2" trash pump as a crash pump?

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

swampu

Guru
Commercial Member
Joined
Jul 25, 2011
Messages
1,384
Location
USA
Vessel Name
Cajun Rose
Vessel Make
Biloxi Lugger
Hey ya'll, I'm still tinkering with the "Rose". I should get the port motor cleared soon and be moving around after 5 long years.
I had a question, the DD6-71's had a belt driven pump (jabsco) that I disconnected the plumbing during my rebuild. I was considering installing a 2" trash pump (gasoline) and plumb it for the all important crash or prop drop or whatever. What do you think?
 
1) why not reconnect the plumbing to the DD?
2) can't have too many pumps IMO. You might ask around town down there and see if you can find a used diesel one. I wouldn't "plumb" that trash pump if at all practical; better to be able to use it as close to the source of the leak as possible.
 
I would not want to count on any infrequently used, small gas engine starting in an emergency. I bought a submersible 110 volt trash pump for emergencies. I can run it off the inverter until I start the generator and keep pumping until I run out of diesel. It seems like a much better idea than pulling on a cord while the boat is sinking.

This is what I am bought: Tsurumi Pump HS2.4S-62 Tsurumi - 53 GPM 2-Inch Submersible Trash Pump
 
Hey Paul. More pumps and pumping options are always welcome and the Rose has plenty of room for them. If you "plumb" it in right, you will still be able to move it around in an emergency. Just make sure your first fittings on the pump are quick connect style.
 
I'm with SteveD on this one. A small gasoline engine isn't likely to start when you need it to. There are lots of other options. Electric as Steve suggests. Propane engines store well without frequent use. Belt drive off your main engines. Use the raw water cooling pumps on your engines to pump the bilge.
 
Along my list of planned future upgrades is to setup a way for the main engine to be fed raw water from inside the boat. Should water come in for some reason, rev up the main to help pump out. Haven't thought it all out yet, but that was the basic idea.
 
Our DD has a Y in the main raw water pump suction line which just needs to be opened to act as emergency pump. Simple but assumes you can reach the valve.
 
Here's a pump I bought from Harbor Freight to use to remove water from the pool. I don't think there's a reason why this couldn't be used in a bilge as an emergency pump. 110V, 3/5 hp, 2110 GPH for $52.

image_20279.jpg
 
I kept a Simar pump like GFC pictures on the boat that came in very handy. The Whaler got swamped once by a weird combination of events, and the Hatteras had a mystery "bilge" I discovered that had no drainage that filled up when we had a freshwater leak (an old Hatteras hand fixed that one eventually).

As for the gas engine pump, its reliability is a function of maintaining and running it on a scheduled basis.

As for pumps driven by a Y to the main engine raw water pump, in reality that is a hard system to make work. First, as noted previously you have to get down there and make the switch. Then you have to monitor it so that the engine doesn't run out of raw water cooling. All this while dealing with a bad leak in who knows what kind of circumstances (and these things rarely happen in benign circumstances).

The first move to bolster pumpage should be to install high water bilge pumps to back up the every day pumps. Dave Pascoe has a good "how to" article on this on one of his sites. The Hatteras had three sumps that were serviced by standard 2000gph bilge pumps, and those sumps flooded if the adjacent bilge over flowed. Still, a high capacity high water bilge pump here and there was well advised.
 
As for pumps driven by a Y to the main engine raw water pump, in reality that is a hard system to make work.

I don't see it. There's always two of us onboard, if not more. High water alarm goes off, go down and look, see water, open y valve, plug hole. Close Y valve.

To the the issue of "you have to get there first." You bet! There's water coming in I'll be down there to determine if we are staying afloat or not.

This is all theory, I've never been in a situation where I've had to use this, if someone has I would love to learn from your experience.

For us this upgrade is insurance against failure in a thru hull. With most thru hulls inside the engine room it made sense to put the additional pump there. The advantage of this setup is its independence from the electrical system which we like as the batteries are low in the hull.
 
I really believe in having a lot of pump capacity. It buys you time to slow or fix the leak.


I was once on a fishing boat that backed down on a fish so long that enough water came aboard that the freeing ports stayed submerged. When we realized what was happening we were able to stuff towels in the ports and slow the inflow to where the onboard pumps could hold the level until the Coast Guard arrived with a nice big 3" crash pump. With that we were able to get ahead of the water and bring the freeing ports above water.


During the emergency I was asked to monitor the water level. Down in the engine room, water half way to my knees, I kept staring at the two big beautiful Jabsco pumps on the engines. I was thinking that if it got any worse, I'd try to cut the hose connected to the seacock. My own boat is rigged to easily pump the bilge with the engine. It's only an 1-1/4" pump but it moves significant water. The bigger the engine/pump, the more worthwhile it is to do this.
 
No Mast, You asked if anyone had used the M/E raw water system to pump a sinking boat. I have, twice, old surplus wooden boats many years ago one sprung 2 planks in rough weather the other pulled out a strut when it hit a log. It worked fine and simple as dirt. Large volume jabsco, 2 ball valves a T, piece of reinforced hose and a flat shoe strainer. If the bilge water is dropping you're good to go if it's still rising your not. I also like a trash pump stowed topside with enough suction hose to reach my deep bilge. This allows pumping someone else's boat in an emergency and with proper fittings can be used as a fire pump. Bill
 
I wonder how many of you questioning the reliability of the gas engine pumps use them on a regular basis? Sorry, silly question. I'm quite sure all of you do :)

The last one that failed to start for me was driven over by an excavator.
 
