Manual Bilge Pump Location?

[toddster8]

I've recently acquired a second manual bilge pump and*thinking about where to install it. *I've already had to move the old one once and don't want to cut any more unnecessary holes in the boat. *

Somewhere I read that there should be one pump that can be operated from the helm and another that can be operated from the nav station. *Sounds reasonable at first thought. *The old one is located at the back of the boat, out of reach from the helm. So I guess its operation wouldn't interfere with the helmsman. *But the helmsman is likely going to be either me (also the pump-lackey) or Otto. *Any other theories on this?

A different idea was to keep the "spare" screwed to a board with hoses coiled up, so that it could be deployed wherever needed. *But that turns out to be a fairly bulky object for my boat. *

[Lepke]

In a single bilge pump boat, the pump is usually placed at the lowest place in the hull. If you want to control the pump from two places it just takes a little wiring. Most pumps normally operate with a detector of some type that turns on the pump. The switch is usually wired with a lite that shows when the pump is running. You can add a noise maker of some kind and a remote indicator lite.

[toddster8]

The topic is manual pumps, not electric sump pumps. The manual pump is located where the operator is and the pickup is a hose going into the bilge. Or wherever. The manual pump is likely to be operated in an emergency, or if the electric pump or battery has failed.

Presumably the logic of the helm/nav station dual pump recommendation is that those are two places where you might need to be if the boat is in trouble. So you can pump and steer or pump and navigate/talk on the radio at the same time. I don't know what the logic for putting the old pump far aft was.

I suppose in a non-emergency, you'd still sometimes like to be able to pump the bilge, when the electric pump has failed, from some place that you can actually see the bilge.

[CarlF]

If it's just you and Otto, have you ever tried to hand pump for more than 15 minutes? It's really hard to keep up more than 10 gallons a minute for any length of time.

Also (or instead) install a big electric bilge pump (like the rule 3700) above the normal bilge water level. Attach a 1 1/2" flexible hose (home sump pump discharge hose is cheap) and leave it coiled in the bilge. No float switch. You're only going to turn this on in an emergency. Make the hose long enough to reach to an opening port or the cockpit coaming with a bit of rope to hold it there. If possible, run the engine while using the pump to give it 13+ volts for more power.

Also, carry a few tubs of StayAfloat. What doesn't come in doesn't have to be pumped out.

https://www.youtube.com/watch?v=888wQhRcmjQ

[Pizzazz]

Installing too many emergency only pumps in a small boat can get messy for little potential benefit. My emergency approach will be to use the manual waste disposal pump (empty the waste tank, disconnect the tank hose, open the valve). It takes a couple of minutes, could be a little stinky but for emergency use it will suffice.

[TrentePieds]

Quote: "The manual pump is likely to be operated in an emergency..."

And the best of British luck to you :-)! Bilge pumps are housekeeping devices, rather like vacuum cleaners ashore. They are for tidying up the bilge when your housekeeping/maintenance has been less than adequate.

There is no bilge pump that I know of that you can carry in even a large sailboat, and certainly not one that you can operate by hand main force, that will keep you from sinking if you've punched more than a minor hole in 'er or gotten seriously pooped.

It's a truth universally acknowledged there is no more effective bilge pump than a scared man with a bucket, so I think you are worrying for naught.

There is more percentage in worrying about how not to get holed or pooped :-)

TP

[HopCar]

I agree with a lot of what Carlf said, except I want the big electric pump to come on if I'm not on the boat. Mine, a Rule 3700, has a float switch and an Auto /Manual selector switch. It is plumbed to an above the waterline thru-hull and ready to pump at any time.

I also can pump my bilge with my engine cooling pump in an emergency.

I'm not a big believer in manual pumps. If you are pushing tha handle on the pump, you're not stopping the leak.

[SV Bacchus]

Originally Posted by HopCar

I'm not a big believer in manual pumps. If you are pushing tha handle on the pump, you're not stopping the leak.

