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Random Quote: Yield to temptation, it may not pass your way again LL
The 32 Luhrs thread was headed in a direction of discussion regarding crash valves. Not wanting to hijack the thread I decided to share this photo.
See the manifold on the left of the bulkhead. It looks a little like a sprinkler manifold. This setup was on a custom 46 Hat I did a little while ago and found pretty impressive.
The black valves on both ends are suction lines from the engine water supplies. They are plumbed to ball valves and T fittings at the sea valves. The red valves are plumbed to the four bilges and terminate in heavy bronze bilge strainers.
This thing is well thought out and very functional in that you can pump any bilge from either engine. I can look through the file for more detailed photos if requested but I think you can the get the basic idea from this.
"better safe than soggy" Quote from Capt. Jody Weis.
__________________ Baitkiller= Accredited Marine Surveyor
Bait fear me, fish just laugh.....
The little Dutch boy was just buying time...
This is a nice idea, and well implemented. I have also been thinking about this since that luhrs 32 thread. I realized that although I do have 5 bilge pumps, they are all the 1000 gph pumps, and, if faced with a serious flow of water, I don't think they will fill the bill. I would agree that this is the upper echelon of designs, and overall, I don't think this would be that tough to install... really the toughest element would be adding the T into the main water intake.. What is the best, safest, and most long lasting way to put a T into the main line??? are we looking at a simple clamp setup or something more involved???
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Lets have a Sexy Party! 38 Henriques FB 2000 ~ 17 Montauk 1978
Great idea and well done, only negative is the valves themselves. I had those on my pool filter and they got pretty tight after a few years. Having one of those plastic red handles break during an emergency would not be a good thing. Now where they are there will be no UV issues, just engine room heat. Upgrade the valves and it would be perfect.
I would have to agree with obbayer... If I was going to do it, I would have all brass valves in there and no plastic, and I would put the same intake hose on those lines as I had on my thru hulls.... Anything worth doing is worth overkilling.
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Lets have a Sexy Party! 38 Henriques FB 2000 ~ 17 Montauk 1978
I agree about the PVC being a little "sketchy" for the job, but the PVC valves have very high flow rates for their size. The holes through the balls in brass valves are usually smaller and don't flow as much.
"I would have to agree with obbayer... If I was going to do it, I would have all brass valves in there and no plastic, and I would put the same intake hose on those lines as I had on my thru hulls.... Anything worth doing is worth overkilling.
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Knot Reel Teeth 38' Henriques "
This is way too close to salt water for brass, I think those are scheduled 40 valve's, I think I'd be comfortable with the entire manifold done in schedule 80 PVC. An upgrade from there would be a bronze manifold and full flow bronze ball valves ( available but more expensive than the small hole valves kerno was referring to).
"I would have to agree with obbayer... If I was going to do it, I would have all brass valves in there and no plastic, and I would put the same intake hose on those lines as I had on my thru hulls.... Anything worth doing is worth overkilling.
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Knot Reel Teeth 38' Henriques "
This is way too close to salt water for brass, I think those are scheduled 40 valve's, I think I'd be comfortable with the entire manifold done in schedule 80 PVC. An upgrade from there would be a bronze manifold and full flow bronze ball valves ( available but more expensive than the small hole valves kerno was referring to).
My mistake on that one... I was a bit fuzzy writing that reply last night I did in fact mean bronze. My apologies. In regards to the PVC, it seems to me that there would be a great deal of force exerted on such a valve... Would PVC be appropriate on a larger diesel engine I really don't know what the tolerances are, but I would stand by my original post and say anything worth doing is worth overkilling... Also, I am curious as to how one would setup the T valve in the main raw water intake line... would it be better to bolt on a bronze or SS T bold to the seacock and have the flex line off that, or to split your flex line and place the T in the middle???
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Lets have a Sexy Party! 38 Henriques FB 2000 ~ 17 Montauk 1978
There was a discussion on this subject on another forum recently.
The drawback to this type of system (near as I can tell) is the fact that it's operation depends on valve adjustments.
Seems like you would need someone familiar with the system at the manifold constantly "tweaking" the valves in the event you needed to use the system.
