flat battery ???

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bjdpend
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flat battery ???

Post by bjdpend »

I have a problem with my battery, believe it may be getting dragged down somehow, when i charge the battery up fully the camper starts no problem this will last for a day. after it has been driven for a 20 + miles and i leave it over night, it wont start, the starter motor will try and start. when i take a voltage reading its around 12.63v dc Can anyone help.

Thanks

Brian

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Hacksawbob
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Re: flat battery ???

Post by Hacksawbob »

12.6v isnt too bad for a standing battery.

What does it read when driving, ie alternator output?
Remove the negative strap when stopped and then tap it against the battery post and look for a spark to see if there is something still draining gthe battery when stopped, you can do this with a bulb too which is a bit more easy to see. If there is a spark then start going through the fuses to isolate which circuit the drain is on. Start with the cig lighter as this has the stereo usually, a likely candidate. As always check your earths for corrosion free contacts.

It could be that your starter motor is sticking sometimes rather than batt fault?
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BOXY
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Re: flat battery ???

Post by BOXY »

Are you measuring the voltage while the engine is cranking over. If it drops below 9v when cranking, the battery may be past it. When you measure the voltage of a battery you should really do it 24 hours after charging to let the surface charge dissipate. If you check it straight after charging the result can be a lot higher.
2ltr Aircooled CU with twin Solex's & originally a 009 dizzie, but now back to standard.

bjdpend
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Joined: 20 Aug 2010, 19:43
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Location: Gosport, Hants

Re: flat battery ???

Post by bjdpend »

I will look at both these and will let you both know the results.

Thanks

Brian

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