Start a Honda trash pump once a month, run it free of fuel and it will start religiously for years on the first or second pull.

Use fresh fuel every 4 months or so.

Even rusty, neglected,, stored in the bilge, ect ...etc....

We use them in salvage work and they are workhorses.

Safe to store with no fuel in them.

Use a small fuel tank stored above decks with a quick disconnect.
 
I've been involved in using a main engine system twice--- both times were practice drills ( a necessity). The key was finding the hole. Instructor/captain either had run a hose to an obscure spot or wouldn't tell you where the non-existant hole was until you "found" it. Then told you the nature of the "hole" and you had to go fetch a suitable "plug". In at least one case every session, the hole wasn't the issue, non-functioning "regular" bilge pumps were. So here the danger was even more so that the ME pump emptied the water and now the ME had no raw water supply. Oh, and it's possibly being gunned to run up on the nearest beach if one's available. And so on with many variations.

I guess it is human nature to imagine that any emergency is going to take place in ideal conditions... in this case no steam filling the ER from water meeting hot iron , no smoke from shorted or failed electrical issues (which is why the pumps didn't work), etc.

I'm not saying ME raw water Y valve set ups are no good, but they are not a simple panacea, and if you don't have a plan and practice, can be dangerous and expensive.
 
Thanks guys, I never thought about usinging it as a fire pump or helping someone else! That's very narrow minded of me. I think it would be dumb not to plumb the existing engine run pumps and have the 2" as a backup. Thanks
 
Remember the key is plugging a leak. A 2" hole 3 feet under the waterline will produce over 14,000 gph (235 gpm) into the boat.
 
Remember the key is plugging a leak. A 2" hole 3 feet under the waterline will produce over 14,000 gph (235 gpm) into the boat.

I think it's just over half that (135 gpm)

Chart for Determining Flow of Water Through Holes in Gallons Per Minute
Flooding.html

However - it's still a huge amount of water. For my trip back from Alaska we rigged a 3700gph bilge pump with a long hose and power leads with alligator clips. It's in the engine room since that's where the batteries are and that's the most important bilge to protect. The idea is just to drop the pump into the bilge and throw the hose overboard and hook up to one of the 6 8D batteries in the engine room. Still, that's only another 60gpm.

The truth is, if I were to suffer a 2" hole in the hull, my chances of finding and plugging it would be slim unless it was in the forward third of the boat. There is so much tankage and other equipment that I would be lucky to find and plug the hole in time. Even in the forward section of the boat it would mean crawling beneath the sole in a very tight area that was rapidly filling with water.

In practice, the most likely failure would be a through hull - and I know where all of those are.

Scary when you start to think about it a lot.

Richard
 
A better method would be a fastflow bilge pump on the engines. They run constantly, as long as the engine is running, and running dry does not harm them. They are high volume pumps that once the water gets to their level, it will help stem the flow until you run out of diesel.

One way to use them is to have them on the prop shaft but that assumes you're in gear.

The shaft version splits so you don't have to pull the shaft to install them.

Stu
 
Another pump on my boat is the holding tank dump pump. I have aY on the inlet side. Y fwd is to empty the Holding tank, Y aft is to suck from the bilge. I have a square, flat sucker end so that this pump can take the bilgewater down to 1/4" deep, whereas the Rule pumps elsewhere in the bilge can only get it down to 1.5" deep, or so. Not a huge capacity in an emergency, but every little bit helps.
I also carry a crash pump, 2". I have used it to wash off the docks, help other guys, and once, to drain a high water event in my own bilge. Works good, lives up top, in the open air, under a blue canvas cover, so nobody sees the rust but me. It helps to run it on a regular basis, so you know the ethanol hasn't ruined the gas in its tiny tank. I also try to fill with premium gas when I can, as I do with all of my small gas engines, just to limit the ethanol damage.
 
Not in all collision cases do you want to be underway....thus a shaft bolt on pump is nice but still only a piece of the puzzle.

Usually it will take a collision or some kind of hull breach to beat a 2 inch trash pump. Sure a failed sea cock...but reasonable maintenance should beat that issue.
 
I think it's just over half that (135 gpm)

Chart for Determining Flow of Water Through Holes in Gallons Per Minute
Flooding.html

However - it's still a huge amount of water. For my trip back from Alaska we rigged a 3700gph bilge pump with a long hose and power leads with alligator clips. It's in the engine room since that's where the batteries are and that's the most important bilge to protect. The idea is just to drop the pump into the bilge and throw the hose overboard and hook up to one of the 6 8D batteries in the engine room. Still, that's only another 60gpm.

The truth is, if I were to suffer a 2" hole in the hull, my chances of finding and plugging it would be slim unless it was in the forward third of the boat. There is so much tankage and other equipment that I would be lucky to find and plug the hole in time. Even in the forward section of the boat it would mean crawling beneath the sole in a very tight area that was rapidly filling with water.

In practice, the most likely failure would be a through hull - and I know where all of those are.

Scary when you start to think about it a lot.

Richard

Your probably correct. 235 just sounds to high. HTFF classes were too long ago and I am to lazy to go figure out Mr. Bernolli's equation.
Dave
 
My concept...if not the concept of all damage control isn't necessarily stopping all leakage....just reducing it below pumping capacity.

As long as it's enough to gain on the level and start better repairs.
 
Back
Top Bottom