Bad battery behaviour.

Thresher

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My 3 year old 60 amp starter battery suddenly died. It was leaking acid from the top so I've replaced it.
What I don't understand is why it didn't give any warning that it was on the way out. 3 years of instant engine starting then when I push the start button I just get a click and then the switch panel light goes out. With a car, you know the battery is on the way out because the starter motor turns the engine over more and more slowly. Can anyone tell me what is going on?
 

B27

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Leaking acid out of the top suggests 'boiling' dry by over charging or some other abuse?
I would check the charging voltages etc.
 

Sandy

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I arrived onboard the boat last Friday to find a small glass of water had turned into an ice cube. While ideal for my evening sundowner, it did indicate how cold it had been. The boat is on the hard in Cornwall.

Do you have any records of how cold your boat got? Victron tells me that the area where the batteries are got down to 0°C the saloon will have been colder.
 

Thresher

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My 3 year old 60 amp starter battery suddenly died. It was leaking acid from the top so I've replaced it.
What I don't understand is why it didn't give any warning that it was on the way out. 3 years of instant engine starting then when I push the start button I just get a click and then the switch panel light goes out. With a car, you know the battery is on the way out because the starter motor turns the engine over more and more slowly. Can anyone tell me what is going on?
Oh. It's just failed to start with the new battery (it was OK an hour ago). It starts ok with jump leads from the domestic battery. I think I have a bad connection issue (and now a spare battery).
 

Refueler

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Leaking at the top ?? Out of the small vent pipe that some have - or from a crack or hole ??

Anyway - if at top - sounds like an overfilled battery ......

Was it frozen at any time ?? If so - then battery plates will be shot ... and often case splits.

Lead Acid battery freezing - will normally require serious low temp - but if the battery is discharged - then it can freeze at a moderate low temperature ... I've had that happen unfortunately.
 

William_H

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Even at normal temperatures a battery can fail to start the (car) engine with no warning. Even after a long run charging. I have had it happen twice with car batteries. So not necessarily any warning although usually as you say a progressive loss of enthusiasm on cranking. ol'will
 

footsoldier

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Oh. It's just failed to start with the new battery (it was OK an hour ago). It starts ok with jump leads from the domestic battery. I think I have a bad connection issue (and now a spare battery).
It is a possibility that you also have a coincidental issue of a poor connection, which can be easily investigated, but as B27 suggests, you need to investigate the original battery failure - charging voltage etc - or you could end up with your shiny new battery also knackered.
 
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Thresher

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It is a possibility that you also have a coincidental issue of a poor connection, which can be easily investigated, but as B27 suggests, you need to investigate the original battery failure - charging voltage etc - or you could end up with your shiny new battery also knackered.
I am quite sure that is an old connection problem come back to haunt me 3 years later and it only happens when the starter battery is less than 100%. I condemned the old battery although it was reading 12.7v because of an almost unnoticeable leak and the new one had been in the shop for a long time and was only reading 12.5V when I bought it.
 

Farmer Piles

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Could be that the leads to the starter motor are too small - a not uncommon problem in boats. Both me and my mate are upgrading ours as they are deemed to be too small a core and we both have sluggish starting.
Also, batteries do just fail sometimes, the plates in a cell can just buckle or warp and it knackers the who;e battery.
 

Sandro

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Apart from freezing and leaking, I noticed that, as the OP says, good old time car batteries used to give early warnings of decading, whereas nowadays batteries work properly until last minute and suddenly die..
No idea which could be the inner difference.
 

William_H

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I am quite sure that is an old connection problem come back to haunt me 3 years later and it only happens when the starter battery is less than 100%. I condemned the old battery although it was reading 12.7v because of an almost unnoticeable leak and the new one had been in the shop for a long time and was only reading 12.5V when I bought it.
The critical voltage test is the actual voltage of the battery when cranking the engine. Typically around 9 or 10 volts for a good battery. Much lower for a bad battery. You need to measure at the actual battery terminals. ol'will
 

QBhoy

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apart from the leaking, the vastly different utilisation between a car and a boat etc etc...A huge factor with influence here, is the temperature. Apart from the cold having a habit of killing a battery that's sat mostly dormant, the cold has a huge influence on the engine and its components. The engine will be extremely tight, with regards to her components interfering fitting tolerances. The oil will be viscous too. This all combined with a less than decent battery, means she will show some real resistance and reluctance to turn over easily. Hope that helps
 

Thresher

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Apart from freezing and leaking, I noticed that, as the OP says, good old time car batteries used to give early warnings of decading, whereas nowadays batteries work properly until last minute and suddenly die..
No idea which could be the inner difference.
Yes, thank you Sandro. That was the question that I asked.
 
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