How many bilge pumps?

[Na Mara]

I’ve often wondered at the wisdom of electrical bilge pumps run off the ships supply for dealing with hull breaches. Firstly, even the best of them won’t keep up with much more than a fitting leak. Secondly, the batteries on most boats are located low down for weight distribution which makes them vulnerable to flooding. When the electrical system fails you’re screwed. Finally, a fixed pump will only drain from one point in the hull.

It seems to me that the best solution is a petrol driven water pump or similar. Those can shift serious amounts of water a long way up hill, they will run for days, they can be moved to where you need them and they are independent of the boat’s electrical systems. You can buy a Honda that will shift 66000 lph for about 800 euro.

So why not have a manual pump, a rainwater electrical one on a float, and then a petrol beast for when TSHTF?

[rslifkin]

Originally Posted by Na Mara

I’ve often wondered at the wisdom of electrical bilge pumps run off the ships supply for dealing with hull breaches. Firstly, even the best of them won’t keep up with much more than a fitting leak. Secondly, the batteries on most boats are located low down for weight distribution which makes them vulnerable to flooding. When the electrical system fails you’re screwed. Finally, a fixed pump will only drain from one point in the hull.

It seems to me that the best solution is a petrol driven water pump or similar. Those can shift serious amounts of water a long way up hill, they will run for days, they can be moved to where you need them and they are independent of the boat’s electrical systems. You can buy a Honda that will shift 66000 lph for about 800 euro.

So why not have a manual pump, a rainwater electrical one on a float, and then a petrol beast for when TSHTF?

There are a couple of practicality issues with a gas powered pump. The biggest one is storing it safely and making sure it'll actually run when you need it. But it's also not automatic and has a few minutes of setup time. So it's basically a pump of last resort (for a serious hull breach, etc.).

Even if something like that is available, I'd want significant electrical pumping capacity that's automatically triggered. That way there's already significant water being moved by the time the high water alarm goes off, giving a better shot of sorting things out before the water gets high enough to knock out batteries, etc.

I'd also prefer a big belt drive pump (with a clutch) on the engine over a separate gas powered pump. Much quicker to get something like that started and running (no hoses to run, etc.) allowing you to start damage control sooner (assuming a small crew).

[Na Mara]

Hi rslifkin

I agree with you about the importance of prompt deployment of whatever system. That’s why a bilge alarm is a must. I would have it set to go off just above the float for the standard electrical pump.

Indeed the purpose of such a pump is to save the boat in case of a serious hull breach, the other pumps deal with everything else.

An engine driven pump is also a good idea but there are six problems with such systems. 1. They only pump from one location, 2, they require the electrical system to still be operable to get the engine started 3, they require a clutch that either is electric and so also requires a functioning electrical system or is manual and so requires getting up close and personal with the engine in an emergency, 4 they run only as long as the engine does and if the fuel pump is electric like mine then again when the electrical system fails, the pump fails, 5, they require an additional through hull, and finally 6 they aren’t cheap or easy to install.

For these reasons they are inferior to the standalone pumps.

That said you can also rig them for a deck wash and as the are made of bronze they will last longer than the standalone ones.

I agree it’s a better solution than an electric as a pump of last resort but not as good as a stand alone pump for me.

[DeValency]

While technically very true, practically, may not be a solution for most of us. Petrol pumps are bulky, heavy and require maintenance, safe storage out of the cabins etc. and still assure an immediate operation at emergency. The Coast Guard are known to deliver such pumps at emergencies, but these are used and well maintained all the time.

If there is one good reason to upgrade batteries to LFP, is the ability (and better practice) to install in elevated compartments and the ability to discharge higher currents to drive higher capacity portable emergency pumps. And you are benefiting from a bigger energy bank for all other uses, every day.

[Na Mara]

Most people can find space for a gas powered portable generator and a small petrol driven pump isn’t much bigger and has similar storage issues.

For example, there is a Honda capable of shifting 72 gpm that has dimensions (LWH) 14.0"x10.8"x14.8" and weighs 20lb. If 72gal per min is not enough then just carry two of them.

[capt jgw]

Originally Posted by Na Mara

I’ve often wondered at the wisdom of electrical bilge pumps run off the ships supply for dealing with hull breaches. Firstly, even the best of them won’t keep up with much more than a fitting leak. Secondly, the batteries on most boats are located low down for weight distribution which makes them vulnerable to flooding. When the electrical system fails you’re screwed. Finally, a fixed pump will only drain from one point in the hull.

It seems to me that the best solution is a petrol driven water pump or similar. Those can shift serious amounts of water a long way up hill, they will run for days, they can be moved to where you need them and they are independent of the boat’s electrical systems. You can buy a Honda that will shift 66000 lph for about 800 euro.

So why not have a manual pump, a rainwater electrical one on a float, and then a petrol beast for when TSHTF?

Here's my experience with gas powered rescue pumps: I was involved in a USCG rescue of a single handed sailor who was sinking. The CG rescue boat put a Machinist Mate aboard with a P5 dewatering pump. He couldn't get it started. Helicopter dropped him another one, no joy on that one either. Helo went back to base for a third pump, they finally got that one to run. Another five minutes and the boat would have been under, there was maybe a foot to go till the decks were awash.
Bilge pumps are like fire extinguishers. If you need them, no matter how many you have, it's not enough.

[AWT2_Sail]

Originally Posted by GordMay

IIRC, ABYC is silent on bilge pump capacity [GPH].
ABYC standards and recommended practices [‘H-22'] apply to all boats equipped with DC electric bilge pumps operating under 50 volts intended for control of spray, rainwater and normal accumulation of water due to seepage and spillage. This standard does not cover pumps intended for damage control.
Bilge Pump Rating - Bilge pumps shall be rated in gallons per hour versus heads at zero and three feet at design voltage. Positive or semi-positive displacement pumps shall also be rated at the maximum suction in feet at design voltage. Capacity and head may additionally be stated in SI units.

