Auto Bilge Pump - How you connected ?

B27

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These days, with so many boats have a solar panel or two, 'battery isolators' don't always actually isolate the battery anyway.

I have an auto bilge pump connected to the small secondary fuse box which also serves the solar panels.
I'm conscious of the need to avoid pollution, so the float switch is set to only come on with a serious amount of water in the boat.

TBH, the electric bilge pump is pretty only there because it was a vague recommendation in the survey when I bought the boat and my insurance states all the recommendations have been followed.

I have some history with leaky old wooden boats where bilge pumps matter, even a small electric pump is equivalent to fairly tedious pumping.
 

Tranona

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I have to ask why?
If you need the protection of a bilge pump to deal with leaks when you are not there it must obviously be live all the time. If you don't want it to work when you are not there and power switched off then no need. as others have pointed out there is very little need for an automatic pump on a modern GRP boat - I did not have one on either of my Bavarias but if you have boat that leaks then the automatic pump should be live.
 

IanCC

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Just interested on peoples thoughts for this .... I have seen about equal split as to how connected.

Some have wired auto so it works when boat is left and main battery power is off.

Others I know have it only useable when main battery power is on.

All of course have dedicated switch to isolate the pump itself ... usually a 3 position : Manual - Off - Auto.
Fwiw.
Residual water in my bilge flattens battery as float switch keeps being activated as boat rocks, either at anchor or underway. I now have two switches one above the other. The upper switches it on and the lower switches it off.
 

NormanS

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When in the past, I used to have old wooden open boats, they didn't have any electrics, so when an automatic bilge pump would have been useful, I didn't have one.
More recently, for the past 45 years or so, I've had boats that don't leak, so see no need for an automatic pump.
I think that the less that is said about automatic bilge pumps, the better. You probably don't want a government directive insisting that every boat thus equipped, is required to have an anti-pollution boom around it. 🙁
 
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Refueler

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It is a total myth that a leak big enough to sink the boat cannot be dealt with by a bilge pump.

Depends on size of the hole !

But majority of leaks even on old boats can be handled by reasonable pump.

My Saaremaa Race boat was pine on elm carvel ... and she would have gaps up to 0.5 - 1mm in places when dried out over winter. Placed back in water - she needed to stay in slings for at least a couple of hours for strakes to take up ... a good mains powered pump placed in cabin to pump out the inflow.
There would be no possibility of the usual bilge pump coping with that ...

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FNrG5Lel.jpg


Suggestions of re-caulking to seal would have led to the strakes 'popping' the fastenings and serious damage to hull. First time lift in - nerves on edge .. but once done - all was fine.
She would be good after about 4 hours with only slight amount seeping in ... after a couple of days - she was dry and no leaks.
 

Porthandbuoy

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Auto/Off/Manual switch connected to the Always On bus. Physically smaller, lower capacity electric pump in deepest part of the bilge where the big mother doesn't fit; manual switch to domestic bank. Manual pump as well.
 

PaulRainbow

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If the pump is always on and it's a giant leak the batteries will likely go flat, then the boat will sink. It would have sunk anyway and a set of batteries is the least of your worries. No downside to leaving it on auto then.

If it's a tiny leak it should be OK, auto pump or not. Not likely to flatten the batteries, if does does, it isn't a tiny leak or you've got shit batteries. Again, no downside to leaving it on auto.

Then there's a host of other possible leaks that may or may not sink the boat with or without an auto pump, but i can't see a downside to leaving it on, i can see an obvious downside to not having it on, the boat sinks, or takes on enough water to do damage.

Pumping oil into the sea is a piss poor excuse for not having an auto pump, fix the oil leak !!

A few years ago my wife and I returned to the boat after an evening at the sailing club and sat down with a glass of something or another. I could hear water dripping and check all of the taps, nothing dripping there. I lifted a sole board and the bilges were full right up underneath the sole boards ! Why hadn't the auto pump dealt with it ? The switch panel was in the walkway to the aft cabin and it had been knocked to the off position. I turned it to auto and it cleared the water after a time. Investigations revealed that the changeover valve for the holding tank had allowed sea water back into the holding tank and the holding tank vent was broken. It was not a big leak, the auto pump and batteries would have coped (was on shore power anyway), but had we have been away for a few days the boat could have sunk.
 

onesea

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No downside to leaving it on auto then.....

It was not a big leak, the auto pump and batteries would have coped (was on shore power anyway),.....

Now a little bit of devil's advocate...

With leaving the pump off, I always leave the seacocks closed when I leave the boat for any period of time (ie not sleeping in board).

The advantages are if the boat gets a small leak I will notice when the bilge pump runs as I put the breaker in.

I have found many a deck leak due to finding water in the bilge. Had the pump been on auto I may not known about the leak to find it's source.

One a deck fitting that looked secure. Water running behind panelling into engine compartment. It was only when looking for the leak on a wet day did I put my hand behind the frame and find the moisture.

Had the pump been on auto I would never of known about the leak.

I have to agree now with solar, there is less reason to turn the pump off.

However for most modern boats I question if it's necessary to leave it on.

