Bilge pump question

[harvey38]

Our boat (38' Aquastar) apparently has two electric and one manual bilge pump. The electric ones don't work, I flick the switch, I can hear a relay making contact but no pump comes on, the manual pump has a 2" hose and takes so much effort to operate that if I did need it in anger, I would die from exhaustion before drowning!

I have just pumped about 25 gallons of fresh water out of the keel void so the bilge pumps have now moved up on my priority list!

So, my plan is to fit two new bilge pumps, both on float switches but what capacity?

 

[fredrussell]

Biggest capacity you can afford/fit in there I would say.

 

[ChromeDome]

Agree. With AUTO/Manual switch settings, so you can force start them if the automatic feature fails.

I'd go for a centrifugal pump type, tolerant to particles in the water.
And rather with external than built-in level switches.

 

[vyv_cox]

Despite the perceived advantages of electric bilge pumps there could well be a time that you will be very grateful for a manual one that can be operated for long periods. You might find this article interesting Emergency bilge pump

 

[lustyd]

Interesting to see that your outlet hose only seems to go to the cockpit Vyv. Although bulky, a longer hose which can reach the waterline would reduce effort as you wouldn't need to lift all of the water to cockpit height, just move it from inside to outside of the hull. Obviously it won't syphon out, but if you remove the requirement to lift the water it will be much easier. This would reduce energy expenditure considerably for longer use.

 

[vyv_cox]

Interesting to see that your outlet hose only seems to go to the cockpit Vyv. Although bulky, a longer hose which can reach the waterline would reduce effort as you wouldn't need to lift all of the water to cockpit height, just move it from inside to outside of the hull. Obviously it won't syphon out, but if you remove the requirement to lift the water it will be much easier. This would reduce energy expenditure considerably for longer use.

It would need to be a far longer hose than I can find space for unless I could get some flat fireman type. Might be worth thinking about.

 

[coopec]

Your boat is a 38ft so it needs 3 bilge pumps totaling 6000 gph according to David Pascoe (Marine Surveyor)
(That will be US gallons which is 5000 Imperial gallons/hour)

Boats, Yachts: All About Bilge Pumps - Those Essential Devices for Keeping Your Boat Off the Bottom

I will install Chinese pumps for freshwater, black water, shower water but will not compromise on bilge pumps. (I went for X3 24V Rule Bilge pumps which I consider the best on the market)

 

[ean_p]

Interesting to see that your outlet hose only seems to go to the cockpit Vyv. Although bulky, a longer hose which can reach the waterline would reduce effort as you wouldn't need to lift all of the water to cockpit height, just move it from inside to outside of the hull. Obviously it won't syphon out, but if you remove the requirement to lift the water it will be much easier. This would reduce energy expenditure considerably for longer use.

Do you mean connect the pump discharge hose to a skin fitting within the boat but above the waterline lusty, or extend the hose through the companionway and over the side deck and gunnels then down to the sea's surface?

 

[coopec]

Do you mean connect the pump discharge hose to a skin fitting within the boat but above the waterline lusty, or extend the hose through the companionway and over the side deck and gunnels then down to the sea's surface?

The proper way is "the pump discharge hose to a skin fitting within the boat but above the waterline"

 

[lustyd]

It would need to be a far longer hose than I can find space for unless I could get some flat fireman type. Might be worth thinking about.

A flat hose would collapse so wouldn't improve the situation unfortunately

 

[lustyd]

Do you mean connect the pump discharge hose to a skin fitting within the boat but above the waterline lusty, or extend the hose through the companionway and over the side deck and gunnels then down to the sea's surface?

Yes, for an emergency pump it's the latter. That way, once the pipe is full of water you no longer have to lift the water, just move it which greatly reduces effort. The pipe would need to be in the water to avoid the water running out. With the outlet on deck you're lifting 1kg up 5 feet for every litre of water. With the outlet in the water you're not lifting any weight at all.
Obviously a skin fitting would also work, but then you have another hole in your boat, and it would be one without anything connected most of the time so the cock would need locking closed just in case.
All a bit of a thread drift really as it doesn't help the OP it's just interesting, especially since Vyv mentioned potentially pumping for a few hours.

