how do holding tank pump outs work?

Burnham Bob

Burnham Bob

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having only ever emptied the tank by using the macerator pump at sea, i was wondering how they do it at marina pump outs. do they simply stick a long tube down the deck access hole until they reach the tank?

any restrictions on the length of the pump out tube? havng read another post on difficulty with some bilge tanks i was wondering about mine which is actually under one of the bunks in the foc'sle.
 
Burnham Bob said:
having only ever emptied the tank by using the macerator pump at sea, i was wondering how they do it at marina pump outs. do they simply stick a long tube down the deck access hole until they reach the tank?

any restrictions on the length of the pump out tube? havng read another post on difficulty with some bilge tanks i was wondering about mine which is actually under one of the bunks in the foc'sle.
Click to expand...

go to the Blakes Lavac schematic details there
 
been there sailorman and they are helpful on pumping out using the Lavac pump buy no mention I can find of what marina pump out stations do - although i imagine its fairly simple and much as i described. i'm just curious as we're off soon to the continent and will be usin pump outs
 
Burnham Bob said:
been there sailorman and they are helpful on pumping out using the Lavac pump buy no mention I can find of what marina pump out stations do - although i imagine its fairly simple and much as i described. i'm just curious as we're off soon to the continent and will be usin pump outs
Click to expand...

not many pump-outs ready,according to recent post from Dutch Forumites
 
Burnham Bob said:
been there sailorman and they are helpful on pumping out using the Lavac pump buy no mention I can find of what marina pump out stations do - although i imagine its fairly simple and much as i described. i'm just curious as we're off soon to the continent and will be usin pump outs
Click to expand...

Do you have the standard pumpout fitting with a dip tube into your tank? The pumpout stations work by vacuum, so you need to have a large capacity breather as well. As Sailoman says, despite all the hype there are very few pumpout stations so you will almost certainly have to use your own pump at sea. Check with the marinas you plan visiting to find out if they have facilities.

Know it is not "le continent", but in Poole with 8000 resident boats and hundreds of visitors there is only one pumpout facility!
 
Tranona said:
Do you have the standard pumpout fitting with a dip tube into your tank? The pumpout stations work by vacuum, so you need to have a large capacity breather as well. As Sailoman says, despite all the hype there are very few pumpout stations so you will almost certainly have to use your own pump at sea. Check with the marinas you plan visiting to find out if they have facilities.

Know it is not "le continent", but in Poole with 8000 resident boats and hundreds of visitors there is only one pumpout facility!
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Holy Shit :rolleyes:
 
Yep! Good thing we have strong tides here - also you should see the size of the mullet frollicking around my boat this afternoon.
 
Pump out facility

Our club fitted a pump out facility about 2 years ago. I have never seen it used however it was fitted to show lip service to the environmental rules. (at great cost)
I have often wondered how it works. A sign says no one is to use it unless they have been trained.
I would find it difficult to imagine it could work on suction unless the ships tank has a pump out connection which in itself is a long tube to the bottom of the tank. The shore based gear only seems to have a hose connection. olewill still wondering how it works.
 
We had a pump out this afternoon. The pumpout boat arrived with a long hose and a soft sink plunger type end fitting which the guy fitted on the waste fitting on deck and it simply sucked it out. I was told it sucked roughly one gallon per second, so 20 seconds of suck is 20 gallons of goop. In our USA marina, overboard pumpouts are forbidden unless you are more than 3 miles out to sea and the overboard valves must be locked closed or you face big fines and yes they do enforce it. No problem as a weekly pumpout in the berth is free and if you need more just go on the fuel berth for it.
 
Pump outs

William_H said:
Our club fitted a pump out facility about 2 years ago. I have never seen it used however it was fitted to show lip service to the environmental rules. (at great cost)
I have often wondered how it works. A sign says no one is to use it unless they have been trained.
I would find it difficult to imagine it could work on suction unless the ships tank has a pump out connection which in itself is a long tube to the bottom of the tank. The shore based gear only seems to have a hose connection. olewill still wondering how it works.
Click to expand...

The local council installed one on the dock at Huskisson in Jervis Bay but I've never seen it used. It's kept locked and there is a phone number if you want to use it. There are half a dozen or so whale/dolphin watching boats which have toilets on board, so would have thought I would have seen one use it by now.
Most of Jervis Bay is a Marine Park but I was told by the licensing authority that there is no requirement to have a holding tank, which I find surprising.
Sailorbaz
Our boat has a Porta Potti so nothing goes overboard
 
Your holding tank pump out system includes a standpipe inside the tank itself. The pump out fitting simply fits into the deck fitting (sealed with a captive 'o'ring on the pump out hose..) and suuuuuuuucks... There is no need for the dip tube because of the standpipe inside your black water tank. Easy! (if smelly!)
 
rosssavage said:
Your holding tank pump out system includes a standpipe inside the tank itself. The pump out fitting simply fits into the deck fitting (sealed with a captive 'o'ring on the pump out hose..) and suuuuuuuucks... There is no need for the dip tube because of the standpipe inside your black water tank. Easy! (if smelly!)
Click to expand...

Yeah, it's a great system especially if you look at most of the deck fittings have a small chain between the fitting and the actual plug to prevent it from going overboard.
Really helps to buildup the vacuum .... not!

Cheers
 
aluijten said:
Yeah, it's a great system especially if you look at most of the deck fittings have a small chain between the fitting and the actual plug to prevent it from going overboard.
Really helps to buildup the vacuum .... not!

Cheers
Click to expand...

Absolutely, I had to cut ours off so I could screw the pumpout to the deck fitting. Thereafter, in Holland where pump out facilities are plentiful, it works very well.
 
Pump-outs are widely used on the Thames and Medway. The proper pump-out socket does not have a chain for reasons already mentioned. The pump-out probe consists of a plain tube that fits into a plain section of the socket and has a o-ring for a seal. There is also an on/off valve in the probe. The pump out installion consists of an electric vacuum pump which is run for about a minute with the valve closed to build up negative pressure. Then, when the valve is opened the tank contents are sucked out pretty fast. As has been mentioned earlier, the deck socket connects to a stand pipe built into the holding tank. When the tank is empty one usually closes the valve and uses a hose to run some clean water into the tank for a rinse before pumping out again. Some boats have a rinse pipe plumbed into the tank as well.
 
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