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rachelthemoo
01-18-2010, 10:53 AM
Why are bilge pumps a safety requirement? I know this seems like a no brainer, but realistically if you get a hole in the hull, water will come in at a huge rate that the little bilge pumps required in the rules (manual, at least 10 gallons per minute) will not keep up with. One estimate I read, while googling, suggested 75 gal/minute would come in through the hole left behind if you lose your propellor shaft. 1 or 2 manual bilge pumps that pump 10 gal/minute will be near useless. Also, if you are a singlehander, the manual bilge pumps will be especially useless because likely you will be very busy trying to stop the leak or abandon ship. So if this is why we require bilge pumps, why do we not require bigger and electric bilge pumps?

Maybe the bilge pumps are required in the event that you stop the leak and now need to drain the boat? Or you stopped the leak imperfectly so need to frequently drain the bilge? Or just as a comfort measure for all the water that gets inside with normal sailing? And at least one manual bilge pump makes sense, in case you flood and lose the batteries.

But why is at least one strong electric bilge pump not required to help keep us afloat in case of a hole? Sure it would weigh down the boat, as would the battery(ies) to power it. But if we are supposed to be autonomous out there, shouldn't this be what we sail with?

I suspect that many of the larger boats have big electric bilge pumps. But I sure don't have one on my 27 foot boat. And I suspect that most little boats also do not have a big electric bilge pump, nor positive floatation, and in case of a big or little hole in the hull will depend only on a life raft, epirb, and sat phone. Is this not irresponsible?

Thanks for your thoughts!

Rachel
"Great White"

solosailor
01-18-2010, 11:01 AM
Well the requirement are the 'minimum'.... most folks do more.


I suspect that many of the larger boats have big electric bilge pumps. But I sure don't have one on my 27 foot boat. And I suspect that most little boats also do not have a big electric bilge pump, nor positive floatation, and in case of a big or little hole in the hull will depend only on a life raft, epirb, and sat phone. Is this not irresponsible?Why is it irresponsible to carry a bilge pump? Or do you mean it's irresponsible not to have more? Either way the requirement is meant to give you mean to empty water from your boat once you have stopped the ingress of water. No pump will 'keep up' with a holed boat, etc.

Anyway, since you are doing the Pacific Cup, not the SHTP..... what are their rules regarding pumps?

rachelthemoo
01-18-2010, 11:05 AM
Pac Cup rules based on ISAF 2008 Offshore Special Regs Cat 1 specify 2 manual bilge pumps. Strength is not specified. In contrast, SSS Transpac rules at least specify a minimum, though pitiful, strength of 10 gal/minutes.

Glad to hear that most people use stronger bilge pumps. What are you guys using for bilge pumps? Would especially love to hear about the smaller boats.

Rachel

John Hayward
01-18-2010, 01:24 PM
I have 3 manual and 2 electric. If the rudder or keel is knocked off, they will be useless except to give me slightly more time to abandon ship in an orderly fashion. In the event of a smaller leak like a through hull, crack in the hull or even a big opening in the deck in bad weather. they will allow me access to the area for repairs without diving gear. Finally, once the leak is fixed, I would rather clear the water in side the boat with a bilge pump than carting buckets up the companionway to toss over the side. Believe me, if you have ever gone down the companionway steps and seen water sloshing well over the floorboards you will *wish* you had a bilge pump if you don't.

John
Dream Chaser

Oceanslogic
01-18-2010, 04:07 PM
Hi Rachel..
Just my two cents...
"Blue Moon" my little International Folkboat will be equipped with two manual bilge pumps...one in the cockpit (Whale Gusher 10 Mk3) ...one down below (Whale Gusher 10 Mk3)...and an Electric pump installed but will see very little use. What is your setup going to look like for Great White?

tiger beetle
01-18-2010, 07:26 PM
Glad to hear that most people use stronger bilge pumps. What are you guys using for bilge pumps? Would especially love to hear about the smaller boats.

