Pumping Poo

[floydraser]

Attention seeking title or what?

Denham Owl is fitted with a normal Jabsco loo and holding tank.

I've never had the pleasure of using any kind of boaty type toilet before and maybe I'm over thinking the job(by) here but: what happens when I pump the “stuff” towards the tank? I have researched the subject and found that due to the velocity attainable I have to pump 7 times to achieve 1 metre of distance but what happens when it gets to the holding tank?

I notice the inlet to the tank is at the lower end (avoiding the word “bottom”) so is there a one way valve there or is there nothing to stop the transfer pipe being part of the storage?

Does it use air to pump the “stuff” through the transfer pipe?

Ultimately, I am wondering what to find in the pipe when I disconnect it, although I could take a wild guess! I am hoping that pumping a load of clean water through followed by a good pump out will make changing the pipe a little more pleasant. 

[BroadAmbition]

Ultimately, I am wondering what to find in the pipe when I disconnect it, although I could take a wild guess! I am hoping that pumping a load of clean water through followed by a good pump out will make changing the pipe a little more pleasant. 

That's gotta be the safest bet, along with some sort of protective latex gloves of course.

Now I'm no expert in this matter (Although some forumites would loudly disagree on that one) particularly  with hand pumping Jabsco bogs.  I am however well versed in the 12v macerating types as I fitted onboard 'B.A'

I would have thought that the water drawn into the bowl then pumped along the pipe shifts any waste into the tank via water pressure.  The actual pump being higher than the holding tank would act as your non return valve too and stop waste syphoning uphill back to the hand pump.

So a good number of pumps with clean water, then a pump out prior to changing the pipe and you'll be fine.  Photo's are demanded of the operation of course in case it goes horribly wrong   

P.S  -  Did I tell you about the hilarious (True) story of when one of our girly crew blocked the macerator onboard 'B.A' ? 

I don't think MrsG or the onboard crew at the time has yet forgiven me     

Griff

[JanetAnne]

Yes, the non return valves in the pump will stop anything escaping back into the bowl but you will have some left in the pipe so be aware when you disconnect the lower end.

Don't know whether you have bought the replacement yet but we get on really well with the butyl rubber version. It's a bit more expensive but is just so easy to work with and seals perfectly.

https://www.asap-supplies.com/sanitation/sanitation-hose/seaflow-butyl-sanitation-hose-38mm

[Vaughan]

While you are at it, well worth getting a joint and valve kit for the toilet, especially the 4 sided flapper valve on the outlet at the back, which tends to get a bit "furred up" over time and then doesn't close properly. Also an opportunity to clean and grease the pump piston and shaft.

[floydraser]

10 hours ago, BroadAmbition said:

 

P.S  -  Did I tell you about the hilarious (True) story of when one of our girly crew blocked the macerator onboard 'B.A' ? 

I don't think MrsG or the onboard crew at the time has yet forgiven me     

 

No, but as we're already discussing such things, details please. 

 

10 hours ago, BroadAmbition said:

 

I would have thought that the water drawn into the bowl then pumped along the pipe shifts any waste into the tank via water pressure.  The actual pump being higher than the holding tank would act as your non return valve too and stop waste syphoning uphill back to the hand pump.

 

Yes but as the lever is switched over it closes off the water inlet to the bowl. I wonder if it then pumps air behind the "stuff" or if it draws in water, bypassing the bowl? 

[Vaughan]

15 minutes ago, floydraser said:

Yes but as the lever is switched over it closes off the water inlet to the bowl. I wonder if it then pumps air behind the "stuff" or if it draws in water, bypassing the bowl? 

It just pumps out the bowl, with no rinsing water. This is where a new flapper valve at the back will give you stronger pumping.

[OldBerkshireBoy]

As one who has to work with the house type of macerators from time to time I suggest a smear of Vic in the nostrils helps those not used to such things.

[floydraser]

24 minutes ago, OldBerkshireBoy said:

As one who has to work with the house type of macerators from time to time I suggest a smear of Vic in the nostrils helps those not used to such things.

And as mentioned in one of my recent videos I have a 3M face mask from Screwfix which also keeps out smells. I'll be doing both when the time comes. And yes, it should all be on video in glorious colour!

[MauriceMynah]

It might be that I don't recognise the orientation of that picture, but all three pipes showing, appear to be entering the top of the tank. I can think of no good reason why one would have the "input" fitting to the tank in any other position than the top. Please confirm!

PS, I shall look forwards to the film!

PPS, Don't listen to Griff, he don't know s**t

[vanessan]

43 minutes ago, OldBerkshireBoy said:

As one who has to work with the house type of macerators from time to time I suggest a smear of Vic in the nostrils helps those not used to such things.

Good old Vic - as used sometimes by those in attendance of autopsies too and I can understand why!

[OldBerkshireBoy]

If that dark coloured circlular fitting is a high level warning float/ sender I would be tempted to remove and clean it and check it is working whilst out of the tank.