Unless it has a counting device it may let small leaks develop into big leaks unnoticed.
 

jwilson

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It is a total myth that a leak big enough to sink the boat cannot be dealt with by a bilge pump.
I regret to say I once attended a sinking boat (not mine) where the auto bilge pump had already flattened the batteries. It finished sinking before anyone could get a petrol fire pump on board.
 

Refueler

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"onesea" .... does your bilge pump remove A:LL water ? If it does - can you please tell me the brand / model ?

All bilge pumps I have seen / used / have - all leave a small amount unpumpable ... reason for my comment before that if you have mopped out the bilge - if you then find a small amount even with pump on auto - you know you have a leak.

"I have found many a deck leak due to finding water in the bilge. Had the pump been on auto I may not known about the leak to find it's source.

One a deck fitting that looked secure. Water running behind panelling into engine compartment. It was only when looking for the leak on a wet day did I put my hand behind the frame and find the moisture."


Sorry but I think you would have found that regardless of pump auto or not ...

As to boats leaking ? I would suggest that very few boats are fully dry ... even condensation can accumulate and depending on climate / location - a surprising amount can collect.
 

onesea

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"onesea" .... does your bilge pump remove A:LL water ? If it does - can you please tell me the brand / model ?

It leaves very little in the bilge more by accident than design. I cannot sound it out to find out how much is left. Less than an inch in a wet dry hoover?

The pump is placed (Wedged literally) just aft of the fiberglass encapsulated ballast at the bottom of a long keel. The gap is just wide enough for the pump (bought with tape measure in hand).
The echo sounder transducer is just aft of it as they cannot fit side by side.

I will not access the pump without a 2nd person present for fear of getting stuck probably by my head as there is little space down there.

The area is also known as the pit of dispare. We have countless tools of revival grabbers magnets etc. Once in a while we find 240v and it gets wet and dry vacuumed. Normally to recover stuff dropped.

No she is not totally dry, no boat ever is I agree.

Presently it's coming in from toe rail in stern locker (removing/ replacing this is ear marked as next project).

She is left well ventilated so condensation is minimal when we are not on board.

My last boat had a round flat bilge, an electric pump would leave several buckets of water in the bilge. I sponged her out regularly, the keel stepped mast let in water.
In the end I blocked the lumber holes for the section under and the mast, the rest of the bilges stayed dry. Or I started looking for the leak.

Even a cm of water on that flat bilge would have a massive surface area to and the damp would start all over the boat.
 

PaulRainbow

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Now a little bit of devil's advocate...

With leaving the pump off, I always leave the seacocks closed when I leave the boat for any period of time (ie not sleeping in board).

The advantages are if the boat gets a small leak I will notice when the bilge pump runs as I put the breaker in.

I have found many a deck leak due to finding water in the bilge. Had the pump been on auto I may not known about the leak to find it's source.

One a deck fitting that looked secure. Water running behind panelling into engine compartment. It was only when looking for the leak on a wet day did I put my hand behind the frame and find the moisture.

Had the pump been on auto I would never of known about the leak.

I have to agree now with solar, there is less reason to turn the pump off.

However for most modern boats I question if it's necessary to leave it on.

Unless it has a counting device it may let small leaks develop into big leaks unnoticed.
We bought our present boat two years ago. A little tired and in need of a bit of a refit. Amongst the list of jobs was a new float switch in the engine room (boat has three electric pumps in separate "compartments", each sealed up to a point). Coming back to the boat one day i thought she looked a bit low in the water. Looking around i opened the hatch to the engine room, to find about a foot of water in there, just up to the engine sumps. Turned out to be a leaking stern gland, a fast drip, bordering on a slow dribble. No sea cocks on the stern glands. Needless to say, the float switch was replaced pronto.
 

oldmanofthehills

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I have main auto pump on permanent on aux battery plus a sendary auto pump half way up the pump well on its own battery. Need 3 way charging from alternater via diode or just a manual switch if emergency battery flat.

You would be amazed how many boats sink on moorings. Mine did due to chain tangle in stormy weather and pump would have done nothing but insurance assessor stated that boats rarely sink at sea but are unattended for many many more hours on mooring and sink there instead

Some craft are really sad to see coming to such an end, other a complete pain to harbourmaster or club
 

wingcommander

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Auto bilge pump wired directly to input of service battery switch (so always live) . Inline fuse . Pump located in a very inaccessible void under engine aft of long encapsulated keel . So pump is attached to a 3ft long PVC strip ,which is lower an then secured away from prop / gearbox flange. Can't actually see were the pump is located, however if could go any lower it would be external, and running continuously
 

Refueler

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My Primor MoBo - today I find out has water leak into engine bay ... being typical boat - trying to see all around the bay .. engine and outdrive area is contortionists nightmare ...

Think the wandering scope is going to have to come out of its box.

Its also a real pain lifting the huge cockpit floor section to get at the bay ..

Looks like I need to plan a day to remove all seats ... canopy ... floor sections .... then dry out .. sprinkle talcum powder around and see where its trickling in ..
 
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