Beetle has three bilge pumps, none are electric, all are 10 gal/minute pumps. Most importantly, one is mounted at the nav station and has a 25 foot length of hose that can be lead to any compartment in the boat - I can pump out water while staying in communication via the radios (which are right next to the pump). I've done this while pulling out several hundred gallons of water that magically materialized beyond the forward ring frame - a total mess, and ultimately nothing bad happened.

Do not assume the pump required by the rules is intended to keep the boat afloat despite water ingress from a one inch hole below the waterline. If you're serious about de-watering a boat you're looking at a 2" diameter engine-driven trash pump that can push 200+ gallons per MINUTE (that's 12,000 gallons/hour). I'm not aware of any SSS boat that has sailed with one (though several such pumps are available).

The rule is a minimum - it will help deal with small leaks and maybe keep the boat more dry. If you develop a serious hole below the waterline a small hand-operated pump will not help - you MUST stop the leak first, and then use the pump to empty out the water.

- rob/beetle

Culebra
01-22-2010, 11:49 PM
A lot of ifs here... If large volumes of water must be pumped out fast, and if the engine will still start, one could close the raw water intake, disconnect the hose from the thru hull and lay it in the bilge, start the engine and pump the water out through the exhaust. I'm not sure what the rate of discharge would be, and I've never tried it. I don't think I want to intentionally practice it either. But it's a plan I keep in mind, just in case.

Paul

tiger beetle
01-23-2010, 11:18 AM
A lot of ifs here... If large volumes of water must be pumped out fast, and if the engine will still start, one could close the raw water intake, disconnect the hose from the thru hull and lay it in the bilge, start the engine and pump the water out through the exhaust. I'm not sure what the rate of discharge would be, and I've never tried it. I don't think I want to intentionally practice it either. But it's a plan I keep in mind, just in case.

Paul

You have a good plan; there is a slight difference between the engine raw water pump and a trash pump - a trash pump is designed to pass fairly large solids without failing or blocking up, whereas the engine's raw water pump is pushing the exhaust side through the engine's heat exchanger, which has a lot of small restrictions in place that tend to collect trash and eventually block the pump's output. If you have a strainer between the engine intake thru-hull and the raw water pump, then the strainer should prevent debris from getting into the heat exchanger (and you can theoretically clean the strainer periodically), and the strainer also restricts water flow. An engine-driven mechanical clutch control 2" trash pump will push more water than the engine's raw water pump - so it's something I've been eyeing for some time now. Haven't actually purchased one, but there are at least two such pumps that could be made to fit in the motor box and be belt-driven by the crank shaft take-off.

- rob/beetle

haulback
01-23-2010, 06:49 PM
Another simpler approach, is to buy a larger volume bilge pump 3500 - 4000 GPH - 2 alligator clips, some wire, and a length of 1 1/2" or 2" hose

You can either mount it in place permanently with a switch and a suitable thru- hull above the waterline, or carry it as an emergency pump to be rigged as/and/when.

I carry one of these (coiled up and ready to go - I can just throw the end of the hose overboard) in the hope the only use it will be is on some else's boat

My chosen complement of permanent bilge pumps is..... a manual one at the helm (10+ gals (depending on how scared you are, I suppose) a 1000 gph in the deepest part of the bilge, and a 3000gph mounted a foot or so below the cabin sole.

Will they stop me from sinking....maybe / maybe not - who knows. But they will more than likely buy me at least a little time to see to stopping ingress of water.

Personally, If I were taking on a whack of water at a great rate of speed, I would not be particularly interested in spending much time talking on the radio......I would be trying to save the boat first.

Jim/Haulback

haulback
01-24-2010, 10:35 AM
to continue previous thought.........

But I guess once it became obvious I was losing the battle, I would try to get a couple calls out before crawling into the liferaft.

Advantage of several electric/mechanical pumps plumbed independently of one another would have to be that they can all push water over the side at the same time. This allows you to move about the boat to locate and attempt to block a hole, while either keeping up with, or falling behind less quickly, the inflow of ocean.

Tough to pump more than one manual pump at a time.

Harder yet to make a repair while attached to a pump handle.

Jim/Haulback