[Oddfellow]

make sure you replace any pipework with proper sanitation hose like the white ones in your shot. 

 

[Mouldy]

We recently had the poo pipes changed on Norfolk Lady.  I understand from talking to Paul at the yard, that bagging the ends of the old pipes is advisable to save the potential for muck spreading as you pull them through the bilges.

Good luck!!!

[MauriceMynah]

26 minutes ago, FreedomBoatingHols said:

make sure you replace any pipework with proper sanitation hose like the white ones in your shot.

Interesting Andy. It's a job I last did in the 90s. The pipe I used looked much more like the black pipe in the picture, except that it was green. What is the difference between the two?

[grendel]

colour

[grendel]

just ask anyone who was on the workparty when Royal Tudor had her dump-through poo tank removed, it had to be cut in half with a grinder.

Timbo will tell you as his descriptive powers are far better than mine. 

[Oddfellow]

38 minutes ago, MauriceMynah said:

Interesting Andy. It's a job I last did in the 90s. The pipe I used looked much more like the black pipe in the picture, except that it was green. What is the difference between the two?

Sanitation hose is made with materials that are designed to not leach the unpleasant odours of what they carry. They tend also to remain flexible for longer than the green suction delivery hose that's shown in the picture. 

[Regulo]

Also, the inside of the white hose is smooth, to stop accumulation of the . . . bits! 

[stumpy]

14 hours ago, BroadAmbition said:

 

P.S  -  Did I tell you about the hilarious (True) story of when one of our girly crew blocked the macerator onboard 'B.A' ? 

I don't think MrsG or the onboard crew at the time has yet forgiven me     

Griff

If it involved a Mars bar (other chocolate confectionery is available) - been there,done that. The old ones are the best!

[floydraser]

4 hours ago, MauriceMynah said:

It might be that I don't recognise the orientation of that picture, but all three pipes showing, appear to be entering the top of the tank. I can think of no good reason why one would have the "input" fitting to the tank in any other position than the top. Please confirm!

PS, I shall look forwards to the film!

PPS, Don't listen to Griff, he don't know s**t

The brown pipe to the left is the breather, small white is the "rinse" and goes to a deck fitting next to the pump out fitting, which is where the other white pipe goes to. The white ones are the ones replaced by me and are the kit for the job by Lee Sanitation. 

The inlet is at this end of the tank (bottom of the pic) and goes in a couple of inches from the bottom of the tank. I've already cut a chunk out of the fridge support to allow access to the clamp.

In further

preparation I have made bungs for the ends of the pipes and the tank as I envisage it taking a while to get the old pipe out and thread the new one in through the holes in the bulkheads. I will also put some old towels etc in the bilge to catch anything before it gets to the bilge pump, and have plenty of wheelie bin liners to take the old pipe away.

4 hours ago, OldBerkshireBoy said:

If that dark coloured circlular fitting is a high level warning float/ sender I would be tempted to remove and clean it and check it is working whilst out of the tank.

I thought that's what it must be but there is no gauge or warning light anywhere and I have never traced the wires to see where they go. And it's not shown on the wiring diagram. Last time I disturbed a cover like that on a water tank some of the bolts snapped so I think I'll try and see if it works first.  

I've just realised that I covered this in DO12 so here's a link. The tank bit is right at the beginning so no need to watch it all the way through.

 

[Regulo]

That seems wrong to me. The sucky-outer should be at the bottom of your tank, surely? Unless there's a drop-pipe inside the tank.

[floydraser]

2 minutes ago, Regulo said:

That seems wrong to me. The sucky-outer should be at the bottom of your tank, surely? Unless there's a drop-pipe inside the tank.

I'm sure there must be a drop pipe and I'm wondering if there would be a pipe from the inlet going upwards. I have some photos somewhere of the stampings on the top of the tank and I'll try and trace the manufacturers.

 

[ZimbiIV]

On Zimbi the toilet is connected to the top of the tank, the pump out to the bottom and the rinse out to the opposite wnd of the tank to the pump out. 

Rather than faff around changing valves etc have a look for the complete pump assembly, I got one for £15 more than the cost of a service kit, changed the whole assembly in 15 mins and no mess to clean up!

paul

[floydraser]

21 minutes ago, ZimbiIV said:

On Zimbi the toilet is connected to the top of the tank, the pump out to the bottom and the rinse out to the opposite wnd of the tank to the pump out. 

Rather than faff around changing valves etc have a look for the complete pump assembly, I got one for £15 more than the cost of a service kit, changed the whole assembly in 15 mins and no mess to clean up!

paul

Yes, I've had a quick look and found the whole pump is worth the extra.

I've also had a look at tank designs and every one shows the inlet at the top. So mine must have the inlet extended upwards, possibly with a "U" on top. This must be the case to prevent back pressure. The connections have been that way for years so can't be wrong. I could confirm this by risking taking the level indicator access off as OBB suggests, and shoving my action camera down. 

[MauriceMynah]

Remind me never to ask Floyd if I can borrow his camera.