Poo pipe part 2

[Addem 95]

Another poo pipe question unrelated to Parnell.

I have a head where the outlet pipe is built in under the floor. It's a fixed floor as is also the shower. 

The pipe is nearly level and over decades (2005 construction) poo et al  has been sitting and doing something to the pipe. It is now seriously blocked through some sort of scale/plaque/calcification  (I know it is not calcium but you get the idea).  The plaque is like a plaster lining and is now blocked solid. Can't get a wire etc through. 

We've tried unblocking with all sorts of machinery but think we have compacted it. 

Last roll of the dice before saws are called to action is whether some chemical can be used to break it down. 

Any ideas? Experience?

[dutyfree 170]

My experience is that it is like concrete.  Had a plumber come with normal drain unblocking equipment and could not get through it. We pulled the piping out, I could jump on it on the dock and not break it.

You could try white vinegar and just leave it to see if you can dissolve it a bit.

Once you fix it, always flush through with fresh water before you leave it moored, occasionally leave white vinegar in there too.

[K4309 260]

43 minutes ago, Addem said:

Another poo pipe question unrelated to Parnell.

I have a head where the outlet pipe is built in under the floor. It's a fixed floor as is also the shower. 

The pipe is nearly level and over decades (2005 construction) poo et al  has been sitting and doing something to the pipe. It is now seriously blocked through some sort of scale/plaque/calcification  (I know it is not calcium but you get the idea).  The plaque is like a plaster lining and is now blocked solid. Can't get a wire etc through. 

We've tried unblocking with all sorts of machinery but think we have compacted it. 

Last roll of the dice before saws are called to action is whether some chemical can be used to break it down. 

Any ideas? Experience?

I don't recall the chemistry of your stuff in the waste pipe, but if you are desperate for a solution you could try a heat exchanger cleaner. They get the same sea-salt encrustations of heat exchangers in seconds to minutes.

Barnacle Buster works very well. It is moon-beams expensive though. An alternative that is highly recommended by professionals (but I haven't tried) is Rydelime.

I'm fairly sure the basic chemistry of the stuff in your waste pipes is the same as the stuff in heat exchangers. With the HE it forms quicker due to heat and evaporation. It is all marine salts (Chlorides, sulphides). The urine makes a different sort of salt which I can't remember the name of, but I would think something like barnacle buster (phosphoric acid) would have a better than even chance of nuking it.

 

Barnacle Buster, Ovlov and a few other places stock it:

Drew Marine Trac Ecological | Marine Maintenance Products (trac-online.com)

I know Auckland Engineering Services use Rydlime, it is probably widely available. The Beta Engine people use it for HE maintenance.

Rydlyme Biodegradable Descaler | Environmentally Safe

[Addem 95]

Yes I always do that especially white vinegar but  boat is new(ish) to me so I guess not everyone does that. 

[Addem 95]

1 minute ago, K4309 said:

I don't recall the chemistry of your stuff in the waste pipe, but if you are desperate for a solution you could try a heat exchanger cleaner. They get the same sea-salt encrustations of heat exchangers in seconds to minutes.

Barnacle Buster works very well. It is moon-beams expensive though. An alternative that is highly recommended by professionals (but I haven't tried) is Rydelime.

I'm fairly sure the basic chemistry of the stuff in your waste pipes is the same as the stuff in heat exchangers. With the HE it forms quicker due to heat and evaporation. It is all marine salts (Chlorides, sulphides). The urine makes a different sort of salt which I can't remember the name of, but I would think something like barnacle buster (phosphoric acid) would have a better than even chance of nuking it.

Great idea. Was thinking caustic soda (draino) but acid v alkaline is the question.  

[CarpeDiem 430]

HCl (Hydrochloric Acid). Easily obtained from any swimming pool shop about $45 for a 33% solution. Mix it with water to get a 10% concentration (NB add the acid to the water) or just go hard out and pour in @33% - stand back, wear a mask, eye protection, gloves - be well ventilated. 

HCl is the active ingredient in Rydelime. 

The active ingredient in barnacle buster is phosphoric acid.

HCl will eat up metal parts such as aluminum, galvanized steel, nickel or other active metals - don't use it on your engine.

Phosphoric Acid is more mild acting on scale and mineral deposits (so takes longer and you need more) but is fine on active metals. (excl zinc anodes - these will disappear within seconds) 

Phosphoric Acid is much harder to get hold of. I have not been able to find a consumer friendly source, so I bought barnacle buster... and yes it is moonbeams expensive. 

You could also use good old regular Coke. None of that sugar free stuff tho But it will take a lot longer. 

[Ex Machina 366]

What Carpe Diem said . I had a similar issue to you just a few weeks ago , calcified uric acid caused by reaction with salt water .

Unfortunately  it was so blocked the Hydrochloric acid couldn’t get to the standpipe in the holding tank and there was no safe way to let the acid back out . Manual removal of the pipe was the only way to clear it .

Highly recommend a downloadable book called “getting rid of boat odours” by Peggy hall . She knows her sh*t and marine heads , there’s plenty of info on maintaining pipes and systems so they don’t block …vinegar and acid based flushes feature regularly .

[Black Panther 1,589]

CD has it. But the best solution is to replace the hose.

