How many bilge pumps?

[TrentePieds]

gwoiler said: "Not sure if you can see it, but there are wire splices below the water. I don't like that."

In my previous post I mumbled something about "other issues" and about a 4K gph pump being overkill. Those mumblings were precisely in anticipation of what you've now shown us.

I want to start by saying something that will get me accused of being a Luddite. I plead guilty. Nevertheless, think about this: As MicHugh points out, you boat doesn't really have a bilge as such. That's why there is what he calls a "shoebox" otherwise known as a "suction well". But there is no reason that you should EVER get more water in the bilge than the shoebox can hold! If you do there are things other than the pump you'll need to address :-)! We can come back to that.

I can't tell from your pics what the dimensions of the shoebox are, but it will certainly hold the little beauty below. It measures 6 1/2" x 5" x 4" and is said to shift 1,100 gph! And the float switch is built in. And it'll set you back maybe forty bux, so it's a "throw way" if is wipes out. And a plug'n'play to replace :-)

Now, if your shoebox is, say, 8"x 4" x4" = 128 CuIn, it will hold less than half a gallon of water, which probably isn't altogether wrong. But you can do these numbers yourself. There are 277 CuIn to a gallon.

And now it's time to knock a misconception on the head: Bilge pumps are NOT meant to be "de-watering" pumps. They are NOT meant to save your boat and your butt if you punch a hole in the hull! It's up to you as the skipper to make sure that that NEVER happens.

Bilge pumps are just for keeping tidy :-)

Flow rates are constrained by the dimensions of the exhaust hoses and the entry/exit pressure differential in the system, and not (at least almost never) by the pump capacity, and that is why I said that 4K gph is overkill.

You already know, since you are on 12V off-grid in your cabin, how to do a SOLDER joint in wire and how to make it water tight. You know how to use terminal blocks. So fixing you bilge pump setup will be a walk in the park. Provided you rip all the garbage out BEFORE you even start with the new stuff.

There are lotsa ways of doing it, but what you've got obviously isn't one of them :-)

Have fun improving you boat :-)!

TrentePieds

[Marathon1150]

Originally Posted by MicHughV

That little strainer will clog in an instant.

From personal experience on two occasions, I can confirm this to be absolutely correct. Fortunately the manual bilge pump (Plastimo) moves quite a lot of water.

I now make a point of hosing out the entire bilge area from port side to starboard side several times a year.

Dogs that shed are also a problem. I had the Jabsco rebuilt when I could not get it to pump water from the bilge and was informed by the shop doing the work that the pump was fine. The problem was a ball of fine dog hair (Nova Scotia Duck Toller inner coat) jammed just before the inlet into the filter housing noted above.

[rslifkin]

Originally Posted by TrentePieds

And now it's time to knock a misconception on the head: Bilge pumps are NOT meant to be "de-watering" pumps. They are NOT meant to save your boat and your butt if you punch a hole in the hull! It's up to you as the skipper to make sure that that NEVER happens.

No reasonable bilge pump setup will keep up with a hull breach. But keeping up with a failed thru hull is very possible. Basically, the more water you can move in an emergency, the longer you have to find the problem and do something about it before there's too much water to see or access the problem. And bigger pumps will get the water out faster after the inflow is mitigated.

On a typical small boat, I don't count manual pumps as usable pumping capacity during an emergency, only for dewatering after. Most of us don't have a large crew on board, so it's not guaranteed to have an extra person to operate a manual pump, as they're likely to be assisting with finding and resolving the problem (or manning the helm).

[gwoiler]

Originally Posted by MicHughV

I don't think there is a logical solution to the bilge/bilge pump problem on the Bennie 423. Overall, I love the boat, it's a sweet sailor, but the bilge could use a re-think.

Yes. The 40cc is also sweet, but nothing is perfect. I am thinking to install 2 more pumps besides the original.... or at least 1, and a spare tucked away. The previous owner told me at one time he had installed a small pump up next to the base of the mast. He took it out, saying he never used it. I did find a 1/2 inch hose up there with a clamp all by itself. I also found an inch of fresh water in that bilge, and scooped it out. Have not yet taken a look at the mast thru the deck.

