Maxi 1100 blocked heads

smallplasticboat

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On a friend's 1100 with a total blockage somewhere between the jabsco manual pump (after the Joker and elbow) and - presumably - the holding tank.

The exit hose is maybe 50mm external but is almost completely blocked by rigid (& friable) limescale deposits. Presumably urea related. I've cleared the accessible few inches at the toilet end, but no luck with any through flow yet.

Accessing the tank and that end of the pipe (and presumably a U bend?) is next. Any advice from readers with experience of this problem, before we start stripping put the cupboard beside the heads? We are stuck in a mid river mooring so limited access to shoreside facilities here!

Thanks
 
Easiest and cheapest way of dealing with limescale is to remove the pipework and belt with a hammer or against the quay. Flush through and refit. As you are on a mooring take care not to throw any parts overboard, as I have done, much to SWMBO's annoyance!
 
Mechanical methods are the only practical way. Hydrochloric acid will clear it eventually but you would need a great deal of it and it is almost impossible to get it where it needs to be. Hammering the hose in situ might help but removal is the only way to do it properly.
 
Apart from a blocked pipe between the jabsco and the tank have you considered possibility of blockage eg waste put down heads such as excess paper between tank and exit to sea as another possible cause ? It’s just you say presumably holding tank,hence enquiry. I suppose if removal is dramatic you could take boat to a marina which has holding tank pump out suction and suck out the tank via the deck filler?that won’t fix your pipe blocked by deposits but might be a simple first solution if you have a suitable marina nearby. Do you have a diagram of the pipe arrangements and also an owners association might be another source of advice?
 
It is likely that replacing the pipe, if this is scaled, will entail little more work than unblocking it mechanically, and dismantling will in any case be necessary. A friend found that the blockage on his boat was from a kitchen wipe, a legacy from a previous owner. My only advice is to ensure that the task is undertaken by someone else.
 
It is likely that replacing the pipe, if this is scaled, will entail little more work than unblocking it mechanically, and dismantling will in any case be necessary. A friend found that the blockage on his boat was from a kitchen wipe, a legacy from a previous owner. My only advice is to ensure that the task is undertaken by someone else.


We had similar blockage on our owners cabin en suite heads and eventual solution involved firstly a lift out and replacement of seized seacocks/skin fittings,plus the replacement of ALL hoses which on discharge side were down to about 20mm bore. We included a revamp of pipework to install a changeover valve for optional direct discharge overboard when legal and appropriate and also swapped out the twist n'lock pump for a new one. Oh and we took the advice to have someone else do the job, in our case the excellent on site engineers. Seacock/skin fittings removal alone took many hours.
 
When mine blocked, some years ago, it was going to involve major surgery to replace the hose. However, by disconnecting at a couple of diverter valves, I eventually managed to get one of these Lidl/Aldi flexible wire rotating pipe cleaner things through the blockage. Brick cleaner, containing hydrochloric acid, was then able to work on the encrustation in the hose.
Jabsco recommend a minimum of seven strokes of the pump per metre of outlet hose. In our case, that involves a minimum of 40 strokes, which is a pain, but has ensured that the pipework remains perfectly clear.
 
When mine blocked, some years ago, it was going to involve major surgery to replace the hose. However, by disconnecting at a couple of diverter valves, I eventually managed to get one of these Lidl/Aldi flexible wire rotating pipe cleaner things through the blockage. Brick cleaner, containing hydrochloric acid, was then able to work on the encrustation in the hose.
Jabsco recommend a minimum of seven strokes of the pump per metre of outlet hose. In our case, that involves a minimum of 40 strokes, which is a pain, but has ensured that the pipework remains perfectly clear.
The problem with pumping large volumes of water is that the holding tank fills very quickly. Our biggest problem with the Jabsco Lite was that in order to avoid filling the tank, Jabsco cut down the flush rate to the absolute minimum and make a point of advertising this feature. Consequently, as liveaboards we constantly battled fouling of the macerator impeller, joker valve and discharge hoses, as well as the tank itself.
 
