A while ago someone on here posted some guidelines for testing batteries. It went something along the lines of this:
Over 13 volts or so when running = alternator OK. Battery should settle to xx volts after running. The next morning, the battery should be above xx volts.
Unfortunately, I can't find it on google. Any chance of a repost?
Give battery a full charge with a modern electronic charger. Let battery settle (disconnected from car) for 12 hours. Battery should ready 12.6V or more. 12.4V=75% charge. 12.25V=50% 12.05V=25%
Ta.
Or if you ignore the Americans paranoia about melting alternators
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