[MicHughV]

Water inside a boat can come from unusual sources.

I had an instance where the rubber exhaust hose came off the fiberglass riser...how...why....I do not know....that connection had two stainless steel hose clamps, but maybe they were not true stainless steel. With the engine running....at night off course....these things always happen at night....raw seawater was just pumping inside the boat, instead of going out the exhaust. I had noticed a stream of water coming out of the bilge pump overboard hull fitting, but it stopped, and I thought that was that. Not long after, my crew went down the companionway and noted water over the cabin sole. The bilge pump had obviously clogged up and quit working.

Let me tell you, nothing quite gets the attention of a sailor as water over the floorboards....at night to boot....
It was a frantic time using the cockpit mounted hand pump and a bucket. Once we had the level of the water down a bit, I did a frantic search of thru' hulls but could find no issue there. The engine was kept running, although we had stopped the boat. At this time, I decided to look inside the engine compartment, thinking stuffing box problems but saw right away the source of the problem. I made some makeshift repairs to stop the leak until morning arrived and I was better able to address a fix.

Nonetheless, it was a terrifying experience and I have since become paranoid about checking the bilge visually every 30 minutes or so while underway.

At another time, I was in some really terrible weather. The boat was sealed up tight, and myself and crew were lashed inside the cockpit. Seas were breaking over the entire boat, and unbeknownst to us, was coming inside the boat from the little drainage holes on the side of the dorade box vents. Yep, those little dime sized holes. When we finally dared open the companionway again, the inside of my boat was a veritable swimming pool. Everything I owned was soaked. It took the best part of 12 hours of labor to get some semblance of normalcy again.

Isn't sailing fun....

[gwoiler]

Originally Posted by MicHughV

Water inside a boat can come from unusual sources. Isn't sailing fun....

Thanks for the stories. I am close to start living my own stories. Since living off grid in a small home on 20 acres from 1998 until today, I have rebuilt chinese diesel generators, trouble shoot everything that can go wrong with solar systems and big batteries, and water systems... not to mention the 1938 road grader, tractor, spring and gravity flow water system... and on and on. Winters with more snow than time to plow... and all the break downs in a blizzard! But the common key is, you fix the problems and keep fixing them as they happen. Hopefully, good methods are used so there is longevity in the repaired systems. Even when teaching myself to fly an Ultralite, things went wrong. You can not say pause. You stick with it. So now... another arena with challenges. What do they say? The best defense is a good offense? I agree. Good maintenance, common sense, and a prayer go a long way!

[Startracker]

Originally Posted by gwoiler

Thanks for the stories. I am close to start living my own stories. Since living off grid in a small home on 20 acres from 1998 until today, I have rebuilt chinese diesel generators, trouble shoot everything that can go wrong with solar systems and big batteries, and water systems... not to mention the 1938 road grader, tractor, spring and gravity flow water system... and on and on. Winters with more snow than time to plow... and all the break downs in a blizzard! But the common key is, you fix the problems and keep fixing them as they happen. Hopefully, good methods are used so there is longevity in the repaired systems. Even when teaching myself to fly an Ultralite, things went wrong. You can not say pause. You stick with it. So now... another arena with challenges. What do they say? The best defense is a good offense? I agree. Good maintenance, common sense, and a prayer go a long way!

For what it's worth you'll likely be well suited to solving this sort of thing then.
For what it's worth, I wouldn't solder anything involved in this, but would use good quality heat shrink connectors. Maine Sail's article a while ago put me onto FTZ connectors. The Clearseal are far, far superior to the junk that is sold today under many reputable brands with issues like ring terminals with heat shrink overlapping onto the ring so each must be cleaned with a knife.

