Holding tank electric pump out.

[Allan]

We're going to fit a holding tank this winter on a Starlight 35. Does anyone use an electric pump to empty their tank at sea? If so, which type? Is it reliable?
Allan

 

[RupertW]

We're going to fit a holding tank this winter on a Starlight 35. Does anyone use an electric pump to empty their tank at sea? If so, which type? Is it reliable?
Allan

Are you not able to use gravity? Any pumping system will be more prone to bloackages than a simple pipe always leading downwards to the sea cock with no diverters. If you do need to pump the I'd agree electric makes sense but and a jabsco gulper would work but make sure it's accessible and can be detached with minimum leakage as you will have to clean it out from time to time depending on your crew and whether you allow paper into your loos ( we prefer the Greek system with little pedal bins and bin bags changed daily)

 

[PaulRainbow]

Are you not able to use gravity? Any pumping system will be more prone to bloackages than a simple pipe always leading downwards to the sea cock with no diverters. If you do need to pump the I'd agree electric makes sense but and a jabsco gulper would work but make sure it's accessible and can be detached with minimum leakage as you will have to clean it out from time to time depending on your crew and whether you allow paper into your loos ( we prefer the Greek system with little pedal bins and bin bags changed daily)

+ 1 to all of that, except one minor comment (borderline pedantic, i know what you meant)..... Jabsco make a diaphragm waste pump bit it isn't called a Gulper, the Gulper is made by Whale. Both are suitable.

A Jabsco/Gulper beats a macerator pump, less noise and less chance of blocking.

 

[Tranona]

Gravity tank is to be preferred, but not always possible to retrofit or get a decent size.

Suggest you go on www.tek-tanks.com where you will find a wealth of information on designing holding tanks and pumping systems. They also have a custom made tank for your boat and no doubt can advise on the layout for fitting it.

 

[BabaYaga]

Are you not able to use gravity? Any pumping system will be more prone to bloackages

This 'truth' is often repeated here, my impression however is that a large majority of posters asking for advice regarding blockages have gravity tanks...

I have had a pumped holding tank for 35 years and never experienced a blockage. Manual pump, though (Whale Gusher 8), so can not advise on electric.

 

[Allan]

Gravity is not an option. The idea of an electric pump is to get it out of way. Are they more reliable near the tank pushing or near the seacock sucking?
Allan

 

[PaulRainbow]

Gravity is not an option. The idea of an electric pump is to get it out of way. Are they more reliable near the tank pushing or near the seacock sucking?
Allan

Don't think it makes a difference with the diaphragm pumps mentioned, so i'd fit it where it's accessible for servicing.

 

[Norman_E]

Gravity is not an option. The idea of an electric pump is to get it out of way. Are they more reliable near the tank pushing or near the seacock sucking?
Allan

I use a pump to empty grey water tanks fitted in the bilges, and it is definitely better to fit the pump close to the tank outlet. I am forced to have my pump some distance from one of the tanks and it sometimes struggles to prime. The same pump serves both tanks via valves and has no problem with the closer tank.

 

[Mikedefieslife]

I would not recommend gravity. My boat came with a gravity tank and while it works exceptionally well, you end up with all 'waste' just sitting there in the pipe (2.5m in my case) and against the valve/thru-hull. I've found that while the pipe is fine, the through hull and its fittings end up stinking.

With a pump out system, waste is only ever in the pipes while pumping out, and the system can be flushed with clean water after to limit built up.

 

[galeus]

I've got one of these and had it for 15 years, but as I remember the pump even then was about £190.
It has never blocked (though seldom used for solids)
I overhauled it with duck bill valves etc. about 5 years ago but it was unnecessary as all was good.
Recently the motor has started sticking which is temporarily cured with a rap from a screwdriver, but will have to look into it.https://www.leesan.com/shop/one-sto...nd-t-series-discharge-pump-12v-or-24v-dc.aspx

 

[PaulRainbow]

I use a pump to empty grey water tanks fitted in the bilges, and it is definitely better to fit the pump close to the tank outlet. I am forced to have my pump some distance from one of the tanks and it sometimes struggles to prime. The same pump serves both tanks via valves and has no problem with the closer tank.

What pump are you using Norman ?

