Flat Battery!

[meehaja]

Simple on I know, but...

Due to a combination of bad weather and ill health the van hasn't moved (at all) for about 3 months. Wheels still turn fine etc, but the battery is flat. Unfortunately i parked it facing up hill so I can't roll it down the hill and start it that way. I've got some jump leads and it is starting to try to start but its not enough (starter motor not really making an effort) Do i need to leave it on charge longer (tried 1 mins hooked unto wifes C3) or is it a case of battery out and get an external charger, or do i need a new battery?

I know its a really simple one, but in the past my cars have started straight away from jumping, though they have never been left this long!

Thanks

jimmy

[kevtherev]

The cold weather has killed the battery you're trying to jump.
Best use a fresh battery (any) to jump from your jumper

[meehaja]

Do you mean I need a new battery for the van?

[kevtherev]

do you have a multimeter to check the voltage of the battery? (below 10v is dead)
but for the time being can you borrow one to start the van?
because... routing the jump through a dead battery won't work, it's not the same as a low battery... it's soaking up the power you need

Take it to a garage and have it checked unless you have the equipment.

could you remove it and charge it to full overnight?
then leave it for a few hours if it falls below 12.6 volts it's shagged

[meehaja]

ah ok, I'll look into that. Its a fairly new battery so hopefully its not dead! I'm going to get a charger tomorrow (why do i always leave buying a tool until i need it?) and we'll see how it gets on! Thanks for your advice

[kevtherev]

being less than three years old will be in your favour
But.. here is a more technical reason...
When a battery is fully charged it has a specific gravity of 1260 (this is the measurement of sulphuric acid) this measurement can be checked with a hydrometer, when the battery discharges the sulphuric acid goes through a chemical reaction and becomes more like water and would measure a specific gravity of 1000.

If water freezes at zero deg C and you battery was completely discharged, then it is fair to say that your battery froze solid like a ice cube.

Once this happens, the battery is 99% unrecoverable. Your trickle charger would be useless on the battery.

[Cazz]

My bus battery had gone flat the other day, we went to jump it from the car battery, we found that was even flatter than the bus one, in fact it was dead.

We loaded it into the dogs pushchair and walked in the snow and ice to the local battery place, he tested it on his magic meter thing and confirmed it had, had it, new battery purchased, walked back home again.

Battery installed in car, car started, bus jump started at last. Then we could go and buy a fridge in the freezing cold, an oven would have been warmer

Good luck with your battery Jimmy, I hope my story at least made you laugh.

And Kev I love all your facts on the various subjects, some very useful information

[monkeyboy]

Should have a warranty with the battery if you can find your receipt!

Think mine was 3 years.