Jabsco Heads - no flush

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NFCN

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I'm sure this has happened to someone out there.

The heads have been working fine for 2 seasons, and this weekend despite pumping I've been unable to bring water in to the bowl (standard Jabsco arrangement, lever switched left). There's no blockage on the way out - a bowl of water in the bowl and it'll flush out ok, so it sort of works.

Seacocks all fine and definitely open. My guess is either the valve is dodgy or the there's a blockage near the skin fitting.

Can anyone help?

Many thanks.
 
Easy to check for a blockage. Disconnect the inlet hose to the unit, open the seacock and water should pour in through the hose.

If the trouble is with the pump assembly, it is an easy job to overhaul it. You can buy an overhaul kit at a chandlers. There are two kits available. Which to use depends on the age of your heads, as identified by the colour of the pump handle. Or you can buy a complete new pump asssemby.
 
We had a similar problem early this season which seemed to relate to an air lock on the intake side. No amount of pumping would draw water in but water would be readily pumped out. The problem was 'cured' by pumping when the boat was healed hard to port (heads are on the port side) - this reduced the lift height required. It has worked perfectly under all conditions since!
 
You can get scale in the pump cylinder. Fill the bowl with fresh water (or salt, come to that) and add a good teacup of fuming hydrochloric. Pump out slowly, over a couple of minutes, allowing the acid to work. When the bowl is nearly empty, pour a couple of tablespoons of oil - (we save old cooking oil in a Harpic toilet cleaner bottle for this) and pump until the oil is down at the very bottom. You might need to add a couple of cups of water and pump to get the oil up into the cylinder. You have now hopefully got a scale-free and lubricated cylinder which should pump water in unless you have a blockage somewhere.

Urine, when it breaks down over some hours, produces ammonia. The ammonia precipitates out calcium in the seawater. That's what causes the scale in toilet pipes. We find that using hydrochloric acid regularly as described above keeps everything fine. We have been living aboard since August 2004 and never had to remove the toilet pipes for descaling. I do ours a couple of times a month.
 
exactly how we keep our three Jabscos scale free, you musty have told me some time ago, been doing it for the last ten years, never (touch wood) had a problem with scaling. Service wen needed, thats all, if you have two toilets, I would reccomend, having a spare pump assembly, quick to change, then repair/service spare, when convenient.
 
It may just be a bit of scale or crud in the flap valve at the top end of the pump. I'd take the top of the pump, clean the rubber flap valve and seating and re-assemble. Sometimes after being heeled over there is no water in the pipe so a vigorous pumping half a dozen strokes does the job. Try the simple and free things before spending half the price of a new loo on a service kit.
 
My father, who lived aboard from 1972 to 1996, came up with the hydrochloric trick a couple of years after he started, having decided that banging toilet hose on the dockside was not fun! I have carried on the fine tradition. Trouble in the UK is that they think you want to dissolve granny in the bathtub if you ask for concentrated HCl whereas you can buy 5 litres in Mercadona for a few Euros.
 
A common problem on Jabsco bogs. Usually cased by the flappy lump of rubber that is pushed up when you want to pump the bowl dry. Have you left the lever in the 'dry' position? If so, that bit of rubber is bent upwards by the lever, and unfortunately likes to stay that way.

The solution...

1) Put the lever in the wet positon and wait a while until that bit of rubber slowly loses its upward bend and will seal again. May take half a day.

2) After pumping out with the lever in the dry position, return the lever to the wet position before departing.

That bit of rubber may be permanently bent and require replacing, which is where you hit Jabso loo problem number two - the self tapper plastic splitting problem.

They are crap bogs.
 
Hi

I used to have this problem on my old boat. In my case this was due to an airlock in the inlet hose, probably caused by wear on the intake/pump valve, allowing air to creep into the hose when the toilet was not used between between weekends. The result was a lot of pumping but no water, only air being displaced (you feel it in the pump, it is too "light" when pumping. )

The unfortunate more permanent solution is to do a service of the pump assembly. I did this on my new boat recently and apart from being a little unpleasant when the discharge hose is taken off, it is fairly straightforward. (even if the diagrams are a little scary)

An interim solution, that I managed to keep working for quite a while was to try the following:
1) try pumping really fast for a short period of time to displace the airlock (usually about 20 30 strokes very quickly) and prime the pump.
2) If that doesn't work, take off the water inlet hose <span style="color:red"> from the bowl end</span> i.e the hose that runs from the pump to the top of the bowl (which on my boat did not have hose clamps as it was protected by the pump), hold your thumb on the end of the hose and pump. This creates pressure and should break the airlock. Downside is that there is usually some water coming out at high pressure into the heads, so be careful where you point that hose /forums/images/graemlins/tongue.gif.

