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Old 30-10-2012, 06:18   #1
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Crash Pumps?

The horrifying loss of the Bounty due to loss of pumps has made me think again about bilge pumps.

One of the first things I did to my boat when I bought her three years ago was to install two additional bilge pumps, together with attendant piping and through-hulls -- it was a lot of trouble. One of them is a nominally 3500 gallons per hour high capacity Rule job, which I think of as my crash pump.

But nominally 3500 gallons per hour is in reality quite a bit less than that. Besides that -- here's the really chilling thing -- normal type bilge pumps get clogged up when trying to pump much water. I convinced myself of that when I ran a hose into my engine bilge last summer. Now my engine bilge (it's a separate bilge from the main bilge, for environmental reasons, I guess) is pretty clean, or at least looked pretty clean, but the Whale Supersub I installed in there (with separate pipe and through-hull out the transom -- a hell of a job to install) quickly clogged up and stopped pumping. I was amazed that a tiny bit of junk stopped it from doing its job. I kept clearing it over and over again, and like that, working it constantly, it barely kept up with a hosepipe.

So much for dealing with a real leak.

My main bilge is very deep, so I wonder how realistic it would be to keep the big crash pump clear in case of a real emergency. Hmmmm.

And anyway, the capacity of it is not going to be enough to deal with a major leak.

So I start to think again about whether it makes sense to have a dedicated crash pump, a real heavy duty dewatering pump on board, just in case. I though about, and then rejected the idea of a gasoline (petrol) powered trash pump -- can't be stored inside the boat, and have to start it often and probably often clean the carb to keep it from gumming up, then it won't start when you need it most. And where to keep it? Nowhere.

So now my thinking is to buy an electrically powered trash pump, like this one: Honda Pumps: WSP100 Submersible Water Pump

What I particularly liked was the phrase handles solids up to 2"

Where to keep it? Simples -- in the bilge.

How to pipe it? No need to plump it in permanently, methinks -- you can buy 2" and 3" flat hose like firehose, sold in 50' lengths, which rolls up compactly. You would only need this in a real emergency, and then you just connect the hose, and run it out a hatch over the side.

Yes, its functioning will be dependent on having AC power on board.

BUT -- I have two good sources of AC power -- my inverter, and my diesel genset. Either one of these will handle the 1.2kW load with ease. I suppose the chances of neither working is going to be less than the chances of a problem with a rarely used gasoline engine. Downside, I guess, is whether high water might take out my AC system. I reckon it might just do that if the water got up over my inverter (through which all AC power goes), which is in my engine room, mounted somewhere near the waterline. Hmmm.

If I had a portable genset which could run it, then I would have triple redundancy, but I'm afraid my little Honda will never run that pump Hmmm.

What do you guys think? Any of you keep dedicated crash pumps/ dewatering pumps on board?

Another plus of having something like this on board is that you might save a fellow sailor sometime.
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Old 30-10-2012, 06:26   #2
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Re: Crash Pumps?

as long as you have power you can have pumps...bounty lost generator--but sh e has twin screws--if sh was motoring, there shoul dhave been pump capability--why no dc backup
or did those die first??
or is it more practical to only have and use ac current powered pumps on those ships?
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Old 30-10-2012, 06:32   #3
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Re: Crash Pumps?

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Originally Posted by zeehag View Post
as long as you have power you can have pumps...bounty lost generator--but sh e has twin screws--if sh was motoring, there shoul dhave been pump capability--why no dc backup
or did those die first??
or is it more practical to only have and use ac current powered pumps on those ships?
I know that larger commercial vessels have lots of systems which run only on AC power, and so they are dependent on having a generator running at all times. But I think there must be multiple redundant sources of power for critical systems. So I don't know how Bounty lost her pumps. I guess that story will come out.

I am guessing that there might be a design mistake in there somewhere. A wooden ship is much more dependant on pumps than steel or plastic -- we all know what they do in heavy weather. In the olden days they had big hand operated pumps with a bunch of burly sailors operating them. Nowadays I guess you would really, really want to have some redundancy, probably a lot of redundancy, considering the fact that you really can't afford to lose pumps in heavy weather as Bounty seems to have done.
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Old 30-10-2012, 06:36   #4
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Re: Crash Pumps?

