Bilge Pumps / Shower Pumps - Advice??

[Jonny_H]

We currently have only a manual bilge pump for the low point of the boat under the engine. This keeps it quite dry, but I want to fit an electric one for piece of mind and keep the manual as an emergency backup.

Also, adjacent to the engine we have one of these:

for the aft shower. However, we the box struggles to keep up and often overflows, also the pipe is split and we end up with soapy water under the engine anyway.

Can I just drain the shower straight into the bilge under the engine and have an electric pump under there? This would also remove any water etc which runs to the low point?

Is this a sensible idea, or is it better to stick with the shower 'box' above and have a another pump for under the engine?

Also - what pump would people recommend (prob need a 2000gph ish - 2 or 3 foot lift only as the outlet I would use is the current shower one which is spliced into one of the cockpit drains at around waterline level (cockpit drain runs to the underside of the hull)).

Jonny

 

[chasroberts]

I'd be careful about pumping anything from the bilge directly overboard as contamination from oil/fuel leaks are always a possibility. Is there no way of sealing the shower compartment/sump to prevent this?

 

[Salty John]

Don't pump your shower into the bilge and then over the side. Your bilge will start to smell bad in a surprisingly short time. It's to do with bacteria, and hair is also a problem. Also, you are in danger of inadvertantly pumping bilge oil overboard.
Those sump boxes with combined pump worked well for me, I had an Attwood on my GB32 and it coped with daily showers of 'at home' pressure and volume.
Whether or not a submersible bilge pump works or not depends on the shape and depth of the bilge. I mounted mine together with the float switch on a rectangle of perspex with a 2' rod handle on one corner so I could lift the whole assembly out of our very deep bilge for cleaning and maintenance.
You can use an electric self priming diaphragm pump mounted in a dry location with a hose running down to the bilge but this is an expensive option. However, it keeps the pump and electrical connections out of the bilge and simplifies clearing debris from the pump inlet.
Whatever you do use smooth bore pipe and keep the hose as short as possible.

 

[FAITIRA]

Be careful re the height of the outlet from the electric pump, you say 2 or 3 ft, it could cause a back syphon when the pump is switched off, if the outlet (cockpit drain etc) is below the water line at any point.
The Whale "Gulper" makes a good shower pump in my experience, and also minimises the possibility of backflow.

 

[Twister_Ken]

Don't like the idea of taking it into a cockpit drain. Eventually hairy, scummy stuff might block the drain, with unpleasant consequences. If you do do it, 'rod' the drain occasionally.

My advice - shower ashore. We go to great lengths to keep water out of boats, so I don't quite get the idea of squirting it around the interior voluntarily.

 

[Jonny_H]

Ok - so if I re-pipe the shower and try to seal the pump box the shower should be sorted.

Then is there a good pump to use just for the bilge. As its under the engine there may be a bit of oil etc occassionally down there I am getting an oil absorber, but the stuff down there still won't be sparklingly clean (obviously would only pump out in this instance when well offshore) - is there a pump designed for this?

Jonny

 

[Salty John]

If it is at all possible a good idea is to build a low dam at each end of the bilge area that is directly under the engine. I did this by glassing in a plywood dam wall at each end, interconnected by a piece of 2" pipe lying on the bottom of the bilge. This meant that the oily stuff from the engine dropped into the central area where there was always an absorber pad, but water at the forward, higher, end of the bilge could flow back through the pipe to the bilge pumps. The rest of the bilge kept pretty well oil free.
I had a Rule 1000 gph electric pump and a huge capacity Edson manual pump.