While it is true that pumps are generally for nuisance water, not de-watering. I had an ancient homesite little trash pump I think I paid 50$ for it. That damn thing was so useful. In order to make sure I was keeping it moving, I made a habit of using it to wash the decks then spraying the inside of the pump with whatever anti-corrosion spray was handy. It didn't take up much room, depending on nothing else in the boat, having it's own gas motor and was quite happy to suck up damn near anything. It was utterly reliable, and the previous owner had used it for 30 years that he could remember, everything from sucking up mud sand and filth to a septic system. Even in a worst case scenario, a couple pulls, prime it at water level, once it's sucking then drop it on deck and it will pump until the decks are underwater. A boat neighbour used it to de-water a sinking boat, seemed to do the trick.
https://www.homedepot.ca/product/gen...E&gclsrc=aw.ds
Is a smaller modern version that'll do 1800 GPH.

A larger cousin of the pump was also used to dig out a boat that was on the beach, hand digging was impossible, but I'd seen an old black and white photo of miners using high pressure water a hundred years ago and it came to mind at the time and worked!

I find float switches these days are not to be trusted. The trick is to find an old one, they used to use mercury switches. I had a stash of them I gave away before realizing I couldn't find any more. The mercury switches work brilliantly and never seem to fail like the new ones.

The second thing I trust even less is switches on a panel. While the owner is often good about it, guests are not! Off is often where the switch will naturally sit to the eye of a guest. Personally, and this is only personally, I hardwire at least one pump, the scavenger direct to the battery with no switches allowed. The mid pump gets the on/off/automatic switch, and the emergency pump is manual only.

For my new to me boat, I will be upgrading as follows:
Either 1 of Rule 500 automatic pump, the style that cycles the pump every so often, and looks for shaft load before deciding to pump. I dislike rule pumps immensely, Johnson with the quick change motor are much much easier to service, but the lack of a float switch, or electrical switch which may have issues in contaminated water is perfect for this use.
Or my preferred pump which still relies on a switch, the Johnson 750, the motor is swappable with a quarter turn no tools, so spares are easy to carry and swap. I like the pump better, but have seen the rule automatic load system be utterly reliable so I'm undecided as of yet.
This will be my "scavenging" pump, the one that takes on all the wear and tear and day to day use/dirt etc. Directly wired to the house battery. The reason being the house battery is usually much larger, but with some risk of it being drained at the time of need. I may end up with both, with the rule at the bottom. Indicator light for the rule automatic or cycle counter on the Johnson scavenger pump only.

just under deck level a Johnson 2200 Heavy Duty bilge pump, manually switched, wired off the Start batteries, automatic switched as well only if I don't install the mid pump. In a failure underway I can turn on the engine to keep the batteries up, but it won't leave me with dead batteries from an automatic switch. Not so easy to service as the 500s, but much much tougher. Hopefully this pump is never used. If it is I know it is in like new condition. In my opinion scavenger pumps should be regarded as likely to fail at any time, and putting all that wear on a cheap pump gives me peace of mind.

Note however that I have a single narrow 3 foot deep midsection in my bilge, every other space naturally drains there, with shallow bilges that layout may be different, or with watertight bulkheads pumps in various areas may be needed. On boats with a separate compartment I quite like a dedicated pump at the shaft, exiting the opposite side of the boat. That way I know if that pump is kicked in, I have a failure in the engine compartment, the most likely place I've seen for leaks.

I also have a manual gulper pump already at the helm.