Continuing the line of thought -- I already have three redundant sources of AC power on board, although I have no critical systems running on AC power (unlike a large commercial vessel). If I were to install a switch and separate outlet on my diesel genset, to isolate it from the boat's main AC power system, then it could be switched to be entirely independant from other systems. The genset is installed in my engine room above the main engine and so well above the water line. I would feel pretty good about that as an emergency power source, as long as I could disconnect it from the main AC power system, parts of which could get flooded.
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Old 30-10-2012, 06:37   #5
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Re: Crash Pumps?

i still need a big huge emergency dewatering device--but i am dependent on my dc pumps which arent quite burly enough to save a boat during this kind of catastrophic failure. we pray a lot. and we try like crazy not to get caught in bad weather ...so far...
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Old 30-10-2012, 06:45   #6
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Re: Crash Pumps?

Specs on the page you linked says 47 amps starting current, 11.1 amps running.

That's a centrifugal pump, usually their capacity drops rapidly against back pressure. The flat fire hose is going to have back pressure. My friend thought this would be a good idea with a Rule 8000. It didn't work well.


I attempted to explore disaster pumps awhile ago, haven't figured it out yet
http://www.cruisersforum.com/forums/...read-6547.html


The Ericson pump is gone, but these people now make it.
Fast Flow Emergency Bilge Pump

One thing I thought later about the pump on the prop shaft is you're going to be motoring at some major fraction of your hull speed to make it work. Hard to work on stopping the leak and possibly forcing water more quickly into the boat.
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Old 30-10-2012, 06:55   #7
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Re: Crash Pumps?

I can't see having a crash pump on a cruising boat relying on AC. You won't be using the pump unless you have a big water problem on the inside of the boat. The two small Honda gas pumps are light, take little space and are priced right. The WX10 weighs 14 lbs.
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Old 30-10-2012, 07:14   #8
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Re: Crash Pumps?

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Originally Posted by Dockhead View Post

I am guessing that there might be a design mistake in there somewhere.
Perhaps, but it seems to me the problem was compounded by the captain. Here is a quote from the AP:

"When the Bounty set sail last week, the captain running the ship made famous in Hollywood adventure films believed he could navigate around Hurricane Sandy and weather the storm."

A tragic, tragic and very human error in judgement. I pray for his eventual rescue--there is still a chance as the gulf stream waters are near 80-degrees.
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Old 30-10-2012, 07:15   #9
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Re: Crash Pumps?

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Originally Posted by Paul L View Post
I can't see having a crash pump on a cruising boat relying on AC. You won't be using the pump unless you have a big water problem on the inside of the boat. The two small Honda gas pumps are light, take little space and are priced right. The WX10 weighs 14 lbs.
Well, you can't keep the gasoline pump inside the boat where the gasoline fumes can get into the bilge. So where do you keep it? In the anchor locker?

Besides that, a rarely used gasoline engine is susceptible to having a gummed-up carburetor. I guess you could start it up, run it, then drain the carb, etc., etc. -- seems like a lot of trouble. What if you don't happen to have a full gas can on board to fuel it? etc., etc. Really doesn't seem like a good solution to me.

I would rather rely on my diesel genset, which is mounted above the water line, and which is backed up by main engine driving the inverter, and could even be run off my battery bank.

Another question is the hose -- will such a pump produce an adequate flow against a firehose-type flat hose? The head will not be all that great -- less than 2 meters, I think. But I've never used that type of hose so I don't know what kind of force is needed to overcome the flatness. All I know is that they sell this type of hose together with these pumps.

