Toilet flush problem

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Anita

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The water inlet isn't working on our Jabsco manual toilet. The contents are pumping out, but no seawater is coming in. Have taken the pump apart and replaced all parts, but no luck. Suspect we may have a blockage? Any tips on how to check/treat while in the water?
 
If its a vacuum job - it maybe stating the obvious - but have you double checked the seal on the seat / lid.

Only mention it because having stripped my pump and serviced it (twice!) a couple of weeks back - eventually discovered the seal had come adrift from the seat - wasn't even torn /forums/images/graemlins/crazy.gif - symptoms were exactly the same as yours..

Otherwise - double check (perhaps by blowing down - somehow ..??) that the water in pipe isn't blocked.

Oh well - I'll know for next time ....

Good luck
 
I have had this prolem with a similar toilet in the past. The only way i manage to unblock it was by swimming under the boat and removing build up around inlet. Never nice, especially as the water is still cold at the moment, but it is cheaper than having the boat lifted. In my case it was due to the build up of barnacles etc.

You could try disconnecting the inlet at the toilet end and pumping air back through, but you need to make sure you can lift pipe above the water line. If you dont you will find you boat filling with water.

Good luck
 
If, and only if, you are confident about the inlet seacock take the inlet pipe off the at the loo end and cautiously open the seacock and see if you get water coming through when the open end is below the waterline. If yes the the problem lies with the loo if no try again with the pipe off the seacock. That will eliminate or confirm a blocked hose. If you still do not get water through check that nothing is lodged in the hose tail of the seacock. The inlet seacock will probably have a strainer grill on the outside so if you have got this far without finding a blockage the next step is to dry out and take a look at that. They can get blocked with many coats of A/F and a few bits of debris so should always be cleared before launching. If you know there is a grill there then go for that first as nothing should get through it to caues a blockage elsewhere

I have assumed that you have a proper seacock rather than a gate valve which has come apart internally and that it is in the open position when you think it is.
 
If it's being caused by a blockage, the pump would be near impossible to to push/pull (when in the flush position). When you say that you've replaced all the pump parts, have you also replaced the rubber gasket that has the two flapper valves in it? We discovered that the valve that's held open when the lever is in the dry flush position quickly becomes permanently distorted, so that when you select wet flush it doesn't seal, therefore, no flush - the normal pump out still works.

When this happened on our loo, being only six months old and subjected to fairly light use, I refused to accept that it needed a service kit. Instead, the gasket was removed and soaked in boiling water with various crocodile clips holding the valve in such a position to correct the 'misalignment'. Result, one working thunderbox! As I mentioned in a previous thread a few months ago, I believe there is a fundamental design flaw in the Jabsco toilets. Although they recommend leaving the loo in the dry flush position, I have found that the only way to ensure continued reliable operation is to leave it in the wet flush position and shut the inlet seacock between each 'visit'.
 
Have you tried this?

1. Ensure inlet stopcock is closed.
2. Disconnect the inlet stopcock from the toilet/pump
3. Connect a spare piece of pipe to the toilet/pump and place the other end into a bucket of water.
4. Pump - If the water is being sucked out of the bucket you know the pump mechanism is fine and you have an inlet blockage/stopcock problem. Should the pump not work I'm afraid you'll need to check all those pump components.

With regards to a blockage, depending on where you sail try and find some drying out posts you can moor up to. When the tide drops you can inspect the inlet and determine whether it's a blockage or a stop cock failure (You've switched to open however, the valve stays firmly closed).

Much safer way to check inlets, no lifting required and a lot less risky than popping over the side.

Hope it helps.

Oh yes and remember heads problems are always character building /forums/images/graemlins/smile.gif IMO it's the worst job on the boat, deal with that and you can deal with anything /forums/images/graemlins/smile.gif (A season or two ago I had to change all seals on the heads in the heat of summer when they failed horrible, horrible job!).
 
One thought is that there are two ways of plumbing these. Conventional wisdom has often been to have a syphon breaker loop in the inlet pipe, between the sea cock and the pump. Jabsco now recommend that the syphon breaker is placed between the pump delivery and the bowl. This is to improve suction.

If you have a syphon breaker/high loop on the suction side of your pump, ie between pump and seacock, this may be a problem.
 
Thanks to everyone for some great advice! We will spend tomorrow jammed in the heads experimenting....other half says he can't wait!

Anita
 
I have cleared a block inlet and pipe by connecting a water hose to it. Be careful to make sure you dont blow fittings apart if they are old and got galvanic problems. No coppery look to them?
 
[ QUOTE ]
The water inlet isn't working on our Jabsco manual toilet. The contents are pumping out, but no seawater is coming in. Have taken the pump apart and replaced all parts, but no luck. Suspect we may have a blockage? Any tips on how to check/treat while in the water?

[/ QUOTE ]

Unless a sea critter has set up housekeeping on the intake thru-hull, it's unlikely you have a blockage. More likely, there are only three probable causes:

1. Every spring at least half the posts and emails concerning Jabsco toilets are asking why it won't bring in flush water any more. And 90% of the time, it's because the boat was stored for the winter with the toilet in the "dry" mode, which causes the rubber in the flap valve to distort and pucker. Replacing the flap valve didn't fix it because you either put it in backward--which is very easy to do--or didn't seat it correctly.

2. The wet/dry "cam" in the pump has gotten hung up in the "dry" position--a VERY common problem in Jabsco toilets made in the last 5-7 years due to a design or tooling defect...and they don't seem to be inclined to correct it. That part is not in the service kit, so replacing all the bits in the kit won't cure it.

