Electric Bilge Pumps.

[DJE]

I'm not very impressed with the current pump (Whale Supersub) It fails to generate much head and seems to struggle to open the non-return valve in cold conditions. Any recommendations for something a bit meatier? And any experience of the Johnson pumps as below?

http://www.spxflow.com/en/johnson-pump-marine/pd-marine-bilge-cartridge-and-ultima-combo/

 

[Flica]

I'm not very impressed with the current pump (Whale Supersub) It fails to generate much head and seems to struggle to open the non-return valve in cold conditions. Any recommendations for something a bit meatier? And any experience of the Johnson pumps as below?

http://www.spxflow.com/en/johnson-pump-marine/pd-marine-bilge-cartridge-and-ultima-combo/

I fear you are finding the weakness of all centrifugal pumps - a lack of pressure to overcome any head.
I use one in my shower tray, and had poor results until I decreased the head and mounted the pump higher. I doubt you'll find any significant improvement with the Johnson.
Put the non-return valve closer to the pump, that also works.

 

[Caladh]

I fear you are finding the weakness of all centrifugal pumps - a lack of pressure to overcome any head.
I use one in my shower tray, and had poor results until I decreased the head and mounted the pump higher. I doubt you'll find any significant improvement with the Johnson.
Put the non-return valve closer to the pump, that also works.

The NRV IS at the outlet exit on a Whale Supersub !!

 

[UK-WOOZY]

im about to get a new bilge pump for my jeanneau sundream 28, i was leaning towardws the Whale Supersub 1100 auto. would you advise against it.

 

[prv]

I fear you are finding the weakness of all centrifugal pumps - a lack of pressure to overcome any head.
I use one in my shower tray, and had poor results until I decreased the head and mounted the pump higher.

How do you mount a centrifugal pump higher than the water? They push water, but they won't suck it up a hose.

Pete

 

[DJE]

im about to get a new bilge pump for my jeanneau sundream 28, i was leaning towardws the Whale Supersub 1100 auto. would you advise against it.

I honestly can't recommend it. Could be that my installation is very different from yours of course. I have a fairly deep bilge sump so access to the pump is difficult and the total lift to the discharge point is about 1100mm above the sump.

 

[lw395]

How do you mount a centrifugal pump higher than the water? They push water, but they won't suck it up a hose.

Pete

I assume he meant raising the floor of the sump.

 

[DJE]

I fear you are finding the weakness of all centrifugal pumps - a lack of pressure to overcome any head.
I use one in my shower tray, and had poor results until I decreased the head and mounted the pump higher. I doubt you'll find any significant improvement with the Johnson.
Put the non-return valve closer to the pump, that also works.

I've just scrapped the centrifugal pump that was in the shower tray and I'm installing a diaphragm pump in an adjacent locker with a suction pipe from the sump. Perhaps I should do something similar for the bilge pump. Does anybody use an electric diaphragm or flexible impeller (Jabsco) pump as a bilge pump?

 

[UK-WOOZY]

this is the sump on my jeanneau and with the first whale pump i got but was too large as you can see, and the bilge outlet hole which im putting a brass skin fitting on now. so the hose is going upwards from the pump. maybe this is a better pump to get? but costs a lot more= https://www.asap-supplies.com/pumps...ilge-pumps/whale-gulper-ic-bilge-pump-si8224b

 

[skyflyer]

I've had no problems with my Rule 800 - happily pumps about 1.2m head

https://goo.gl/images/5dnUmd

 

[CCJ]

I'm not very impressed with the current pump (Whale Supersub) It fails to generate much head and seems to struggle to open the non-return valve in cold conditions. Any recommendations for something a bit meatier? And any experience of the Johnson pumps as below?

http://www.spxflow.com/en/johnson-pump-marine/pd-marine-bilge-cartridge-and-ultima-combo/

I have an earlier version, now done 18 yrs service its installed in the lazerette
https://www.mailspeedmarine.com/par-max-3.html

 

[Flica]

I've had no problems with my Rule 800 - happily pumps about 1.2m head

https://goo.gl/images/5dnUmd

My two Rules work reasonably well - but only about 1m lift. They take some time to prime and need at least 60mm of water to draw from.
The most useful bilge-emptier on my boat is the Pela 1000, that pulls up water down to 2mm.

