My battery's died again - second GSF battery that's done it. Now, GSF reckon there must be something up with my car for batteries to be dying this often - overcharging or not charging etc.. I reckon there must be something up with the batteries for them to die this often.
Am I right in thinking that basically the Alternator should be producing around 14V when running? Anything else I should be checking?
Have you checked the charging rate while it is under load? (Washers, hazards, lights, heater on full blast etc.)
Nope. Getting 13.8 volts at the alternator. By charging rate, do you mean volts or amps?
Volts. And what do mean by 13.8 volts at the alternator? Check across the battery terminals what the rate is. Then check with it under a full load. There should be little to no drop in voltage at all. A few tenths of a volt is acceptable but if you drop below 13.5v you're possibly in trouble.
I would expect the alternator to have some output resistance so I would expect to see a small drop of a few tenths of a volt between no load and full load. The wiring and connectors are going to contribute a few milli-ohms to the circuit as well.
As you say anything much below 13.5V across the battery and it's going take a long time to charge. Anything less than 13.2V and there'll be no charging at all. I've seen resistance on large crimp connectors where a volt has been dropped at a probable current of 20 Amps. A good way of burning yourself!
13.8V at the alternator terminal. By the time it gets to the battery it's dropped to 13.75V. I'll check load voltages in the morning.
Is the fan belt tight. John
When you say it died what do you mean exactly? Did you try recharging it out of the car? If it seems to recover then most likely there is a fault somewhere that's draining it when standing idle. If you can't get any current into it perhaps it's failed open circuit. How it behaves after "failing" might give a clue.
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