engines raw water pump emergency pumping

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Nordic Tug 37
whether some experience with the idea of ​​using the raw water pump is an emergency situation, empty the water out of the ship? The valve attached to the bottom and open the second line and valve that sucks pilssistä? second function of the second flushing valves / glycol driving winter maintenance.:confused:


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Small engine raw water pumps are often not many gph, especially at mid to lower range RPMs.
 
long time ago I saved a boat from sinking with engine raw water pump, a lot of water inside the Grand Banks all battery service under water so no move energy for bilge pump, by chance I started main engine crankshaft was under water you can imagine the emergency to pump aout, boat was a mooring.
when engine was started I cut hose near through hull and closed the valve... after that full RPM and Lehman and after 2 hours boat was back at live !

Any way installed a 3 way valve on the hose from through hull to engine are a very nice way

Hugues
 
I do not know how much of my Cummins qsb 380hp cooling water amount, but runs about 2,600 rmp it appears to be from the exhaust pipe of hard and pretty much...


boat bilge pumps (3) are reasonable, but woke up the idea if you ever become a real emergency water overflows. I keep trying to look at the pump return water per minute.
 
long time ago I saved a boat from sinking with engine raw water pump, a lot of water inside the Grand Banks all battery service under water so no move energy for bilge pump, by chance I started main engine crankshaft was under water you can imagine the emergency to pump aout, boat was a mooring.
when engine was started I cut hose near through hull and closed the valve... after that full RPM and Lehman and after 2 hours boat was back at live !

Any way installed a 3 way valve on the hose from through hull to engine are a very nice way

Hugues

:)great that you shared your unpleasant experience from which we can learn.

is a very easy and cheap to build it really basic rotating the pronce ball cock T. In addition to ease further to flush and run through the machine glycol winter storage. could be good to put a strainer end of the hose into certainty

 
:)great that you shared your unpleasant experience from which we can learn.

is a very easy and cheap to build it really basic rotating the pronce ball cock T. In addition to ease further to flush and run through the machine glycol winter storage. could be good to put a strainer end of the hose into certainty


Yes exactly that, I call 3 way valve :D
 
While the engine raw water pump may work in that application, they aren't designed to overcome significant head vacuum and frictional line loss (long suction hose). Most high volume boat pumps are designed to push water not suck or lift it. If I were going to build that setup, I would run some tests first to see how well my engine pump worked in that application. Remember, water in the bilge may be significantly lower than the water surrounding the boat, tougher for the pump to prime and pull. A very large strainer on the bilge end of the hose would be a good idea also.

Ted
 
whether some experience with the idea of ​​using the raw water pump is an emergency situation, empty the water out of the ship? The valve attached to the bottom and open the second line and valve that sucks pilssistä? second function of the second flushing valves / glycol driving winter maintenance.:confused:


We have those (SSC fittings) on the seawater intakes on both mains and the AC pump.

Haven't yet had to test the "emergency pumping" function, but watching the way everything works during maintenance flushes, seems to me it'd work OK.

Thoughts:

- removing the fixed plug and inserting the flush adapter allows some drippage, to varying degrees, during the changeover (I've talked with the Groco guy about a version with the adapter fitting more permanently mounted, perhaps with a valve. No perfect answer to that, yet. Something can be cobbled together... but I've not yet become comfortable with the various ideas so far. See crash valves, below.)

- on larger units (like for our mains), flow is restricted, compared to the mainstream flow

- The flush adapter is necessarily higher off the bilge floor, which would mean it takes LOTS more water inside before it'll start picking up (unless also used with a hose and filter; see below)

- Groco's real crash valves would be better (see SBV series). This is the one with a selection handle so changeover is instantaneous; no drippage assuming attachments are already mounted onto the engine room side

- either option would be best augmented with a hose and strainer (Groco has strainers, too, see BS/BSA series); couple with the flush adapter, the hose would also mitigate the height problem

-Chris
 
Yes it works. And works pretty in many cases.

I saved a boat from sinking by doing just what 101 TUG described.

The simple way to set it up is to install a T valve in the raw water line to the engine between the strainer and pump. Coming off the T you have a hose going to the bilge with a strainer foot on the end of it.

That way all you have to do is throw the valve to start pumping out the bilge.
 
The simple way to set it up is to install a T valve in the raw water line to the engine between the strainer and pump. Coming off the T you have a hose going to the bilge with a strainer foot on the end of it.

That way all you have to do is throw the valve to start pumping out the bilge.


