So...

[pao7psb]

...since the winter I have been having battery trouble, best summed up by my experience last weekend - on Friday I spent most of the day charging the battery on trickle charge until it was fully charged or thereabouts, 3 days later after a 400 mile round trip to the National and back it was flat as a pancake. So what is knackered, is it my battery, my charging system or both?

Cheers,

Paul.

[mike.perry]

If your headlights brighten when you rev the engine then your charging is OK. It is worth checking that your fanbelt is tight. This time of year it is unlikely that you are using more battery power than the dynamo is charging. I would say that the battery is on its way out. A supplier should be able to test it before you buy a new one. Meanwhile out with the starting handle

[beero]

If you can get hold of a voltmeter then put it across you battery with then engine off, you should get 12v. Then turn the engine on and rev it slightly and the voltmeter should show more voltage. If less, then it is not charging.

[bmcecosse]

Get a small multi meter from Maplins - set to DC and measure the battery volts with the engine at a fast idle. Should be ~ 13.8 volts which indicates the dynamo (or alternator) is charging. Compare with volts when engine not running - and again with headlamps switched on - with engine running fast and not running. I would say that if it restarted your car to come home from the event -then the battery is probably ok - but there could be a charging problem. Checking the fan belt condition and tightness is indeed a good starting point! Other possibility is - something left on - draining the battery ?