Should Bilge pump be wired directly to battery?

Having seen a modern boat suffer a very simple failure, through no fault of the builder, I would agree that an automatic bilge pump wired via a fuse and switch to a battery is a wise idea. It doesn't take long for a little leak to top up a boat. A solar panel and simple controller on the same battery is a good improvement and some of the cheapest controllers even have an outlet that is fed from the battery and will continue to power whatever it supplies until the battery voltage falls to the point of causing it damage and then switches it off until the battery is restored to an acceptable level.

Yoda
 
No, the worst case scenario is that the float switch jams (as they are prone to do), the pump runs continuously without water, it overheats, catches fire ...

In my view the bilge pump should be switched off with everything else when leaving the boat.

Most bilge pumps are designed to run dry without damage.

If,as you say,the bilge pump won't cope with any significant ingress of water,why waste money having one?:confused: Yet you say you do---but leave it switched off when the boat is at it's most vulnerable.
You need to study logic!
 
The answer is yes it should be wired to your domestic battery, mine is from the main fused panel via a permanently live (fused) connection, I then leave it switched to auto, I have a whale pump with the sensor rather than a mechanical switch as I feel this is more reliable and unlickley to switch permanently on and allow the pump to run dry.
 
No, the worst case scenario is that the float switch jams (as they are prone to do), the pump runs continuously without water, it overheats, catches fire ...

In my view the bilge pump should be switched off with everything else when leaving the boat.

Risking this then, surely better to leave it on but suitably fused!
 
No, the worst case scenario is that the float switch jams (as they are prone to do), the pump runs continuously without water, it overheats, catches fire ...

In my view the bilge pump should be switched off with everything else when leaving the boat.

I use a Whale Supersub 650 which does not 'Jam' as it has a sensitive head that activates when water over 3" deep covers it, (I also check and clean it every three months).

Nothing electrically is 'alive' when I leave the boat, as the pump via the bilge control switch (left in auto) and an 'in line fuse' is direct to the domestic battery 'nothing else', so the pump only activates when it is covered by water.

To leave a boat with no automatic bilge pump in my opinion is just is an accident waiting to happen.
 
Well i've just fitted a new pump, which is wired via the float to the battery, but i also have it wired through a switched supply, so i can pump that little extra out if needed.
Regardless of whether your boat is watertight or not,it dose'nt take much to cause a leak, i fitted a new rudder pin on my last boat, and the screw went slightly too far through the hull, and although it did not 'break through' the other side it caused a leak, so much that within a couple of weeks it had flooded the rear locker my 1 ft.
My new boat is leaking from the cockpit, so a pump is important until i track down the leak.
 
Why do you need a permanent bilge pump in a modern yacht?
Because modern yachts are built to RCD which state that 'seacocks must be good for at least 5 years'. This invariably means that most manufacturer's fit BRASS!!
So if you don't change you seacocks and replace with either Marelon or Bronze, within 5 years you risk losing your boat.

There is a case in our marina of a Hanse that was only 4 and half years old before the seacock failed.
 
No, the most elegant solution is a watertight boat which does not need the bilge pumped while on its mooring. I've been well involved with wooden boats where this is not going to be the case, but it should be the case for most GRP boats.
You will find several people on these forums who have had quantities of fuel or oil getting into the bilge. Having that automatically pumped overboard could lead to a very big fine these days.
I'm also not sure what failure a little Rule pump is going to save the average JenBenBavSterly from. Most of things that go through the hull will leak a lot faster than those things can pump, and most yachts don't have the battery capacity anyway.
Surely "watertight boat" is an oxymoron.

Few boats leak from below the waterline, but nearly all boats, subjected to a sufficiently heavy downpour, will leak through hatches, glands etc.
 
Because modern yachts are built to RCD which state that 'seacocks must be good for at least 5 years'. This invariably means that most manufacturer's fit BRASS!!
So if you don't change you seacocks and replace with either Marelon or Bronze, within 5 years you risk losing your boat.

There is a case in our marina of a Hanse that was only 4 and half years old before the seacock failed.

I think anyone who expects a small pump running off a 12V battery to cope with the results of a failing seacock or skin fitting is sadly misguided.
 
Because modern yachts are built to RCD which state that 'seacocks must be good for at least 5 years'. This invariably means that most manufacturer's fit BRASS!!
So if you don't change you seacocks and replace with either Marelon or Bronze, within 5 years you risk losing your boat.

And how exactly is the normal 20-litres-per-minute-if-you're-lucky centrifugal bilge pump going to help with that?

A quick google suggests that the inflow rate from a hole 1m below the surface is about 330 l/m.

Pete
 
Two bilge pumps with air operated level switches set at different levels connected through circuit breakers direct to domestic batteries and electro mechanical counters to indicate how often the pumps operate.

Battery also kept topped up by solar panels but not enough to keep pump running all the time.
 
I think anyone who expects a small pump running off a 12V battery to cope with the results of a failing seacock or skin fitting is sadly misguided.
Seacocks usually LEAK before they fail.
Most boat owners, when seeing a bilge pump discharging frequently would usually inform the owner or marina office.
Fitting a small bilge pump is next to useless.
Anyway, personal choice, why bother fitting bilge pumps at all if they can't cope ?
 
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And how exactly is the normal 20-litres-per-minute-if-you're-lucky centrifugal bilge pump going to help with that?

A quick google suggests that the inflow rate from a hole 1m below the surface is about 330 l/m.

Pete

See my last reply to OP
 
Logic

So a fitted pump is useless if the sea cock fails, But what about if the hatch is accidentally left open, or someone kicks in the washboards?
Or maybe the self draining cockpit get blocked up and does not self drain?
Any number of things could happen bearing in mind our boats are usually moored in the very rainy UK, and is sat in guess what ? Water!
 
No, the most elegant solution is a watertight boat which does not need the bilge pumped while on its mooring. I've been well involved with wooden boats where this is not going to be the case, but it should be the case for most GRP boats.
You will find several people on these forums who have had quantities of fuel or oil getting into the bilge. Having that automatically pumped overboard could lead to a very big fine these days.
I'm also not sure what failure a little Rule pump is going to save the average JenBenBavSterly from. Most of things that go through the hull will leak a lot faster than those things can pump, and most yachts don't have the battery capacity anyway.

Well some of us have a packed gland which can leak and even those with mechanical seals can have a catastrophic effect when the seal fails .

I use an oil filter on the bilge pump out let to avoid any environmental issues
 
I've never left my boat on a mooring for a month without looking at it.
People who leave the hatches open will probably leave the lights on too, where is your elctric pump then?

I can see that a bilge pump is going to help if your boat leaks a certain amount of rain. One boat I sailed on, the mast drained into the shower, the shower sump pump was left on auto via its own fuse.

Some MAB owners seem much happier to fit auto bilge pumps than to keep the rain out. Are they addicted to the smell of mildew?

The front lockers on my catamaran have a drain with a NRV on the outlet Its one of those NRV's that has a piston like flap . This filled up with debris and locked it shut and rainwater flow into them was sufficient to tilt the boat with its bum in the air . Marina had to break in to pump out .
While I was grateful for their attention I now inform them that there are two manual bilge pumps accessible in the cock pit for future use .

I have removed the NRV which was to prevent seawater entry when the boat pitched in heavy weather
 
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