https://www.efunda.com/formulae/flui..._tank.cfm#calc
This is a neat tool for getting an idea of how much water a failure will let in. I set it at 2' deep as that's the depth of most of my hull penetrations, 1.5" hole and ask for results in GPM.
While not exact, it does indicate I would be looking at about 61GPM, or 3660 GPH. This tells me that losing either a single 1-1/2" thru hull entirely, or a catastrophic driveshaft seal failure, including those 3 electric pumps only, and I will be taking on approx 1000GPH (2200+750+500)X0.75 to account for height of discharge fittings =2587.5 GPH discharge. A 1-1/2" thru hul about 490 cubic feet of water an hour, of which approximately 71% will go back overboard, leaving me with a net intake of 142 cubic feet of water an hour. A very very rough estimate of my interior volume at 2' above the bottom of the main bilge gives me 540 Cubic feet of volume. At this height the batteries will be underwater so no more pumping, and another few inches and the motor will ingest water if still running. And here I told my teachers I'd never use math for fun in life. This tells me that I will have about 4 hours with pumps running, or about one hour with no pumps to the point at which abandoning ship is likely. 4 hours is enough for me to fix anything that can be fixed. If I can't get a plug in the hole in that time, a tarp or something on the outside, I won't be able to do it. 4 hours in most places I'll be is enough to get to land as well, and certainly a good chance of SAR being on scene. One hour isn't enough time in my opinion.
This also tells me that with the trash pump running on deck, I will have a reserve capacity of 727 Gallons per hour, so even with the loss of a thru hull or shaft seal, and no ability to repair, I can stay afloat as long as the fuel lasts.

If you're ever bored and want to get an idea of what this is like, many transducers are removable from their thru-hull inside. I pulled mine a few times to practice plugging them with wood and foam plugs while not stressed. In the end I liked the foam better. I did this on the hard first before practicing in the water, and I had my trash pump already rigged in case something went awry.

[moseriw]

Marathon1150 I think that I might also agree that the electronic sensors are better than float switches. We have both and the electronic version (two small metal pins which when immersed in seawater complete a circuit) seems to be more responsive to water in the bilge.

Can you please post some details. Mr. google denies results. Thank YOU.

[gwoiler]

Originally Posted by Startracker

For what it's worth you'll likely be well suited to solving this sort of thing then.
While it is true that pumps are generally for nuisance water, not de-watering. I had an ancient homesite little trash pump I think I paid 50$ for it. That damn thing was so useful. In order to make sure I was keeping it moving, I made a habit of using it to wash the decks then spraying the inside of the pump with whatever anti-corrosion spray was handy. It didn't take up much room, depending on nothing else in the boat, having it's own gas motor and was quite happy to suck up damn near anything. It was utterly reliable, and the previous owner had used it for 30 years that he could remember, everything from sucking up mud sand and filth to a septic system. Even in a worst case scenario, a couple pulls, prime it at water level, once it's sucking then drop it on deck and it will pump until the decks are underwater. A boat neighbour used it to de-water a sinking boat, seemed to do the trick.

The Trash Pump is a great idea. I have often wondered if this option was viable. It always seemed to me that a small portable gas driven pump could be a huge asset in trouble. I did not know though, if there would be room to store it and hoses. Thanks for taking the time to write all that up. So.... No one makes a mercury float switch any longer?

[moseriw]

OH NO not the terrible bad mercury! One can use swim switches from swiming pools. They have a metal ball inside but unfortunately they are not really reliable. The problem is that you shall mount it aground and wait until it is afloat vertically until the ball falls. When it comes back to horizontal the ball still sticks on the contacts and it is a question of luck if the swimmer goes down as much to ensure proper working and not sticking on the variable "wave height" These units are usually 4-5'' long.

btw. lots of fload switches (with an arm) use the same principle but they usually start when the arm is fully up and stop when the ball can roll downwards inside the arm.

So the way is mechanic and the question is if mercury is so much better than a metal ball inside.

[gwoiler]

What about the switches that are a small diameter hose/tube that senses the increased pressure as the water raises? The actual switch is higher up. No one has commented on them.

[MicHughV]

Some of the posters here bring up a good point...which is battery location.

Obviously, due to their weight, the ideal location is low and central, but too low also puts them within reach of water ingress.

Once water reaches the battery terminal's, you will have a problem.

Many boats have batteries connected together, so when one goes, they all go.

Battery location requires some serious thought.

[rslifkin]

Originally Posted by MicHughV

Some of the posters here bring up a good point...which is battery location.

Obviously, due to their weight, the ideal location is low and central, but too low also puts them within reach of water ingress.

Once water reaches the battery terminal's, you will have a problem.