I sail corrected, sir. Thank you.
My surveyor was actually referencing a “general rule of thumb” rather than an ABYC standard. Seems reasonable, even though mine was set up so far away from that rule of thumb that I didn’t question it. Strange that they are silent on it.

[gwoiler]

Originally Posted by DeValency

Well, you are going to spend much more than $52 on a boat mainenence… and you don’t check water in the bilge by listening to your pump but by opening all the floor boards - ALL - including those normally not opened... Check the situation everywhere, trace any moisture, clean the bilge thoroughly and dry it until your Navy Ship Sergeant “can eat from the bilge”. Make sure also the pumps and sensors are perfectly clean. And then start checking how they function by controlled flooding of the bilge in multiple areas by hose and fresh water.
That’s in the first chapter of seamanship - in fact, has nothing to do with sailing or cruising… 🙂

I got another 2 hours at the boat today. Traced lines I was not sure about. In the main bilge is a milk crate full of all sorts of things. The WD40 was rusted at the bottom and leaking in the bilge. Another plastic bottle, about a quart, of hull cleaner, was leaking also. That stuff was nasty. Felt like brake fluid on my hands. Got rid of metal cans in that crate and left only the plastic. Bilge is clean now. Should stay clean also. It seems the bilge pump is in the engine room. It was not under the settee seating as some thought. Found all the water maker parts and cleaners under there. Looks like I have good room for 1 or 2 more pumps. When I was in bootcamp.... you had to clean the floor with a toothbrush if you did something wrong. Today, under the settee... I found all sorts of stuff from antifreeze, muriatic acid, - to motor oil... but is is all in French!

[Na Mara]

Any system can fail, but when you really need a serious bilge pump is when you can’t keep up with the inflow with your boat electric and manual pumps. I have been sailing nearly 40 years now and it’s has never happened to me. Indeed, I have never had a hull breach of any sort and I’ve hit rocks hard enough to send people flying in grp boats!

I see a gas pump as akin to a liferaft. It’s an insurance policy that requires regular service and maintenance. Just like the life raft it can fail when you need it most, but if you ensure the gas pump runs every time before you go further offshore than the coast guard and rescue services can easily get to then having one aboard will meaningfully increase your chances of survival if the worst happens. It doesn’t guarantee you and your boat make it home, but neither do the alternatives, all of which have far more failure modes and less capacity than a gas pump.

[GordMay]

Originally Posted by AWT2_Sail

I sail corrected, sir. Thank you.
Strange that they (ABYC) are silent on it (capacity).

Not really, since the Standard only applies to bilge pumps:
"... intended for control of spray, rainwater and normal accumulation of water due to seepage and spillage. This standard doesnot cover pumps intended for damage control ..."
which don't require very much capacity, at all.

[DeValency]

Originally Posted by gwoiler

I got another 2 hours at the boat today. Traced lines I was not sure about. In the main bilge is a milk crate full of all sorts of things. The WD40 was rusted at the bottom and leaking in the bilge. Another plastic bottle, about a quart, of hull cleaner, was leaking also. That stuff was nasty. Felt like brake fluid on my hands. Got rid of metal cans in that crate and left only the plastic. Bilge is clean now. Should stay clean also. It seems the bilge pump is in the engine room. It was not under the settee seating as some thought. Found all the water maker parts and cleaners under there. Looks like I have good room for 1 or 2 more pumps. When I was in bootcamp.... you had to clean the floor with a toothbrush if you did something wrong. Today, under the settee... I found all sorts of stuff from antifreeze, muriatic acid, - to motor oil... but is is all in French!

well, the deepest area in the bilge, where you want to look for water are not under the settees. Hopefully by now you have also found all your seacocks...

keep cleaning! This also helps in being familiar with your boat.

[gwoiler]

Originally Posted by DeValency

well, the deepest area in the bilge, where you want to look for water are not under the settees.

Of course it is not under the settee... Other Beneteau owners told me the PUMP was there.... but was not. Thanks just the same, though.

[GordMay]

Originally Posted by gwoiler

Of course it is not under the settee... Other Beneteau owners told me the PUMP was there.... but was not. Thanks just the same, though.

Diaphragm type bilge pumps are often located under a settee.
Because they are self-priming, you can pump your bilge almost completely dry with a diaphragm pump. This is usually impossible with a centrifugal pump, without installing a check valve, which can restrict the flow rate significantly, or [worse yet] fail closed. Also, you can install diaphragm pumps high above the bilge, reducing the chance of any stray DC current in the bilges.
I recommend both: with the diaphragm pump as your lowest mounted pump; and a centrifugal pump switch installed slightly higher.

[gwoiler]

Yes. Each time I have been able to visit my boat, I learn something new while attacking a specific project. The first project was devising a 12 volt dehumidifier. Done. CLean the bilge - Done. I have replaced the scupper cockpit drain hoses because they were leaking rain in to the boat - causing high humidity - fixed. Although I can hear the diaphragm bilge pump in the engine room, I have not yet set my eyes on it, because it will come. Next... to decide what to buy for a second pump.

[gwoiler]

OK. Installed a new float switch from Amazon. It looks like a RULE. It failed in the first week - stuck... ON. Visited the boat today and I could hear a noise. Sure enough - it was the bilge pump. Opened the bilge and the float was at the level in an almost dry bilge. I slightly touched the float,and the float dropped and pump shut off. Been reading the reviews on all the bilge switches and all have a small percentage of stuck "on" units. Some fail in a week or a few months to half a year. Is there a decent bilge float switch out there?!!!!


PS, the bilge pump was located on a wall in the engine room.