The second option was pretty quick and always worked for me, but did not half spoil a friday evening after a few pints at the pub.

Hope this helps

Tom
 
Service kit.

After 3 years the pump needed servicing but when I found out the service kit was £30something and a whole new assembly was only £50something it seemed a no brainer to replace the whole thing and not worry about the self tapper into plastic problem.
 
Self tappers into plastic solution, when they strip, which they eventually will, no matter how gentle you are, clean out hole, fill with epoxy, drill pilot hole, refit self tapper, just save yourself about 50 squid! I think all of my loos have this "modification".
O forgot, doint use jabsco self tappers, they are "two start" screws (double thread) and strip easier than standard ones, oh! and another thing, use proper self tappers with coarse threads.
This is the benefit of years of bog repairing!
 
Thanks everyone. Will try the acid test, rapid pumping, disconnect & pump then servicing advice in that order.

Anyone know where I can get hold of a small quantity of decent hydrochloric acid without being arrested?

Nick
 
It is often the little flappy thing with the brass coin attached to it.I serviced mine last year with the complete kit but had to replace the flappy bit as it had deformed.This bit you can buy separately for about5/6 pounds.If you have a more modern Jabsco this kit also has the little spring you need.I was told to stretch it a bit before fitting it(the spring that is) .I am going to get the lock & twist pump when boat show offers come along
 
Brick cleaners are often hydrochloric acid. (but twisted owner has already said that)

By comparison Rydlyme from many chandlers will be expensive but should be just the stuff to use.
 
Robert Dyas used to sell HCl but kept it behind the counter (worried that the kiddies were going to sniff it, I wouldn't wonder /forums/images/graemlins/wink.gif)
 
Had a "no flush " situation removed piston and found that "0" ring on plunger was broken €2 to replace.Now working.
If this does not solve it buy a service kit and replace everything about £30.
 
Headmistress - instructions

The life expectancy of Jabsco toilets made in the last 7-8 years is only about 2-5 years before something fails.

Dave, yours blew a breaker because somebody flushed something they shouldn't have...it's clogged the macerator and discharge pump impeller. When they can't move, the motor overheats...the breaker blows. Take it apart, clear out the clog, and it should work again. And then instruct your guests that NOTHING they haven't eaten first except a maximum of about 5 sheets of quick-dissolve TP is to go down the toilet. And always flush long enough to move the bowl contents all the way through the system...don't stop the second the bowl is empty.

Joanne...you may have pulled in a weed, but I doubt that's what's caused your problem...I'm betting it's a failed wet/dry valve--a VERY common problem in Jabsco toilets made in the last 5-6 years. The actual valve is just a little "gate"...the lever swings it to block off or unblock the flow of flush water. Due to either a design or tooling defect, that little "gate" hangs--almost always in the "dry" mode, preventing any flush water from coming in...and when it hangs, it also creates backpressure that's easy to mistake for a clog. Jiggling the wet/dry lever MAY free it up, but only temporarily...it'll hang again. The only cure is a replacement wet/dry valve assembly...or better yet, a higher quality more reliable toilet.

But you still need to clear out the vegetable life...and that's likely to be a bit messy..but you can minimize the mess. First, close the intake seacock. Pump your toilet as dry as possible. Put a pan or plastic bag under the hose connections before removing them. Disconnect the intake hose from the toilet and the seacock...check the thru-hull for anything that may be caught in it...put the hose on the dock and blow it out with water. Remove the top of the pump...depending on the age of your toilet, that may require removing 6 screws, or only loosening a hex nut. Carefully pull up the pump handle to check for any material in the pump. If there is any, remove the pump piston altogther and clean it out. I'd have an exploded drawing of the pump assembly handy so you can make sure all the bits go back where they belong, oriented in the right direction...if you don't have one, it's here: http://www.jabsco.com/prodInfo/overview/29090-2000_ev.pdf

While you have the pump open is a good time to lubricate it. Buy a tube of synthetic teflon grease...put a HEALTHY squirt of it into the cylinder...pump a few times to spread it all over the inside of the cylinder...replace the top on the pump.

As for cleaning your toilet: do NOT use any household chemical bowl cleaners, bleach, or household cleaning products containing bleach, pine oil, or "antibacterial" cleaners. Wipe out the bowl with little liquid or powdered cleanser on a sponge or paper towel...flush a cupful of white vineger down it in the dry mode.

Ok, class...any questions? /forums/images/graemlins/smile.gif
--------------------------------------------------------------------------------
Peggie Hall
Specializing in marine sanitation since 1987
 
Re: Headmistress - instructions

Maybe add instructions about what to do after he has stripped the threads? See Englander's post above!
 
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