When mine blocked, some years ago, it was going to involve major surgery to replace the hose. However, by disconnecting at a couple of diverter valves, I eventually managed to get one of these Lidl/Aldi flexible wire rotating pipe cleaner things through the blockage. Brick cleaner, containing hydrochloric acid, was then able to work on the encrustation in the hose.
Jabsco recommend a minimum of seven strokes of the pump per metre of outlet hose. In our case, that involves a minimum of 40 strokes, which is a pain, but has ensured that the pipework remains perfectly clear.
too many fingers for (some) ladies to count in my experience... :eek:
 
The problem with pumping large volumes of water is that the holding tank fills very quickly. Our biggest problem with the Jabsco Lite was that in order to avoid filling the tank, Jabsco cut down the flush rate to the absolute minimum and make a point of advertising this feature. Consequently, as liveaboards we constantly battled fouling of the macerator impeller, joker valve and discharge hoses, as well as the tank itself.
It has always seemed unsatisfactory to me to have the holding tank as an unavoidable part of the waste pipe. In our case, the gravity-draining tank is only in use when needed and the rest of the pipework can be flushed as much as we want, even when the tank is part full. I realise that larger boats with more complex systems have their own constraints, but it still seems odd to me.
 
It has always seemed unsatisfactory to me to have the holding tank as an unavoidable part of the waste pipe. In our case, the gravity-draining tank is only in use when needed and the rest of the pipework can be flushed as much as we want, even when the tank is part full. I realise that larger boats with more complex systems have their own constraints, but it still seems odd to me.
The heads compartment in our boat is so constrained that there is simply no space to put a diverter valve or a second seacock. Plus the double skin makes such additions complex .
 
It has always seemed unsatisfactory to me to have the holding tank as an unavoidable part of the waste pipe. In our case, the gravity-draining tank is only in use when needed and the rest of the pipework can be flushed as much as we want, even when the tank is part full. I realise that larger boats with more complex systems have their own constraints, but it still seems odd to me.
Simplicity and cheapness. The factory fit holding tank on my first Bavaria was the pump type with diverter valves and its own tank and outlet, located on the opposite side of the boat with 5m of hose running under the saloon floor. Needless to say we did not specify this option as you can imagine what a mess (literally) charterers would have made of that. We subsequently managed to squeeze in a 45l gravity tank when the boat was retired from chartering. As Vyv says many older boats do not have space to fit a good system, and even modern boats with shallow bilges have difficulty in finding space for a pumped system, but wide beam allows space to fit a decent size (60l on my later Bavaria) under the side deck with decent accessibility to all the pipework.
 
The problem with pumping large volumes of water is that the holding tank fills very quickly. Our biggest problem with the Jabsco Lite was that in order to avoid filling the tank, Jabsco cut down the flush rate to the absolute minimum and make a point of advertising this feature. Consequently, as liveaboards we constantly battled fouling of the macerator impeller, joker valve and discharge hoses, as well as the tank itself.
Fair enough.
Where we sail, there is almost never any need to use the holding tank. The method of clearing a blockage is still relevant - maybe frequent dosing with brick cleaner is called for, if pumping into a holding tank.
 
Simplicity and cheapness. The factory fit holding tank on my first Bavaria was the pump type with diverter valves and its own tank and outlet, located on the opposite side of the boat with 5m of hose running under the saloon floor. Needless to say we did not specify this option as you can imagine what a mess (literally) charterers would have made of that. We subsequently managed to squeeze in a 45l gravity tank when the boat was retired from chartering. As Vyv says many older boats do not have space to fit a good system, and even modern boats with shallow bilges have difficulty in finding space for a pumped system, but wide beam allows space to fit a decent size (60l on my later Bavaria) under the side deck with decent accessibility to all the pipework.
Yes. As I implied, there are reasons for a through system on some boats, but I still think of it as a second-best option. We have a 60l tank on a 34' boat via a diverter, and I have always wondered why they couldn't fit a similar tank or tanks into my friend's vast 46' Island Packet. The result of a blockage can be quite troublesome when the only pump-out has to come from through the harbour office.

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Thanks for all your thoughts.

In the end, we wrapped each end of the 38mm ID tube with polythene, taped that on and removed the 4 foot of tube without too much problem. Then beat it with a mallet, flushing the calcium chunks (and feces) out regularly over the stern. It went back in easily and without mousing, and job done.

Next is to figure how many strokes of the pump it takes to clear out the tube entirely (which I make about 1.5 litres - yet to find the pump bore and stroke??) and what form and quantity of acid to flush into it to prevent any recurrence.

Happy to receive any views on those two issues.
 
Thanks for all your thoughts.

In the end, we wrapped each end of the 38mm ID tube with polythene, taped that on and removed the 4 foot of tube without too much problem. Then beat it with a mallet, flushing the calcium chunks (and feces) out regularly over the stern. It went back in easily and without mousing, and job done.

Next is to figure how many strokes of the pump it takes to clear out the tube entirely (which I make about 1.5 litres - yet to find the pump bore and stroke??) and what form and quantity of acid to flush into it to prevent any recurrence.

Happy to receive any views on those two issues.
You could try reading #9.
 
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