 

[RupertW]

I would not recommend gravity. My boat came with a gravity tank and while it works exceptionally well, you end up with all 'waste' just sitting there in the pipe (2.5m in my case) and against the valve/thru-hull. I've found that while the pipe is fine, the through hull and its fittings end up stinking.

With a pump out system, waste is only ever in the pipes while pumping out, and the system can be flushed with clean water after to limit built up.

Not been my experience with gravity although I do just have about 80cm of pipe between holding tank bottom and sea cock. The longer pipe from toilet to to the top of the holding tank does smell after 3 or 4 years though.

 

[pvb]

I've found that while the pipe is fine, the through hull and its fittings end up stinking.

What material are the through-hull etc made of?

 

[ip485]

I use a Dometic Sealand pump which I purchased from Leesan. It is a macerator pump. They also sell a wide range of other pumps. The Sealand Macerators are a great piece of kit, but at a price. With two vac. flush loos the macerator is needed and does the job dealing with a large black water tank in the bilge. Do also be careful about the wiring and fuse rating with these type of pumps. When they initially start to cycle and draw a vac the amp draw will be high.

 

[PaulR]

would that problem of waste sitting in length of gravity drain pipe below tank and causing smells be avoided if the outlet had a valve so that when holding tank was in use the pipe was largely empty (being below the valve) and pipe only full when emptying ?

 

[Tranona]

would that problem of waste sitting in length of gravity drain pipe below tank and causing smells be avoided if the outlet had a valve so that when holding tank was in use the pipe was largely empty (being below the valve) and pipe only full when emptying ?

Yes. One of my installations had a valve on the outlet from a gravity tank, but this requires a lot of space. There should be no smells coming from the hose anyway if you use proper sanitary hose.

 

[Impaler]

I’ve ordered a new Cornish Shrimper 21 and it has to be fitted with a tank according to RCD 2 so they tell me. They’re fitting an electric macerator pump together with level indication so I’d be interested to see how well it all works. I asked Cornish Crabbers if they were fitting a bypass so I could, ahem, dump directly to the oggin but apparently that’s against the rules. The no bog roll rule is OK but I thought that the quick dissolving stuff you can get from caravan shops might be the business. I don’t like a bin of bog.

 

[rogerthebodger]

We're going to fit a holding tank this winter on a Starlight 35. Does anyone use an electric pump to empty their tank at sea? If so, which type? Is it reliable?
Allan

I have one of these on my waste tank pump out

https://www.leesan.com/shop/one-sto...e-pumps/jabsco-par-macerator-pump-12v-dc.aspx

I have one of these on my shower gray water tank

https://www.leesan.com/shop/one-sto...ulper-waste-diaphragm-pump-12v-or-24v-dc.aspx

I also have one of these as an electric head discharge pump on my LAVAC and a converted jabsco head where I made a connection to where the hand pump fitted. I also added a pressure water pump as a water flush pump

https://www.leesan.com/shop/one-sto...iming-diaphragm-pump-12v-or-24v-dc-50890.aspx

 

[Windchase]

I have been using an electric pumped system for some time.
The photo shows a electrically pumped black water tank. The blue thing is the pump, and it sucks waste by varying the volume of the space under the black central circular bit. There are joker valves on the inlet and outlet sides which allow waste to pass only from right to left when the pump is in operation. When the pump sucks from the tank, it has to lift the waste only about 40cm., when the pump pushes the waste up about 100cm.

This works well, provided that the outlet joker valve has no muck in it preventing it closing properly, and the pump is not full of air. Then the pump will not prime - air is pumped back and forward through the outlet valve. Then I have to prime the pump by disconnecting the tank output pipe, twisting it round and pouring a jugfull of water in. Doesn't take long, but still ...

So, if you flush the tank after pumping out, and leave water in the pump, no problems.

p.s. I don't put toilet paper in the tank.

 

[Gunfleet]

I’ve ordered a new Cornish Shrimper 21 and it has to be fitted with a tank according to RCD 2 so they tell me. They’re fitting an electric macerator pump together with level indication so I’d be interested to see how well it all works. I asked Cornish Crabbers if they were fitting a bypass so I could, ahem, dump directly to the oggin but apparently that’s against the rules. The no bog roll rule is OK but I thought that the quick dissolving stuff you can get from caravan shops might be the business. I don’t like a bin of bog.

No loo=no tank. Have them build with no loo, add what you want later.