Kinda like that old joke about running from the cops, you're still going to jail but you're going tired.

Same thing here, probably going swimming, very tired, when your boat slips out from under you. Better to be fixing the leak!

[knockabout]

if your back up manual pump is near the helm it is easy to give it a couple of pumps to check the bilge is dry for peace of mind

[daletournier]

Originally Posted by TrentePieds

Quote: "The manual pump is likely to be operated in an emergency..."

And the best of British luck to you :-)! Bilge pumps are housekeeping devices, rather like vacuum cleaners ashore. They are for tidying up the bilge when your housekeeping/maintenance has been less than adequate.

There is no bilge pump that I know of that you can carry in even a large sailboat, and certainly not one that you can operate by hand main force, that will keep you from sinking if you've punched more than a minor hole in 'er or gotten seriously pooped.

It's a truth universally acknowledged there is no more effective bilge pump than a scared man with a bucket, so I think you are worrying for naught.

There is more percentage in worrying about how not to get holed or pooped :-)

TP

The scared man with a bucket anology dosent work for me. I have a smaller 1850g bilge pump but recently added a extra 3700g which utilizes the manual pump hose on. The idea is i will never manually pump anything close to 3700g/hr but if my electrics were to fail i can turn a valve and disconnect the hose from the 3700 and hand pump, i should be able to convert to manual pump if need be in less than a minute if needed. All up my pumps will pump 5550g/hr. I agree that any sort of substantial hole would be difficult to handle with anything but a very large crash pump.

[TrentePieds]

That's interesting, Dale.

If I read you aright, you are set up to shift a weight of water equal to about 1.5 times your boat's displacement in cruising trim in an hour? Something like 47K lbs/hr? That, I'll admit, would take a man both strong and swift and tireless as well as a skookum bucket.

I should prolly do the math and see how a system like that would fit in TP. Let's say a 3 foot head from strumbox to through-hull [she's only little :-)]. 2" hose - no, let's make it 3". What's the pressure we'd need to shift it all in an hour? What's the HP we'd need to generate that many PSI? What'd be the amps at 12V required to generate those HP?

I really have no immediate feel for how those numbers would fall out. But it's interesting to think about.

Did you work those those numbers for your boat?

For some perspective on the bucket gag: It'd be reasonable to pick up, say, 2.5G at a time, i.e 20lbs in round numbers. That's about as much as a well-grown lad can scoop up outta the bilge, get up the ladder, through the companionway and over the side without a struggle. So to do your 47K lbs would take 47,000/20 = 2,360 trips in the hour, i.e. 3,600/2,360 trips per second, or one trip every second and a half. Yikes :-)!

Me - I'd rather drown ;-)!

TP

[Copacabana]

Originally Posted by toddster8

I've recently acquired a second manual bilge pump and*thinking about where to install it. *I've already had to move the old one once and don't want to cut any more unnecessary holes in the boat. *

Somewhere I read that there should be one pump that can be operated from the helm and another that can be operated from the nav station. *Sounds reasonable at first thought. *The old one is located at the back of the boat, out of reach from the helm. So I guess its operation wouldn't interfere with the helmsman. *But the helmsman is likely going to be either me (also the pump-lackey) or Otto. *Any other theories on this?

A different idea was to keep the "spare" screwed to a board with hoses coiled up, so that it could be deployed wherever needed. *But that turns out to be a fairly bulky object for my boat. *

Toddster, I think that you've got it pretty much spot on- 2 manual bilge pumps: one at the helm and another near the nav table. This way you can pump as you steer or radio for help. I have a third one in the head, for pumping the shower sump, which I'm going to re-purpose as a general emergency pump. I'd like to add a length of hose to it that can reach different parts of the boat. I'll keep it coiled up and ready, but in an emergency it could be used to pump out any compartment in the boat. Anyhow, such is the theory...

[HopCar]

Originally Posted by TrentePieds

That's interesting, Dale.