Many boats have batteries connected together, so when one goes, they all go.

Battery location requires some serious thought.

That's a good point. The lower your batteries are, the more important really big pumps are (to hopefully let you find and slow the leak before flooding the batteries).



On my own boat, the batteries sit on a floor panel that bridges the keel sump. And they're L16s, so they're a bit over 16 inches tall. The keel sump on my boat (long keel powerboat) holds quite a bit of water. I figure by the time I flood the boat up to the top of the batteries, the engines are submerged about 1/3 of the way, transmissions are underwater, generator head is getting wet, and there's likely enough water in the boat that the situation is potentially unrecoverable.

[MicHughV]

While I'm at it.....I can relate one other problem I encountered.

I used the wrong kind of hose for a sink drain, when I was building my boat. I didn't have much money, so always opted for the least expensive item I could find. Big mistake !!

In this case, it was that cheap accordion type plastic hose...it drained the galley sink.

That night, I had guests onboard that were sleeping in the dinette area. The lady guest woke during the night (we were anchored) to use the bathroom, stepped on the floor only to find water covering her ankles.

It goes without saying, she woke me up.

Again, I had a bilge pump malfunction (bad wiring connection), but after using the manual pump to pump the water down, I set about to find the source of the leak. Off course, I checked all the thru' hulls, but no problem there.

I eventually traced the leak to a pinhole sized hole in the aforementioned accordion hose. It was a seriously small spurt of water, about what you'd expect coming from a syringe needle, but over a period of hours, it filled the boat to above the cabin sole.

Had I not been on the boat, it would have sunk.

It goes without saying, the hose was immediately replaced with the proper hose.

Looking back, I have escaped some serious sinking issues. Lessons learned the hard way.

I can only surmise that the good Lord looks after fools, drunks and sailors, so I'm well covered under all three descriptions.

[Startracker]

Originally Posted by gwoiler

The Trash Pump is a great idea. I have often wondered if this option was viable. It always seemed to me that a small portable gas driven pump could be a huge asset in trouble. I did not know though, if there would be room to store it and hoses. Thanks for taking the time to write all that up. So.... No one makes a mercury float switch any longer?

Useful more often than you'd think. And if you make a habit of washing your boat with it, you know it's in good order. I used to rent it for 40$ for the day along with bucket, high end deck brushes and scrubbers etc to other anchor outs. Good ROI on 50$. I used to loan it for free, but people abused that and I was always chasing people to get it back. at 40$ a day it came back sharpish.
Murphy is a jerk, the odds of more going wrong when taking on water are pretty good. I recall an incident report of a nicely equipped sailboat on route back to the USA for sale from what I remember, after years of cruising that started taking on water after being knocked down. Books etc ended up in the wrong place, and the paper mush plugged pumps if I remember right. Boat was a total loss without insurance. I like knowing my pump will ingest whatever is going on.


Sadly for us no, but they're bad for the environment. The nice thing about the mercury is it moved in a sealed tube, no corrosion, no fuss, no mess.
The ball type or electronic float switch type are pretty much crap.

RE: Air switches and direct electronic(sensing type) switches.
Both are great, if you can eat out of your bilge. The air ones are susceptible to plugging, had a customer who's boat filled up with a water witch. Cleaned the boat, cleaned the bilge it worked fine. He was leaking a ton of oil, my guess was that it somehow coated the sensors enough to stop it working but I'm not sure if that's the case. Both are good candidates for the mid/high pumps, but even regular old float switches are OK there.
ALL switch types IMO require regular testing as part of your routine service.
Except for the Rule ones that checks pump load, and there I just replace the pump on a schedule. The only problem I've ever had with these was a customer who's discharge line was just the wrong length. It would pump bilge dry, shut down, water flow back out of line raising the level enough that the pump would run at next check.

Also note, Attwood pumps and worst marine house brand pumps, and pretty much anything that isn't rule(ok) or Johnson(excellent). I installed a pile of them over a few months, when Worst Marine talked me into it. 50% I had to replace for free inside of 6 months.