 

[Nigelb]

+1 for the Rule, no problems after installation in my deep bilge.

 

[prv]

Does anybody use an electric diaphragm or flexible impeller (Jabsco) pump as a bilge pump?

I used a Whale electric diaphragm pump as a bilge pump on the previous boat, where we had a very deep inaccessible bilge. I was much happier lowering in a simple hose with a strum box on the end and keeping the pump dry and accessible behind a locker.

It worked perfectly well, with a Salty John electronic “float” switch (no longer sold), but the flow wasn’t particularly impressive. It was only a small pump, intended for shower trays.

Pete

 

[skyflyer]

I would never trust a diaphragm pump as a bilge pump that has to work when the boat is unattended. Strum box or no strum box it is so easy for a tiny bit or crud to get through and lodge under the diaphragm preventing a decent seal. We have diaphragm pumps for the shower sump and the fresh water supply (and you dont get much cleaner than that!) and both have failed in this way before now, despite filters and so on.
I realise impeller pumps can also get damaged or blocked by crud but IMHO its a lower risk.
(But I really would like to fit a secondary pump as a backup using a float switch triggered by a higher level!)

 

[fisherman]

I have a Johnson submersible pump, the second in 25 years. Unaffected by the detritus in the bilge and happily pumps up over the swan neck about 5 feet up and through the non return valve. It's a big one, 4000 lts I think.
Just found this which might be of use to some with less space, a 'lie down' pump:
http://www.spxflow.com/en/johnson-pump-marine/pd-marine-bilge-low-boy/

 

[prv]

I would never trust a diaphragm pump as a bilge pump that has to work when the boat is unattended. Strum box or no strum box it is so easy for a tiny bit or crud to get through and lodge under the diaphragm preventing a decent seal. We have diaphragm pumps for the shower sump and the fresh water supply (and you dont get much cleaner than that!) and both have failed in this way before now

The famously un-blockable Lavac toilet uses a diaphragm pump; I'm told the salesman used to flush his tie through it at boatshows along with sundry other detritus. Plus of course there are thousands of them out there pumping toilet waste which is a lot more than "a tiny bit of crud"! Admittedly the nature of the crud might be different (no slivers of wood or old cable-ties in toilet waste, one hopes) but pretty much every manual bilge pump is also a diaphragm pump and they don't routinely block with bilge grot.

The normal freshwater pumps use four tiny diaphragms and correspondingly tiny flap valves, I wouldn't try to pump a bilge with those but that's not what's being proposed. Shower sumps sometimes use this type as well, though I don't know why since they need to shift mildly dirty water and a lot of hair. If yours are the multi-diaphragm type then I'm not surprised they blocked, but a single large diaphragm (like a manual bilge pump with a motor working the handle via a crank) with tricuspid valves should easily cope with anything that can get through the strum box.

Pete

 

[skyflyer]

Correct - I was referring to the four small diaphragm types (but one of these was indeed the original bilge pump on my boat, factory installed). I guess the theory is that (out of the factory) only water and no crud ends up in the bilge!

But more generally there is a big difference between whether your Lavac, or shower sump stops working and whether the bilge pump packs up or runs inefficiently and flattens the battery, whilst you are sat at home!

 

[lw395]

Wooden boats that leak get the bilges washed of debris regularly.
GRP yachts tend to find an awful lot of crud in the bilge if you get serious water below. Hair, crumbs, swarf from maintenance, bits of paper, god knows.
Usually all stuck together with sump oil spillage.
The chances of most bilge pumps blocking if you develop a serious leak are huge.
Our shower drain pump is an ancient diaphragm type, which seems to cope with anything, but it does have a big 'pumpgard' ahead of it.

 

[Joker]

The shower drain pump on my boat can be used as a bilge pump by switching over a 'Y' connection. It proved useful when I had a leak in the fresh water system ending up in the bilge.