Blocked heads

davel

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Over the weekend I discovered I was unable to pump out the holding tank. My arrangement is a manual pump taking waste from the tank to the outlet seacock to discharge below the waterline. The pump is not moving in exactly the same way you experience if the seacock is closed (it isn't!). As I had guests on board, I decided it best not to undertake too much investigation, however I did loosen the pipe to the inlet side of the pump sufficiently to enable air to enter the system. The pump remained immovable so I've concluded the blockage is either in the pump itself, or in the pipe downstream of the pump.

I intend to get down to the boat during the week to take a proper look and try to unblock it. The plan is to look firstly at the pump, and then move to the downstream piping where I suspect the blockage will be. I'm not looking forward to removing the pipe, which I suspect could be under a bit of pressure !

I was thinking of using one of those drain snake wires to try and unclog it. Has anyone had any experience of using one of those things on a boat? Any other ideas? Anyone fancy giving me a hand? :-)
 
You have my sympothy. The heads on my boat have blocked a few times and I finally re-plumbed the system with a macerator pump & bypass valve. Not a nice job..

Anyway a while ago their was a thread on here that may help you, I cant find it at the moment, but basically it was:

To try and clear a blockage from the outlet of the hodling tank, connect a pipe to your dinghy pump (make sure its the inflate connection).
Push the pipe up the outlet of the sea cock with the sea cock open and seal with a rag.
Then pump and the air is meant to dislodge any blockage.

I did try it and in my case it did not work as the blockage was further back, but it may work for you. I used a length of nylon compressed air pipe and drilled a hole in a wood bung to create the seal.

Hope all goes well.

I would love to give you a hand but have had more than my share of heads problems this last couple of years.
 
I suffered a solidly blocked loo right at the end of last season.
I discovered it to be caused by a wetwipe that had got passed the pump and had come to rest in the 'outbound seacock'. When we were ashore propped for the winter I managed to pull it out with one of those springy things with a plunger one end and little grabhooks at the other bought from the Portchester pound shop. Guests......Grrrrrrr!
All wetwipes are now hidden from view and polite requests made.
best of luck
S.
 
Anyone know whether it's possible to get soluble wetwipes ?

Boo2

I doubt it. The things would just disintegrate at the crucial moment. If we have guests on board that have not sailed with us before, I make a point of briefing them about heads etiquette and back that up with polite reminder notices. Our Lavac is quite forgiving but will choke up on wet wipes. Tampons and pads are easier to deal with because they get stuck in the pump and can be extracted without too much fuss or dismantling of pipework. Thankfully problems with those things are a rarity.
 
Would it be possible to disconnect the pump and refix it so it pumped back into the holding tank and perhaps dislodge whatever is blocking the outlet hose? And then turn it back round again. Sounds like a very unpleasant job (task).

Having just fitted a holding tank that hasn't been put to the test, I hate these threads :eek:
 
If you are afloat then you have little choice than to take the pump off and prod about. I had reasonable success with a bit of old stainless standing rigging found in a boat yard. If the pump has been left for a while, the pressure downstream is likely to have equalised, so you are unlikely to get that oh so pleasant spray when disconnecting the pump. Make sure your sea cock can be closed then shove in the wire. If it gets stuck, withdraw in order to see how far in the blockage is. If the wire stops at a sharp bend or joint, only prod if you are shure you are against a blockage rather than a fitting. If necessary put a short bend in the wire to get it through sharp bends. Otherwise, prod and prod and prod until you break up the offending article. Never knew what mine was as it fell out the seacock in pieces and was never seen again. We were in the Med at the time, so I was in swimming trunks when I did this with a swift exit for a refreshing swim if I got a **** shower. Here you may wish to prepare a warmer and more fragrant alternative. Good luck.
 
Thanks to all ....

... for the replies and sympathy. I'm a little dissapointed though, by the lack of offers of physical help ! :)

I'll pull on the marigolds and have a prod around :(.
 
I really don't understand why more people dont use a pedal bin for the used toilet paper/ tampax etc. This is the system we first saw on a Greek flotilla and have used every since. It doesnt smell! It's not "dirty". And there is no way on earth that a holding tank can block with just poo and pee in it.

So my suggestion is that you insist prissy visitors put bog paper in a lined pedal bin that can be emptied into the rubbish bins / skips etc every day.
 
Update

Went down to the boat yesterday. After removing the hoses (not too bad really !) I discovered the blockage is actually the stopcock which is permanently shut. The handle moves but the ball gate doesn't :( .

Looks like a lift out to replace it :( :( - Bugger!

Took the opportunity to replace the pipework whilst I was at it - ho hum !
 
You shouldn't have to lift out. You can stuff the seacock with a rag within a plastic bag to stop the seawater coming in .... and then change the seacock. Make sure the through-hull doesn't turn though, or you could break the seal. Keep a bung ready on the inside just in case. Bungs don't work too well from outside because most through-hulls have lugs on the inside in order that they can be held still during fitting.

Small seacocks can be a problem as the through-hull can break if it has corroded, but the big through-hulls for the waste should not be a problem.
 
You shouldn't have to lift out. You can stuff the seacock with a rag within a plastic bag to stop the seawater coming in .... and then change the seacock. Make sure the through-hull doesn't turn though, or you could break the seal. Keep a bung ready on the inside just in case. Bungs don't work too well from outside because most through-hulls have lugs on the inside in order that they can be held still during fitting.

Small seacocks can be a problem as the through-hull can break if it has corroded, but the big through-hulls for the waste should not be a problem.

I'm just not brave enough to try that ! The seacock itself looks badly corroded and the danger is that the through hull fitting is in a similar state.
 
I'm just not brave enough to try that ! The seacock itself looks badly corroded and the danger is that the through hull fitting is in a similar state.

Perhaps you should renew all your through hulls and seacocks at the same time ....... with marine quality ones of course. I prefer silicone bronze, although the plastic Marelon ones are good too.

Many people have said that the Ball valves are preferable to Gate valves as Gate valves tend to fail whereas ball valves don't. I do prefer ball valves ...... but they do fail, usually the spindle breaks, so you can't open or close it. I have never known the Blakes seacock to fail .... but then you don't see many about nowadays.
 
For what it's worth.
Had a problem with outlet from holding tank. Flexible wire down outlet achieved nothing.
Eventually solved (I hope) by a 20mm id bit of flexible pipe, jubilee clipped to wandering flexible pipe leading to bilge pump. Said 20mm id pipe poked down outlet pipe of holding tank.
Pumped.
At second attempt the blockage ("soluble" loo roll) came through and appeared at the bilge pump outlet.
Continued pumping until clear sea water was seen then pumped a bit more.
But what a mess .... Ah, the romance of yachting.

As a bonus, I now know that the bilge pump works (I suppose I'm lucky in that the blockage didn't block that ...).
 
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