If I read you aright, you are set up to shift a weight of water equal to about 1.5 times your boat's displacement in cruising trim in an hour? Something like 47K lbs/hr? That, I'll admit, would take a man both strong and swift and tireless as well as a skookum bucket.

I should prolly do the math and see how a system like that would fit in TP. Let's say a 3 foot head from strumbox to through-hull [she's only little :-)]. 2" hose - no, let's make it 3". What's the pressure we'd need to shift it all in an hour? What's the HP we'd need to generate that many PSI? What'd be the amps at 12V required to generate those HP?

I really have no immediate feel for how those numbers would fall out. But it's interesting to think about.

Did you work those those numbers for your boat?

For some perspective on the bucket gag: It'd be reasonable to pick up, say, 2.5G at a time, i.e 20lbs in round numbers. That's about as much as a well-grown lad can scoop up outta the bilge, get up the ladder, through the companionway and over the side without a struggle. So to do your 47K lbs would take 47,000/20 = 2,360 trips in the hour, i.e. 3,600/2,360 trips per second, or one trip every second and a half. Yikes :-)!

Me - I'd rather drown ;-)!

TP

That's interesting, I never thought to calculate the weight of the water that the pump will move. It's not 47k but still an impressive number.

The Rule 3700 will push 2900 gallons per hour up a 1 meter head through a 1-1/2" hose when powered with 13.6 volts.

If you use 8.5 pounds per gallon for the seawater, that's 24,650 pounds per hour.

[TrentePieds]

Not quibbling, Hopcar — just elucidating :-)

At a 3 foot head there is a reduction in flow to 2,900 GPH if the pump is feeding off an alternator and getting the full shot of 13.6V. So sez Rule Pumps. If the pump is sucking juice straight off a battery at 12.5V there is a further reduction in flow to, say, 2,600GPH. That's 70% of the rated (promised) output. The draw is 15 Amps, so sez Rule Pumps, so I would expect that after a coupla hours the battery voltage (in real life) would be down to about 12V and there would be a commensurate further reduction in flow. I don't see the entire curve anywhere, so your guess as to what the actual flow would be is as good a mine.

15 amps at 12V is, as you know, 180 Watts. One solitary horsepower is, as you also know, 750W, and therefore 180 W = (180/750)HP = .25HP. What is less well known, tho I expect you know it, is that your average geezer-type sailor can only sustain an effort of something like .10HP over a longish period of time, but certainly not a quarter of a horse. If a terror stricken geezer on the end of a manual pump can sustain 1/10 HP, then I would expect that he could pump 2,600(.1/.25) = 2,600(10/25) gallons per hour, call it 1,040 GPH. That would be 1,040 *8.5 lbs = 8.840 lbs/hr or, say, 4 tons/hr.

But in real life that don't compute because a manually operated piston pump is not nearly as efficient as a centrifugal pump. The upshot is that a manual pump can only be a tidying-up device, NOT a device that will save your butt in a real emergency. To think that it can be is, methinks, delusionary :-)!

Some further perspective: Long time ago - in the prime of my life - I attempted to keep a 100W common or garden variety incandescent light bulb lit to full intensity by pedaling like fury on a stationary bike that drove a 120V alternator. I could get it to full intensity in spurts, but couldn't hold it there continuously. And after ten minutes I was totally knackered. And that was using the strongest muscles in the body.

So I'm back to where we started - a gentle caution to the OP that perhaps installing a hand pump as an emergency pump needs re-thinking :-)

Mais chacun à son goût :-)!

TP

[roland stockham]

I like to have a manual pump below deck out of the weather, ideally placed so that you can get up, pump and be back in the bunk with min disturbance. If you have a leak that need pumping for 15min every hour it allows you to do it and get some kip. Would also look at what the clearest part of the bilge is to minimize clogging.
When people think about pumps they often think of sinking. Much more likely is something like a deck fitting pulling out and letting in water every wave. Easily tackled with a hand pump. Electric pumps are good but they burn out and flatten batteries. Hand one work for as long as you can!