That reminds me, I should have mentioned our SSCs are installed immediately after the thru-hulls, before the hose that leads to the strainers.

That just happened to be where we had the most room to work with, no tight bends to deal with... otherwise could have added them after the strainers instead. OTOH, installing before the strainers also allows cleaning fluid/antifreeze flushes that treat the strainers at the same time, too.

-Chris
 
I think in real life, the chances of an engine driven pump saving the day are pretty rare. I have a hose I can unhook between engine and strainer and it is the right length and position to flop down into the bilge. But unless you rev engine up, it really is not moving much water. The chances of a leak being that small, yet threatening the vessel, seems unlikely.

I set up my rig with four mostly water tight bilges. All penetrations in the overhead, none in the bilge. Between fwd and cabin bilges, only low penetration is a door, and it fits pretty snug and I can screw it closed if need be. What leaks past then would be minimal.

Four 2000gph bilge pumps, two are on house bank, two are on start bank. Also shower sump will pump if it gets submerged.

Never understood why rec boats typically do not separate bilges between compartments.
 
This is the setup on many Viking sportfish. The paper towels are on the handle for the seacock. Below the gate valve is a bronze strainer to keep the big chunks out.
CrashValves.jpg
 
Personally...

I think that early detection through the use of a high bilge water alarm, coupled with a high flow 120 volt pump at 3600gph or thereabouts would buy you time and possibly save your boat.

The trick is knowing you have a high water situation before it gets out of hand.

Having an alarm go off and a pump automatically activated is in my opinion much better than having to crawl into a engine space that is flooding, and doing anything.

If you add into the equation that short of a colision the most likely cuse of a flooding situation involves one of my engines 2" seawater systems, an engine driven pump becomes less useful the more I think about it.
 
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It's interesting that you guys are considering using the engine cooling pump for emergency dewatering. I've had this discussion over on the Cruisers Forum. Those guys are mostly sailors. They are very against it saying you might damage the engine and it doesn't move much water anyway.

The idea of worrying about the engine while the boat is sinking strikes me as silly.
Their pumps are smaller than ours so they may have a point about the low capacity.

I have a tee fitting on the intake side of my sea strainer. One leg goes to the seacock, the other leg goes to a ball valve and hose into the bilge. In an emergency I can open the ball valve, close the seacock and I'm pumping an extra 1000 gph or more overboard.

I was once on a sinking boat that had two nice big 2" cooling pumps that would have required me to cut the intake hoses to use for bilge pumping. The Coast Guard arrived before I tried that.

If anybody says that a scared man with a bucket is the best bilge pump, I fart in your direction:D
 
Yes it works. And works pretty in many cases.

I saved a boat from sinking by doing just what 101 TUG described.

The simple way to set it up is to install a T valve in the raw water line to the engine between the strainer and pump. Coming off the T you have a hose going to the bilge with a strainer foot on the end of it.

That way all you have to do is throw the valve to start pumping out the bilge.


Do you mean throw two valves? I am not able to picture a strainer foot that would not allow air into the system without a valve in addition to thru-hull
 
Do you mean throw two valves? I am not able to picture a strainer foot that would not allow air into the system without a valve in addition to thru-hull

You need a valve in the emergency pick up hose and the seacock.
First you open the valve in the emergency hose and then close the seacock.

This is my set up with the emergency valve in the open position. Note that I used a quick connect fitting on the emergency pick up hose.
 

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It may suprise a few here...but the actual number of boats that actually sink compared to those that call a "taking on water" mayday is not even close in my experience.

Many boats I have responded dedicated to had nothing more than a fresh water line let go, or a rough water condition pumping water into the boat that stopped once the boat stopped, changed course or the engine drowned, or too much spray for the mostly not working bilge pumps......


If you cook your engine for anyone of these situations...it may haunt you a bit.

I think using crash valves that use properly strained bilge intakes to use the engine raw water pumps is a great idea...as long as the engine water pump will make any kind of difference. For many that have 120hp or less engines...I would double check the raw water pump output at mid to low rpm before I spent any money or energy doing the conversion.

When I had a pair of 3208 Cats in my sportfish...sure I had plans for using those engine pumps as emergency crash pumps. But heck, 2 pumps and impellers as big as my fist and 3X the size of my Lehmans, I certainly expected better results.
 
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It may suprise a few here...but the actual number of boats that actually sink compared to those that call a "taking on water" mayday is not even close in my experience.

