Sanitation hose replacement

[Paringa]

After 15 years the job I have dreaded is finally upon me...

My pump out toilet although reliable and whiff free has suffered a blockage, it was expected, symptoms have appeared over the last year and so it was only a matter of time before it became terminal and I needed to replace the flexible hose.

I would like to try rigid pipe but the way the hose meanders makes that impossible in certain sections so my first question is...

Would it be a good idea to just replace like for like 25mmID 33mmOD Butyl hose in one length -  approx 8M - or attempt to do rigid in two sections and join to 3 flexible sections? I am worried that the joints would prove troublesome.

I would love to use a larger bore hose or pipe but I suspect I am limited to what the original fitter did, again is there any advantage in joining fatter and thinner sections or is that asking for trouble? My head says to stick with the 25mmID Butyl in one length and keep things simple.

I intend to take the pipe route the original fitter did which is a gentle run from the bathroom to the holding tanks, my only concern at this early stage is where it goes through bulkheads but no doubt that will become clear as I start ripping out.

My plan is to temporarily move my toilet to the back cabin where the holding tanks are while I do this job so I still have a bathroom and my summer cruising goes on...

Any tips from those who have already suffered? And no prizes for the first to mention cassettes or other means of disposal, pump out is what I have and will stick with.

Thanks in advance, popcorn at the ready.

[ditchcrawler]

Biggles is your man for this but he doesn't seem to visit here now but here is his blog entry on the job http://boatbuildblog.blogspot.co.uk/2013/05/down-tubes.html

[system 4-50]

Borrow a portapott/cassetty job just for the duration of the job. Replace like for like. Return the PP.

[smileypete]

What's wrong with the hose, is it permeating?

[Richard10002]

7 minutes ago, smileypete said:

What's wrong with the hose, is it permeating?

My guess would be that it is blocked with solid limescale. On my previous seagoing boat which I bought at 11 years old, both toilet sanitation waste pipes needed replacing within a year or so, and both were blocked with rock like limescale.

Both followed tortuous routes and I'm recalling several metres of pipe in each case. The second one I replaced with more expensive Vetus pipe which seemed to be extremely good quality. I dont think multiple joints and changes between thicker and thinner pipes would have been a good idea, with respect to either smooth flowing waste, and/or the likelihood of leaks

[adrianh]

Try to fit this as 1 full length without joints. It is not good to change to larger sizes mid stream as this drastically reduces flow allowing a build up of sediment. Check   that  the hose  fitting on  the out going end has chamfered edge on the  bore to give a good  flow. I  suggest you plug both ends of the old pipe and wear disposable gloves and clothing, I used to do work at sewage works and it takes a long time to build up resistance to the bacteria present even in  old parts. Diluted jeyes fluid is good to disinfect parts and tools.

Also expect to increase hole  sizes as the  OD of tube changes depending on the  quality and manufacturer.

[WotEver]

56 minutes ago, adrianh said:

Also expect to increase hole  sizes as the  OD of tube changes depending on the  quality and manufacturer.

Great tip I picked up a while back for increasing the size of a large hole. Let's say you want to go from 1.5" to 2", there's nothing to guide the 2" cutter. So... thread the 2" cutter onto the arbor and then screw the 1.5" onto the same arbor inside the 2". The smaller cutter will protrude beyond the larger one and will act as a guide. 

[Paringa]

Thanks very much for the advice.

Pipes are blocked with a hard scale, impossible to clean so replacement the only option.

Single length it is, no joins.

Protective clothing and strong constitution being gathered.

[ditchcrawler]

15 hours ago, Richard10002 said:

My guess would be that it is blocked with solid limescale. On my previous seagoing boat which I bought at 11 years old, both toilet sanitation waste pipes needed replacing within a year or so, and both were blocked with rock like limescale.

Both followed tortuous routes and I'm recalling several metres of pipe in each case. The second one I replaced with more expensive Vetus pipe which seemed to be extremely good quality. I dont think multiple joints and changes between thicker and thinner pipes would have been a good idea, with respect to either smooth flowing waste, and/or the likelihood of leaks

Where you flushing with Sea Water,we use to have a constant problem with the urinals on the Platforms I worked on with the pipe work scaling up.

 

[Richard10002]

2 hours ago, ditchcrawler said:

Where you flushing with Sea Water,we use to have a constant problem with the urinals on the Platforms I worked on with the pipe work scaling up.

 

Yes, sea water.

[ditchcrawler]

11 minutes ago, Richard10002 said:

Yes, sea water.

WE had to often strip out the urinal pipe work as we flushed with salt water as well. 

[smileypete]

YBW forum looks like a good source of help on pump out woes. Maybe if the hose is in good nick and pricey to replace it could be crushed a little or bashed on paving or concrete to loosen the scale.

These days pubs often have low flush urinals that use enzyme blocks to prevent scale buildup, dunno if/how it'd work with seawater. Phospates like polyphosphates are another one.

Edited June 3, 2017 by smileypete

[blackrose]

On 2017-6-2 at 23:49, Richard10002 said:

The second one I replaced with more expensive Vetus pipe which seemed to be extremely good quality. 

I've had the same piece of 50mm dia Vetus sanitary hose connecting my toilet to the tank for 12 years and it's still fine. It's expensive but a good solution if the path is convoluted. All connections should be made with 2 x stainless or good quality jubilee clips rotated at 180 degrees to each other so that the screws on the clips are not in the same place on the hose.

[Paringa]

I am pleased to report the new hose went in with the minimum of fuss this weekend, I hope it won't need doing again for a few years.