If you shut the raw water off at the seacock and open one or more of the bilge strainers, you run the risk of running the bilge dry and burning up the impeller(s) and overheating the engine(s). Those 8V92's pull a lot of water. That looks like only 3/4" or maybe 1" PVC at the most, I don't know that it could handle the flow rate necessary for even one of the engines, or to evacuate the amount of water necessary in the event of a hull breach.
If you don't open the valves enough, the water level in the bilge will continue to rise.
I do agree it's worthwhile having, just pointing out a limitation as I see it.
There was a discussion on this subject on another forum recently.
The drawback to this type of system (near as I can tell) is the fact that it's operation depends on valve adjustments.
Seems like you would need someone familiar with the system at the manifold constantly "tweaking" the valves in the event you needed to use the system.
If you shut the raw water off at the seacock and open one or more of the bilge strainers, you run the risk of running the bilge dry and burning up the impeller(s) and overheating the engine(s). Those 8V92's pull a lot of water. That looks like only 3/4" or maybe 1" PVC at the most, I don't know that it could handle the flow rate necessary for even one of the engines, or to evacuate the amount of water necessary in the event of a hull breach.
If you don't open the valves enough, the water level in the bilge will continue to rise.
I do agree it's worthwhile having, just pointing out a limitation as I see it.
That's why, although the pvc manifold looks neat - it is far too small (looks like 1-1/2") to keep up with the engine; a better way to do it is to put a T on the strainer intake (assuming the engine intake valve is nearby) with a ball valve there, so that a crewmember can balance the flow between the two valves to keep water flowing to the engine while evacuating the bilge. If you've even seen a decent size diesel's raw water pump run, at 2000 rpm, it will pump many hundreds of gallons a minute - and not that optimistic bilge pump number - there's a reason they use a 3" intake hose - when your 2000 gph bilge pump only has 1-1/4" discharge hose.
As a different approach to this, has anyone seen, used, or heard of an Ericson Safety Pump?? This mounts to the driveshaft and can provide up to 12,500 gph of flow, and negates the worry of the valve... I found out about these today as I was doing some research into different ways to to rig the above mentioned rash pump, and I am thinking that this could be a good solution
Look at the Groco safety seacocks. I installed these on my boat. Easy to install and you can't beleve how easy it is to winterize the engines. Put the pick up into a bucket of anti-freeze, close the seacock to the outside water and open the value to the pickup line. Groco also makes a kit with the seacock, value and pickup strainer.
SBV-P SERIES
DIMENSIONS DRAWING
SBV-P Series
Full-Flow Flanged Safety Seacock
Two driver ports permit handle relocation.
NPT threaded side port accepts SSCV or any NPT threaded accessory.
Handle has square hold that accepts standard ratchet; helps access hard-to-reach valves, or ease actuation of hard-to-operate valves.
Full pipe-size flow.
Designed and manufactured for in-field serviceability.
Stainless steel ball and stem.
PTFEŽ seats and seals.
Base has provisions for bonding system attachment.
As a different approach to this, has anyone seen, used, or heard of an Ericson Safety Pump?? This mounts to the driveshaft and can provide up to 12,500 gph of flow, and negates the worry of the valve... I found out about these today as I was doing some research into different ways to to rig the above mentioned rash pump, and I am thinking that this could be a good solution
Well done, as there are a few other options that are available.
Obviously, safety systems onboad are most important in that they not only might safe your life but can help in insurance coverage.
Similar to the above style, when space permits high volume mechanical discharge pumps can be installed foward of a main engine and driven from the crank shaft. Either via belt and pulley or a drive shaft to crank(PTO). These equal having there own discharge which usually can have more capacity then that of the raw water pump.
So, all of that is good with the consideration that your engines remain operable. Going a step further, is the installation of a diesel fired indepenant pump system. These are used many times with ocean crossing or keel cooled dry stack systems. Even can be plumbed for fire fighting when allowed it's own water pick up.
The bottom line, hopefully any flooding water rate remains less than your discharge abillity.
crash valves 
I really don't know what the tolerances are, but I would stand by my original post and say anything worth doing is worth overkilling... Also, I am curious as to how one would setup the T valve in the main raw water intake line... would it be better to bolt on a bronze or SS T bold to the seacock and have the flex line off that, or to split your flex line and place the T in the middle??? 