 

[geem]

In reality, you are never going to be pumping for a few hours on a short handed boat. We removed our fixed manual bilge pump. We still have two henderson mk5 pumps by vertue of the two lavac loos plus a stirrup pump but the heavy lifting is done by 4 electric bilge pumps giving us 19,000 litres per hour total pumping capacity. They are all Rule submersible pumps with seperate float switches. The main sump pump has a sounder on it to tell us its running and a light on the panel. The sounder can be heard from the cockpit over the sound of the wind and engine. its a reversing sounder off a truck.
One of the pumps is a 3500gph monster with 1.5 inch outlet

 

[lustyd]

Unless the electrics get wet, of course. Then you might be pumping for a while.

 

[vyv_cox]

In reality, you are never going to be pumping for a few hours on a short handed boat. We removed our fixed manual bilge pump. We still have two henderson mk5 pumps by vertue of the two lavac loos plus a stirrup pump but the heavy lifting is done by 4 electric bilge pumps giving us 19,000 litres per hour total pumping capacity. They are all Rule submersible pumps with seperate float switches. The main sump pump has a sounder on it to tell us its running and a light on the panel. The sounder can be heard from the cockpit over the sound of the wind and engine. its a reversing sounder off a truck.
One of the pumps is a 3500gph monster with 1.5 inch outlet

My article says one hour, which is a realistic time for the size of our boat.
We did not find it difficult to pump for about 15 minutes each with the discharge hose in the cockpit.

 

[geem]

My article says one hour, which is a realistic time for the size of our boat.
We did not find it difficult to pump for about 15 minutes each with the discharge hose in the cockpit.

But what do you achieve? With two onboard I much prefer to have both crew looking for a leak rather than half the crew busy pumping.
Today we sailed from Jolly harbour around to Maiden Island on Antigua. We tacked up the Boon Channel hard on the wind. The bilge alarm went off a couple of times as we tacked. This means the pump is running. It doesn't mean we have a full bilge. I went down to investigate and found the generator strainer lid was not tight. Water had been leaking in as we were heeled over. Without the pump run alarm I might not have know there was a problem. Early warning of any water in the bilge is very useful. You don't want to be looking for a leak with a flooded bilge and floating floorboards

 

[geem]

Unless the electrics get wet, of course. Then you might be pumping for a while.

That depends on boat design. Sealed battery box such that water has to get over saloon cushions helps. Early warning also helps as with all pumps running it will take some time to get over the batteries. Ability to start the generator or engine to keep pumps running is also useful.if I get to the point where I need a manual pump I will probably be abandoning ship

 

[lustyd]

Agree, although very few keep both the batteries, wiring and switches in high dry locations but it's certainly a good thing to look for if doing that kind of sailing.

 

[vyv_cox]

But what do you achieve? With two onboard I much prefer to have both crew looking for a leak rather than half the crew busy pumping.
Today we sailed from Jolly harbour around to Maiden Island on Antigua. We tacked up the Boon Channel hard on the wind. The bilge alarm went off a couple of times as we tacked. This means the pump is running. It doesn't mean we have a full bilge. I went down to investigate and found the generator strainer lid was not tight. Water had been leaking in as we were heeled over. Without the pump run alarm I might not have know there was a problem. Early warning of any water in the bilge is very useful. You don't want to be looking for a leak with a flooded bilge and floating floorboards

It still needs to be emptied when a leak has been found. In our case as written on the website the leak was from on deck but it took us hours to get it all out.

 

[geem]

It still needs to be emptied when a leak has been found. In our case as written on the website the leak was from on deck but it took us hours to get it all out.

The beauty of an electric pump

 

[NormanS]

I'm all in favour of a bilge alarm, but chary about automatic bilge pumps. I used to winter in the Caledonian Canal, and a neighbouring boat developed a leaking fuel tank, so her automatic bilge pump duly pumped about 200 gallons of diesel into the canal.