[alibaba 77]

Not a bad idea to put a bucket of fresh water down the loo before leaving the boat anyway. Flush it  through enough so there is as little sea water in the pipes as possible. The reaction between sulphates inthe sea water [ if left in] and the bacteria in the sea water generate that horrible smell you get with the first flush when you return.

[K4309 260]

Question, what do people do on the prevention front?

I'm on a mooring so don't have direct access to fresh water to flush the whole system every time I leave the boat. I do put 4 cups of fresh water in so that the pump and seals are in fresh water and don't get calcified (which stuffs seals and makes the pump fail).

White vinegar sounds very easy, and is cheaper than water fairly much.

I do see a heat exchanger clean in my future, meaning I need to get some Rydelyme or Barnacle Buster, I wonder if a pre-emptive flush with one of those will prevent any future risk of blockages?

[K4309 260]

PS, I won a bottle of Salt Away and been wondering what to do with it. I don't actually understand what chemical it is or how it works. How would that go pouring a bit down the loo every time I leave the boat?

I've been told in no uncertain terms not to use it on the outboard for flushing. Apparently it's corrosive to aluminium and leaves a coating(?)

[CarpeDiem 430]

27 minutes ago, K4309 said:

PS, I won a bottle of Salt Away and been wondering what to do with it. I don't actually understand what chemical it is or how it works. How would that go pouring a bit down the loo every time I leave the boat?

I've been told in no uncertain terms not to use it on the outboard for flushing. Apparently it's corrosive to aluminium and leaves a coating(?)

Sulphuric Acid with some detergent mixed in.

It's water content disolves the salt. 

It's such a low concentration it won't damage your outboard.

You could flush your loo with it and leave it sitting in the pipes the sulphuric acid will help break down any minerals. 

[aardvarkash10 960]

nothing to add, but what a great thread this is!

Special mention for the lady who writes books about marine toilets and "knows her sh*t".  Appropriate.

[CarpeDiem 430]

12 hours ago, CarpeDiem said:

HCl will eat up metal parts such as aluminum, galvanized steel, nickel or other active metals - don't use it on your engine.

I will modify this to say it is damn good at cleaning up corroded/blocked exhaust mixers - but take the exhaust mixer off and drop it in a bucket at ~20% - 25% concentration.

Don't run/flush the HCl through your salt water cooling system.

[Shackleton 2]

This where I got my phosphoric acid from in Auckland.      https://www.mchem.co.nz/shop/Products/Acids/PHOSPHORIC+ACID+85%+-+5+LITRES.html#cashsales

 

[Black Panther 1,589]

Everything you have salad, pour the leftover dressing down the loo. Vinegar for calcification and oil keeps the rubbery bits lubricated.

[CarpeDiem 430]

HCl is also great for cleaning rust off tools.

This is after 3 minutes soaking.

Using baking soda to neutralize the acid. Then I spray it down with wd40 and rinse and repeat next time it's rusty...

 

[Addem 95]

I fear it is too late and too difficult. Would the HCl dissolve the concretion or just loosen it?  Then I'd have to find a way of getting it out. 

I've come up with a plan to lay a new pipe but now have to think about whether  to leave the old in situ or get it out somehow. That waste pipe is hard to work with in the confined space.

If I leave it there the pong will stay for long. If I get it out In pieces it'll spill its load all through the bilge (under said floor). 

No good options really. A case of prevention being waaaayyyyyyy better  than  cure. 

[CarpeDiem 430]

1 hour ago, Addem said:

I fear it is too late and too difficult. Would the HCl dissolve the concretion or just loosen it?  Then I'd have to find a way of getting it out. 

I've come up with a plan to lay a new pipe but now have to think about whether  to leave the old in situ or get it out somehow. That waste pipe is hard to work with in the confined space.

If I leave it there the pong will stay for long. If I get it out In pieces it'll spill its load all through the bilge (under said floor). 

No good options really. A case of prevention being waaaayyyyyyy better  than  cure. 

It will disolve it. Anything that doesn't disolve, will appear as a powdery substance in the acid.

It won't be chunky unless someone has flushed large objects down the toilet?  Eg coins or fishing sinkers... 

Where does the pipe go to?  I would expect the acid to end up there... You could then neutralize it with quantious amounts of sodium hydroxide..

You really want the acid soaking the inside of the pipe so the pipe is submerged. 

Can you get to each end?

Another option would be to connect a pump and cycle the cleaning mixture round and round then you can go with a much lower concentration. 

Just to be clear, if going with a high concentration you need to have ppe - it will fizz, spit and gas at you.  If you have any doubt handling or mixing hcl then I suggest buying Rydlyme.  The low concentration makes it safe to handle, but you'll need the recirculation method... 

 

 

[harrytom 643]

9 hours ago, K4309 said:

PS, I won a bottle of Salt Away and been wondering what to do with it. I don't actually understand what chemical it is or how it works. How would that go pouring a bit down the loo every time I leave the boat?

I've been told in no uncertain terms not to use it on the outboard for flushing. Apparently it's corrosive to aluminium and leaves a coating(?)

Thats whats it for outboard flushing,there is an attachment that fits the hose and you pour it in. I personnally just use water. I do the taste test after 5 minutes and no issues