3. Or, any vented loop in the intake is in the wrong place--between the thru-hull and the pump, which won't let the toilet prime. It belongs between the pump and the bowl...to replace the short piece of hose the mfr uses to connect 'em. This doesn't represent any change in "conventional wisdom" or Jabsco recommendations, only a lack of understanding by most boat owners about how a vented loop works and where to put it. If that is your problem, you can find out very easily: put your finger over the hole in the top of the vented loop and pump the toilet. If it still won't prime, that's not the cause of your problem.
 
Have had the same thing happen to day,seems like the inlet was blocked.The fix was to undo the six screws on top of the pump and poor a cup of water into the pump houseing but on top of the plunger.
 
Headmistress

My point with regard to conventional wisdom, and practice was sound.

Some boat manufacturers in the UK, installed as original fit, siphon breaker loops, without vented loops, which were deemed unnecessary if the intake and discharge hoses looped sufficiently high above the waterline. That was a conventional arrangement, and meant that the pump had to overcome the suction head imposed by the extended loop in the flush water intake. It worked, although it was sometimes necessary to prime the system, as you describe, using a thumb over the flush water port. My boat circa 2003, was supplied with this setup..

Jabsco recommend the system you describe, ie that the flush water intake hose is not looped, and a loop is installed in the flush water hose, between the pump and the bowl. Some boat builders who formerly placed high unvented loops between the intake and the pump now comply with the Jabsco recommendation.

While I am loath to make a general case based on incomplete data, there has been a change, for some classes at least, in conventional wisdom. Because we do not know the configuration of the installation that was causing problems, this consideration was relevant, especially if there has, due to replacement or deterioration been a reduction in the suction head developed by the pump.
 
[ QUOTE ]
Jabsco recommend the system you describe, ie that the flush water intake hose is not looped, and a loop is installed in the flush water hose, between the pump and the bowl. Some boat builders who formerly placed high unvented loops between the intake and the pump now comply with the Jabsco recommendation.

While I am loath to make a general case based on incomplete data, there has been a change, for some classes at least, in conventional wisdom.

[/ QUOTE ]
So Bavaria did not take a short cut with my late 2004 manufactured yacht.

Currently I have zero suction on the inlet of my Jabsco toilet. I had assumed the straight run from toilet to inlet seacock caused the pipe to run dry and the proper solution was a looped inlet pipe. Now I am not so sure, it seems as though I should try the rubber value in boiling water remedy first.
 
The problem with an unvented loop in the intake is, priming the pump starts a siphon. So an unvented loop isn't much help. However, neither is a vented loop between the thruhull and the pump, because there it does break a siphon, but also prevents the pump from priming. So the ONLY place an intake loop belongs is in the line between the pump and bowl. It works there because the pump pulls water from the thru-hull, then PUSHES it into the bowl...a siphon break won't interfere with water being pushed through a line.

It's not so much a change in conventional wisdom--the laws of physics haven't changed...but finally understanding how the d'd things work.

Many people are still in the dark about the need for an air valve--a one-way valve that only allow air in, nothing out--in a vented loop in a line through which water or waste is being pushed. They think that little threaded hole in the nipple at the top of loop is the only vent. So they think there are only two solutions to water/waste squirting out of that hole--hold a finger over it while pumping, or put a tube on it. While holding a finger on the hole while pumping a toilet is a bit of PITA, it's actually a far better solution than putting a tube on it...'cuz the tubing is so small that sea water minerals and/or waste quickly block it...turning the vented loop into an UNvented loop that no longer has ability to break a siphon...something that rarely if ever occurs to anyone because it's an "out of sight, out of mind" issue. It apparently never occurs to many boat builders, yards, authors of maintenance books and even marine sanitation equipment mfrs, 'cuz a lot of 'em recommend it. However, the RIGHT solution is an air valve in the loop...and they require periodic cleaning and replacement.
 
To be clear, I dont argue that the correct place for the flush water loop is between the pump and the bowl - only that some builders have (somewhat dubiously) put the anti-syphon loop between the seacock and the pump.

Incidentally, I replaced the head supplied with the boat with a Jabsco, after two pump barrel failures that would not have been protected by a loop between the pump and the bowl. Personal preference is to keep the seacocks closed at sea.
 
You've raised an interesting issue. A vented loop will break a siphon and create a "hill" in the line above the waterline that prevents water outside the boat from finding its own level INside the boat passively, when the boat is at rest...but it cannot prevent water from being pushed through a line--an effect known as "ram water"--from being pushed over the top of it and into the bowl.

And that's what often happens while underway on the same tack as an open intake or discharge thru-hull...the pressure of the hull against the water (or the water against the hull...I've forgotten the exact physics of it) as the boat moves through the water forces water up an open thru-hull. I've been on boats myself on which the intake thru-hull was left open and the toilet in the "wet" mode and seen it happen.

Oddly, it doesn't happen all the time...on some boats it never happens. When or whether it happens depends on a combination of sea conditions, angle of heel, and precise location of the thru-hull. But if you do experience it, the ONLY solution to it is, as you're doing: keep the seacocks closed except when in use. Or, if they're so inaccessible as to make that impractical (regrettably all too common on many boats built today because decor now trumps safety, and seacocks cannot be considered "decor" items), a shut-off valve in the line that is accessible. The only alternative is to keep the mop handy.
 
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