK]

Ok, everyone here knows that I am not a fan of VacuFlush heads. So in all seriousness, and I am not trying to be snarky, why do you keep spending so much money and time trying to fix them? It would be cheaper and easier to replace them with a good macerating head.

Now now, a little respect.For some boat owners, trouble shooting and maintaining the VF is the hobby of a lifetime, a fine distraction from life`s travails.

 

[Portage_Bay]

Buy the tester!

A note to those of us who want to keep their vacuflush system alive and well.

• Buy the tester. Really. Otherwise you're just guessing. Life with a vacuflush will be much better with the tester.
• Take all 'rock solid' advice with a grain of salt. Do your own thinking and trouble shooting.
• The parts don't have to be expensive. Let Ebay be your friend.

I started a thread some time ago about vacuflush trouble shooting. The system cycled about every minute. I checked all connections, replaced diaphragm and duck bills, observed no water loss in the bowl. Tried the shaving cream test. No joy. Lots of sound advice in that thread but none of it solved the problem.

The PO had installed on/off switches at each head and we had two heads, one functioning perfectly. So use the switch and onto other more pressing old boat projects. Autopilot. Main engine fuel leaks, risers and heat exchangers. Generator control system. I could go on but you get the idea.

I found some time this spring to return to the vacuflush issue. I finally took the advice of a fellow TFer and another pro I and purchased the tester. In very short order I isolated the problem to the pump. Replaced the duck bills, it still wound not hold vacuum.

Hmm I thought. On the first round of troubles I had put a new diaphragm in. That can't be the problem. Gotta be something wrong with the pump body. I took it apart and found no obvious problems. With nothing to lose I got a spare diaphragm and O ring out of spares locker and reassembled. It has worked fine since. Holding vacuum for days when the boat is not in use. Which proves my point about taking 'rock solid' advice with a grain of salt. A failed diaphragm or O ring will not always show up as a leak. Almost always, but not this time.

 

[sunchaser]

C
We hear you (constantly) but with a bit of patience, knowledge, spare parts galore and good access VFs work fine.

I have often wondered though about the abuse our marine heads take from large bodies. A few months ago we had an ex offensive lineman onboard for a few weeks. The head survived and thanks to Art DeFever the lineman’s did too!

PS
My best source of spare parts? Free from a disgruntled dockside VF owner who swears by Tecma and hates Marine Elegance. Go figure

 

[MacPhid]

Turned out to be the "funnel" under the toilet. It had an invisible crack or leak in it somewhere. The guys at Environmental Marine (biggest vacu flush dealer in the SE) looked at it with a magnifying glass under a bright light and couldn't find a crack, but when I replaced it the vacuum leak stopped.


I personally think the PVC glue that holds on the elbow let loose a little bit.


Anyway, if you have the toilet out and the hose off I recommend you change the funnel, it's pretty easy to do and not as insanely expensive as some other VF parts.

Worked on a slip neighbours boat that had one recently, the “funnel” had an invisible crack in it that only leaked when installed. The base mounting bolts are T head, and when tightening down the toilet the “T” would twist in the funnel mounting hole and expand the plastic and open the crack. Took more than a few days to track it down[emoji15]

I agree that a vacuum gauge is indispensable when troubleshooting but I would not spend the outrageous amount vacuflush wants for theirs. I had an automotive fuel pressure/vacuum gauge in my toolbox, went to Home Depot and got a few different size rubber stoppers and drilled small holes in them to connect a hose from the gauge. Worked perfectly. Was able to verify we had good vacuum right to the base of the funnel but when the gauge was removed it wouldn’t even build vacuum even though no water loss from the bowl.

We’ve had our Marine Elegance installed on our boat for over 10 years now, this experience confirmed it was the right choice[emoji846]

James

 

[GLee]

Often over looked

One of the often over looked maintenance items for the VacuFlush toilets is the "O" rings sealing the brass flush shaft in the toilet base. I've cleaned them, re-lubricated them and done everything else only to conclude that the most robust remedy is to get the shaft kit. You can replace the duckbills until the cows come home but if the shaft "O" rigs are not sealing the vacuum pump will cycle.
Greg Lee
N5514
Roche Harbor, WA

 

[timb7734]

Had the same problem, after going through all the usual duck bill and bellows replacements, I found a crack in the pressure tank. Some Shoe Goo fixed it, never replaced the tank!