Many boats I have responded dedicated to had nothing more than a fresh water line let go, or a rough water condition pumping water into the boat that stopped once the boat stopped, changed course or the engine drowned, or too much spray for the mostly not working bilge pumps......


If you cook your engine for anyone of these situations...it may haunt you a bit.

I think using crash valves that use properly strained bilge intakes to use the engine raw water pumps is a great idea...as long as the engine water pump will make any kind of difference. For many that have 120hp or less engines...I would double check the raw water pump output at mid to low rpm before I spent any money or energy doing the conversion.

When I had a pair of 3208 Cats in my sportfish...sure I had plans for using those engine pumps as emergency crash pumps. But heck, 2 pumps and impellers as big as my fist and 3X the size of my Lehmans, I certainly expected better results.

My JD 4045 raw water pump is 35 GPM at max RPM. Each of my big bilge pumps is 160% of that. They also aren't pushing the water through 2 heat exchangers.

Ted
 
same on our boat the system to pump bilge water with main engines is from original build
MAN R6-800 is 100GPM so with 2 engines 200GPM total

Good last chance solution

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My JD 4045 raw water pump is 35 GPM at max RPM. Each of my big bilge pumps is 160% of that. They also aren't pushing the water through 2 heat exchangers.

Ted

Do you have monster bilge pumps? I am just comparing directly (visually) the volume my electric bilge pumps are outputting vs. what's coming out of the exhaust at idle and its really no contest. Raw water pumps are winning. Plus conceptually... the impeller size, hose size, and RPM.. not to mention just energy input... kinda wondering if GPM rating of bilge pumps are bogus?

EDIT: the last garden hose I measured was would fill a 5 gallon bucket in about 45 seconds, just for reference. 35gpm would be insane.
 
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I don't think my engines dump more than a few litres of water out of the exhaust pipe a minute. Add the potential harm to the engines of sucking up something that stops the flow altogether, when you are sucking from the bilge. Sure, some of us have nice, clean bilges, but add an uncontrolled flow of water into the bilge and stuff will get washed down and arrive at the sucking water intake.

What I have in my boat, is a Y valve on the macerator pump that discharges the holding tank. It is easily accessible and the other branch of the Y goes to a bilge pickup, complete with a screen that has 1/4" holes, so anything that gets through the pickup will get crunched in the macerator on its way out. The capacity of this pump is about 600 gph, so not sufficient by itself, but way better than what my engine cooling pickup could do and way safer.
 
it seems that in relation to money and work would be smart to build this simple emergency pump "last hope" possible before the sinking. Thanks for the pictures which made this system. # 17 image seimerkki easy to implement, and in time of need to open and close the second valve. I am thinking of is just the same at the point where the vessel sink begins to melt down raw water pump or it blocking the heat exchanger or the other. if the boat sinks must then be opened and repaired throughout the boats.

I have a bilge pump 3 x 700 gal / h, but it is not much even if the gland fails. from one medium to pronze valve under 1/1/2 foot depth of water will be about 1,600 gal of water in an hour. if a bigger hole that was it, and vessel sinks. I remember reading Nick Calender commented that the indicated power the electric pump is only about 50% of the declared virtually installed in the boat. and it is also possible that, they do not work, is congested, or decompose in doing so.

here in the Archipelago Sea is really able to get to the bottom of the hole when adventuring in places where there is no official route of ships. Also, if the base bushing breaks down, the water becomes hard and yes a lot.


three times I have received a grounding stone, fortunately, did not come to the bottom of the hole thanks to Solid laminated floor, I do not want to think about what shandwits the bottom. fiber glass disintegrated yes, but not holes and leaks.


Nice video how water come in and tips.
 
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Keith I like your idea about using the macerator pump. I hadn't thought of putting a Y valve in the intake.

You sound like one of those blow boat guys who would rather let their boat sink than risk overheating the engine. Don't get mad at me, I'm just poking a little fun.

Actually with a strum box on the pick up and running the water through the sea strainer, it's unlikely you'll overheat the engine.

How big is your engine? I bet the pump has at least a 1" hose on it and it can move close to a 1000 gph.

Bilge pumps are like time machines. The more pumping capacity you have, the more time you have to deal with the flooding.
 
Keith I like your idea about using the macerator pump. I hadn't thought of putting a Y valve in the intake.

You sound like one of those blow boat guys who would rather let their boat sink than risk overheating the engine. Don't get mad at me, I'm just poking a little fun.