One more point: The WX10 Honda pump only pumps 37 gallons per minute -- less than my Rule bilge pump. A nearer equivalent to the electric pump I found is the WB20, which is, indeed, inexpensive, but weighs 47 pounds and looks to be quite bulky.
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Old 30-10-2012, 07:20   #10
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Re: Crash Pumps?

and, that, my dears, is why i still do not have a megapumperfromhell to dewater my precious formosa--
where to stash the beast
where to use the beast, altho it would have to be ondeck as boat is slipping into wetville...and the hoses--
omg--almost for got--how to power the beast....
oops--forgot--how the heck do i lift the damn thing from its nice safe deeeep hidey hole onto the trying to be wetter than i really want deck.....alone....this could well sukk, if given the chance....
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Old 30-10-2012, 07:25   #11
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Re: Crash Pumps?

De-watering is a separate issue from the actual source of the water. Many people think about pumps, but few think about how to stop the water intrusion. Even a small hole of 2" will overwhelm most recreational bildge pumps.

In the commerical and military worlds of Marine Transportation, de-watering is considered a way to increase time to effect a repair or slow the water intrusion in order to keep the ship functioning.

Of the boats I have encountered, very few have the tools necessary to rip cabinets away to expose a hole or broken thru hull. Also very few have precut pieces of plywood, drilled for bolts to replace a broken port hole or hatch. Or more importantly, many have no plan or the means to try and patch that hole.

Just something for thought....
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Old 30-10-2012, 07:38   #12
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Re: Crash Pumps?

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Originally Posted by jeremiason View Post
De-watering is a separate issue from the actual source of the water. Many people think about pumps, but few think about how to stop the water intrusion. Even a small hole of 2" will overwhelm most recreational bildge pumps.

In the commerical and military worlds of Marine Transportation, de-watering is considered a way to increase time to effect a repair or slow the water intrusion in order to keep the ship functioning.

Of the boats I have encountered, very few have the tools necessary to rip cabinets away to expose a hole or broken thru hull. Also very few have precut pieces of plywood, drilled for bolts to replace a broken port hole or hatch. Or more importantly, many have no plan or the means to try and patch that hole.

Just something for thought....
I reckon in my case -- YMMV -- a disastrous leak is going to come from a limited set of possible scenarios: either the stern gland fails, the prop shaft falls out, or a through-hull or hose fails.

I have a watertight crash bulkhead forward and my whole hull forward of the keel is Kevlar. Maybe a floating container would hole us, or maybe not. But if something really crushes the hull, then forget crash pumps anyway -- just take to the liferaft (that's why we have it!).

So the scenario we have to deal with is a 2" or maybe 3" (prop shaft log?) hole in the hull or a broken hose or burned through exhaust hose.

I know every single one of the 19 holes in the bottom of my boat like the back of my hand, and every one of them is reachable without ripping out any cabinets. I could find them in the dark, if necessary. I have a large collection of wooden plugs and a mallet under my companionway, where I could find them even in the dark.

What I need to add to that collection is a waterproof head torch and a scuba mask -- note to self.

So the plan would be to get the pumps going to control the water level, then find the damned hole and plug it. If I have an AC electric trash pump, I guess that could be rigged in under a minute. Pull up the sole plate, plug in the cord, unroll the discharge hose, throw it out a hatch, start up the generator. The great thing about a real trash pump, as opposed to a mere dewatering pump, is that it will suck up and throw out most any crap which is floating around in the bilge.

A holed hose would be dealt with by turning off the appropriate sea cock -- and I keep all of mine well exercised by turning them all off every time I leave the boat -- so I know they all work.

In case of a hull breach, I would strike my staysail on deck, rig lines at all three corners, and try to get it onto the hull from the outside. But I think this is extremely unlikely -- if my hull gets breached at all, I think it would take a major catastrophic event which would crush it altogether, in which case the boat is going down and attention turns to abandoning ship.
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Old 30-10-2012, 07:41   #13
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Re: Crash Pumps?

First thing, to my mind, is to separate your A/c and genset from any flood water (allowing slop).
Comments above 'Jeremiason' make sense, consider that.
The real thing is fire will drive you off the boat, escape plan for that also covers sinking. Is it good enough. And can you use a bilge pump to make a fire pump? Couple of valves on a seacock should do it.
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Old 30-10-2012, 07:59   #14
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Re: Crash Pumps?

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Originally Posted by Dockhead View Post
Well, you can't keep the gasoline pump inside the boat where the gasoline fumes can get into the bilge. So where do you keep it? In the anchor locker?