 

[RickyD]

If you are loosing pond water, check the bowl seal, if not check where the toilet base is attached to the deck.

+1 My forward toilette had a leak in the base seal. So I put in a new one. It leaked. Then my plumber said there was a base (taller) that did not have that seal. So I replaced the base and problem gone. I still love my Vacuflush. When I had smells in my aft state room due to the toilette (ultimately from the hoses ) I replaced the valves and the bellows. That was in 2018 and, knock on wood, no problems since. Oh, changing the hoses fixed the stink and I would have done it sooner but I was told the new to me boat had new hoses in the aft cabin so I tried everything else first.

 

[ranger58sb]

A note to those of us who want to keep their vacuflush system alive and well.

• Buy the tester. Really. Otherwise you're just guessing. Life with a vacuflush will be much better with the tester.

• 
  
  
  How do you use it? Where does it attach?
  
  -Chris

 

[rgano]

One of the often over looked maintenance items for the VacuFlush toilets is the "O" rings sealing the brass flush shaft in the toilet base. I've cleaned them, re-lubricated them and done everything else only to conclude that the most robust remedy is to get the shaft kit. You can replace the duckbills until the cows come home but if the shaft "O" rigs are not sealing the vacuum pump will cycle.
Greg Lee
N5514
Roche Harbor, WA

I second the nomination! Took a month of off and on troubleshooting to find this problem. No problems in five years since.

 

[ksanders]

How do you use it? Where does it attach?

-Chris

A vaccuflush tester is a handy thing to have.

it is a cone shaped soft rubber plug with a vaccum gage attached.

What you do is push it into a open hose, fitting or toilet and the suction from the vaccuflush pump pulls it in and seals.

If the pump holds pressure then the problem is further away from the pump.

for example if a vaccuflush is not holding pressure and you've tried múltiple flushes... a really easy troubleshooting method is to remove the hose from the toilet at the pump, and use the tester.

If the pump stops cycling then the problem is in the hose-toilet zone.

 

[ranger58sb]

A vaccuflush tester is a handy thing to have.

it is a cone shaped soft rubber plug with a vaccum gage attached.

What you do is push it into a open hose, fitting or toilet and the suction from the vaccuflush pump pulls it in and seals.

If the pump holds pressure then the problem is further away from the pump.

for example if a vaccuflush is not holding pressure and you've tried múltiple flushes... a really easy troubleshooting method is to remove the hose from the toilet at the pump, and use the tester.

If the pump stops cycling then the problem is in the hose-toilet zone.

Thanks for description and details!

-Chris

 

[Cartouche]

For our vacuflush system I have an S series pump with a vacuum tank that is cycling every 3-4 minutes. I have replaced the pressure switch and the 4 duckbill valves. My next thought is the pump bellows, but I assume if that was cracked I'd be seeing seepage as well which I'm not. Is it possible the bellows could be the problem despite no seepage? If not, what else should I be looking at to find the source of the pressure loss?

if water is not staying in the bowl it is the seal between the head and the base, 20 minute job

 

[OldDan1943]

if water is not staying in the bowl it is the seal between the head and the base, 20 minute job

While you are replacing that big seal, make sure you get the right side up, replace the clamshell, it may be scratch enough to prevent a proper seal. Water is getting sucked out of the bowl.

The bellows on the pump might be leaking, replace it. While you have the head apart, replace the duck valves.

Assuming you have done the above and it still wont shut off, remember there is a vacuum control switch too. Exercise this valve and if necessary and you cannot adjust it, replace it. You may have to adjust the new valve too.

 

[Dougcole]

A tip if you don’t have a vacuum tester is to use a cone shaped cedar plug, the kind designed to go into a through hull in an emergency. Get it really wet, then use it in the same way as the tester. Not quite as good as the tester, but it does work at a fraction of the cost.