Actually with a strum box on the pick up and running the water through the sea strainer, it's unlikely you'll overheat the engine.

How big is your engine? I bet the pump has at least a 1" hose on it and it can move close to a 1000 gph.

Bilge pumps are like time machines. The more pumping capacity you have, the more time you have to deal with the flooding.

Same washdovn pumps make this T-valve and hose bilg
 
What I have in my boat, is a Y valve on the macerator pump that discharges the holding tank. It is easily accessible and the other branch of the Y goes to a bilge pickup, complete with a screen that has 1/4" holes, so anything that gets through the pickup will get crunched in the macerator on its way out. The capacity of this pump is about 600 gph, so not sufficient by itself, but way better than what my engine cooling pickup could do and way safer.


Oh, my. Thanks for a great idea!

Happens our holding tank macerator pump has been crapped out (so to speak, sorry) for a few years now... I suspect mostly just from non-use. All the usual tricks -- manually spinning the axle, hammering on it, etc -- haven't worked...

But a Y-valve on the feeder to that pump's eventual replacement could do two more things for us: provide an easy (and legal) way to "rinse" (exercise) the pump periodically, and add a whole 'nother emergency pump-out capability in an underserved area in our boat. Of course it would also temporarily block sewage to the pump for future maintenance, but I'd already known about that.

Anyway, thanks for mentioning your set-up. Have a virtual beer on me! :)

-Chris
 
Do you have monster bilge pumps? I am just comparing directly (visually) the volume my electric bilge pumps are outputting vs. what's coming out of the exhaust at idle and its really no contest. Raw water pumps are winning. Plus conceptually... the impeller size, hose size, and RPM.. not to mention just energy input... kinda wondering if GPM rating of bilge pumps are bogus?

EDIT: the last garden hose I measured was would fill a 5 gallon bucket in about 45 seconds, just for reference. 35gpm would be insane.

Have 2 medium size pumps and 2 large size pumps. The medium are 30 GPM with a 1" discharge and the large are 60 GPM with a 1.5" discharge. Water running out the exhaust is deceptive, especially at idle. You can perceive it to look like a lot, but it's slower moving. Water being discharged from a bilge pump generally has a higher velocity. A similarly perceived volume at a significantly faster velocity can be several times more gallons per minute.

Ted
 
We are required by class regulations (Lloyds Register A100+) to have engine emergency suctions on our Cat3512"s.
Our Gilkes raw water pumps are about 3-4" suction & discharge, the stbd eng uses a straight into the bilge, valved off, suction.
The port engine, slightly different, has an electric clutched, belt driven 2" self priming centrifugal pump that takes a suction from the shipwide bilge suction manifold. And, it can also pull a sea water suction and discharge to the fire main system.
They are both required to be operational, and are tested by inspectors to meet regs on a regular basis.
 
We are required by class regulations (Lloyds Register A100+) to have engine emergency suctions on our Cat3512"s.
Our Gilkes raw water pumps are about 3-4" suction & discharge, the stbd eng uses a straight into the bilge, valved off, suction.
The port engine, slightly different, has an electric clutched, belt driven 2" self priming centrifugal pump that takes a suction from the shipwide bilge suction manifold. And, it can also pull a sea water suction and discharge to the fire main system.
They are both required to be operational, and are tested by inspectors to meet regs on a regular basis.

:thumb:thank you for sharing this information, to tell the effect on me that I will build my emergency solution to the raw water pump. why not make anything that can save you from unpleasant consequences, even if the need for any damages before a judge (the bilge Pump speed fuse)


I saw this member "Lepke" embarking on the debate "Marine Salvage and Insurance" thanks to him

https://www.workboat.com/blogs/maritime-matters/fortuity-and-the-bilge-pump/
 
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What I have in my boat, is a Y valve on the macerator pump that discharges the holding tank. It is easily accessible and the other branch of the Y goes to a bilge pickup, complete with a screen that has 1/4" holes, so anything that gets through the pickup will get crunched in the macerator on its way out. The capacity of this pump is about 600 gph, so not sufficient by itself, but way better than what my engine cooling pickup could do and way safer.


I agree with the others Kieth, this is a great idea. I will be checking to see if this might be possible on my boat. I only have one macerator pump but it would be better than nothing. It would be a good use of a pump that otherwise I have only used a couple of times. Since my waste discharge needs to be secured by n my home waters, a Y valve secured in the position to drain the bilge would keep me legal as well as provide some additional dewatering capacity.
 

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