Besides that, a rarely used gasoline engine is susceptible to having a gummed-up carburetor. I guess you could start it up, run it, then drain the carb, etc., etc. -- seems like a lot of trouble. What if you don't happen to have a full gas can on board to fuel it? etc., etc. Really doesn't seem like a good solution to me.

I would rather rely on my diesel genset, which is mounted above the water line, and which is backed up by main engine driving the inverter, and could even be run off my battery bank.
)
Another question is the hose -- will such a pump produce an adequate flow against a firehose-type flat hose? The head will not be all that great -- less than 2 meters, I think. But I've never used that type of hose so I don't know what kind of force is needed to overcome the flatness. All I know is that they sell this type of hose together with these pumps.

One more point: The WX10 Honda pump only pumps 37 gallons per minute -- less than my Rule bilge pump. A nearer equivalent to the electric pump I found is the WB20, which is, indeed, inexpensive, but weighs 47 pounds and looks to be quite bulky.
Dockhead,
Yes to storing in the anchor locker. As far as reliability it is certainly an issue. When the CG flies over in a C130 it is a small gas dewatering pump that they drop. While the rating on the smaller pumps are not huge, I suspect they are a lot more real than the marketing ratings on bilge pumps or the installed actual capability of bilge pump. The WX 15 only weighs 20 lbs and is rated at 72 gph. In my mind on a cruising boat a crash pump is something that is there for the extreme case when the basic boat systems aren't working to do the job. Relying on a genseta small boat is relying on the electric system, the fuel system and the electric pumps. It is not much of a stretch to think one of these has failed in a major holing. The small gas pumps are mostly self contained except a 2 gal jerry of gas. They are very competively priced compared to any permenant install. The engine mointed crash pumps look promising but are expensive to buy and even more expensive to install. $400 for a Honda pump is pretty reasonable.
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Old 30-10-2012, 08:13   #15
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Re: Crash Pumps?

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Originally Posted by Paul L View Post
Dockhead,
Yes to storing in the anchor locker. As far as reliability it is certainly an issue. When the CG flies over in a C130 it is a small gas dewatering pump that they drop. While the rating on the smaller pumps are not huge, I suspect they are a lot more real than the marketing ratings on bilge pumps or the installed actual capability of bilge pump. The WX 15 only weighs 20 lbs and is rated at 72 gph. In my mind on a cruising boat a crash pump is something that is there for the extreme case when the basic boat systems aren't working to do the job. Relying on a genseta small boat is relying on the electric system, the fuel system and the electric pumps. It is not much of a stretch to think one of these has failed in a major holing. The small gas pumps are mostly self contained except a 2 gal jerry of gas. They are very competively priced compared to any permenant install. The engine mointed crash pumps look promising but are expensive to buy and even more expensive to install. $400 for a Honda pump is pretty reasonable.
Well, the WX15 is still small potatoes in capacity terms 72 gph versus 150 gph for the WSP100 electric trash pump. But worse than that, the WX15 is not a trash pump -- it will not deal with solids. For that in a gasoline powered pump you need the WT20, which costs $1500 and weighs 104 pounds dry and will definitely not fit in my anchor locker.

Anyway, how long will a gasoline pump survive living in the anchor locker, even if it would fit? Not long, I'm sure. Will it start when you really need it? Doubtful.

The electric pump with the same capacity as the WT20 -- and the same trash-handling ability -- costs $800 and can live in the bilge. I would be much more confident that my diesel genset would start than any rarely used gasoline engine because I am using it every day. I think it would run even if it is partially submerged, and I can't think of any holing scenario which would affect the fuel system. The genset start battery lives well above the waterline. The potentially vulnerable thing is the AC electrical system -- and for that I guess it would be useful to have a disconnect switch and a separate outlet. The genset electrical control box is located on top of my genset -- far above the waterline.

Now a DIESEL powered trash pump might be a different proposition -- that you could keep inside somewhere, and is much more likely to start since there's no carb to gum up. But I don't know of one which is realistic in size.
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