What should I look for?

byron

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I went to start my boat today and the battery was as flat as a pancake. The Isolator had been turned off so that didn't drain it. The battery is brand spanking new and was fully charged.

Anyone suggest something simple or should I call in an auto-electrician?
 
I went to start my boat today and the battery was as flat as a pancake. The Isolator had been turned off so that didn't drain it. The battery is brand spanking new and was fully charged.

Anyone suggest something simple or should I call in an auto-electrician?

How old is 'brand spanking new' ? How was it fully charged and - not being facetious - are you sure?

I'd probably take it down to the local garage and ask them to put the tester on it for you.

Alternatively, can you put it on charge overnight and see what it's like in the morning?
 
It is possible it could have lost its charge if left for a while before using. If the isolator was turned off then there can`t be anything to drain it. It may just want a bit of a charge and some use. Happy to have a look at some point , I`ve got a "booster pack" starter so we could jump start it and see how it is after a run.
 
are there ANY electrical devices connected directly - e.g. security gadgets, gas detectors ? If there are any small wires going to the terminals or downstream of the principal busbars, check them with an ammeter when you have the batts charged again.
 
It is literally "NEW" last week. It is a top quality Tractor Battery from Walter Wilders and put in by one of their Engineers who had serviced my engine.

Although it wasn't given a top-up charge before fitting it has been on a 2 hour run so should be topped up. When I went to use it just 3 days later it was so flat it couldn't even make the ignition light glow.

There are, as far as I can see, no wires other than the lead that passes through the Isolating Switch.

I' leaving it on an overnight charge and will then see if it discharges itself again.
 
sometimes a battery left uncharged on a shelf for a while can need several charges and discharges to "wake up".

Do you have a SG tester ? If yes, what readings are you getting prior to, and after a good charge ? One duff cell will render a whole battery useless.
 
Faulty switch on an automatic bilge pump maybe ?

My launch is essentially the same as when Thames Water/Conservancy sold it off. It has no electric bilge pump just a manual one. I asked John Blake to put in an electric one about 3 years ago and I am still waiting. I guess it's just one of life's mysteries but if I ever resolve it I will post the answer.
 
Only 3 years!!

Oi. Get in line!!
This is why I change my boats every 3 years. Most parts can last that time without ministrations from John.

Now, all this talk of "SG" and other technical stuff ..........
Go and have a lie down, Byron.

How come you waved at Seaweed, 2 weekends ago and ignored me, although I could see you busy holding court with Thames Valley Cruising Club. I am only slightly offended!
 
Well if you are good at boaty mysteries i have one for you . My runabout has a very small leak aft and the water drains out near the bow . But it doesnt leak from the bow and wont drain out aft .
 
Non return valve Cuchilo? Could be a leaf or even a fag packet over a hole perhaps? As for the battery Byron, sounds very much like an internal fault giving either a dead cell or the equivalent to a dead cell. SG each cell, indeed if its just been fitted I'd think it reasonable for the engineer to come and have a shufti.
 
Mystery solved (I think). I just spoke to my pal who said that the other day he found the key was left in the ignition but not switched on however the Isolator key was in place and switched on. It was him who removed it.
So! I toddle down and everything seemed normal as everything was as it should be. Whereas the battery had been left switched on for a few days. Here's hoping :)
 
umm, that means there is something or things using up your battery power when the isolater is not in use. Sounds like quite a power drain if it flattens a battery in a couple of days.

Are you happy with an unknown device being switched on all the time, or do you just like nautical mysteries ? ;)
 
I suppose there must be something there draining things when the Isolator is on. The only thing I know of is the car radio taking milliamps for its memory. Obviously there must be something else too but as I normally faithfully throw that Isolator every time the boat is left I'm not too worried. Maybe when I get a visitor who is up on these things I will get them to test for me.
The launch has nothing else other than the car radio (which is never used). There's no VHF., Echo Sounder, electric bilge pump, GPS or any other accessories.
 
I suppose there must be something there draining things when the Isolator is on. The only thing I know of is the car radio taking milliamps for its memory. Obviously there must be something else too but as I normally faithfully throw that Isolator every time the boat is left I'm not too worried. Maybe when I get a visitor who is up on these things I will get them to test for me.
The launch has nothing else other than the car radio (which is never used). There's no VHF., Echo Sounder, electric bilge pump, GPS or any other accessories.

Might want to check for current leaks there then. Car radio drain is titchy and I guess the battery is pretty chunky.
 
Nope its a true real proper type boaty mystery . One for Lassie or the famous five i think .

Oooh, story time. A collective effort is called for I think.

Five Go Boating With Byron

One morning, Julian, Dick, George, Ann and Timmy the dog arrived at Byron's palatial residence. "Boat's down at the riverbank" said Dick. "Where else would it be" said Ann "we are supposed to be boating, so it must be floating." George looked pained at this. Julian was looking around for anyone who might be able to help. Although he and Dick knew about boats, George could row, but not use an engine and Ann was only a girl. "I know, said George" guessing what Jualin was thinking. Maybe there is someone around here who can help. It would be foolish to go on the river without knowing what we were about. After all, there might be anybody out there, even...villains.

next please.
 
Might want to check for current leaks there then. Car radio drain is titchy and I guess the battery is pretty chunky.

I had Byron's issue some time ago, and came to the same conclusion - small drain, couldn't possibly drain the battery; that is on a basis of ampere house consumed.

However, I read somewhere that a very small load can produce exceedingly small gas bubbles to "stick" to the plates and in effect make the battery appear to be dead. A quick belt with a decent battery charger disperses the gasses and hey presto the battery is restored to full capacity.

it worked for me - and I rewired the car radio - never got the issue again.

just a thought..
 
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