I've been running a daihatsu charade alternator for the last 12 months without any problem,charging up quite nicely.
Recently I noticed the voltage when charging had dropped to just over 13v and then I found that any load it would drop to something close to 12v.I checked the belt as the temperature also started to creep up once under load but the belt was fairly tight.I went out to the wreakers and got another alternator but found when I put it in I still had the same problem.
So what else could I be missing or have I just got unlucky and got a dud replacement.

Battery is less than 12 months old.

Don't know the makeup of the alternator but what about brushes? Most rotating electrical devices playup when the brushes are worn. - next thing to check

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Well I got hold of another alternator (freebie luckily) and I still have the same problem. Turn the lights on the voltage drops down to around 12v and the temperature moves up by a reasonable amount.
So it looks like its not the alternator unless I'm really unlucky.

Was the replacement alternator a known working alternator?

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

If it's not the alternator then it sounds like a dead short somewhere - any smoke? or loose earth connection or battery terminal

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Or a high resistance somewhere in the charging circuit?

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1967 Cooper S - new front bearings to do.
1965 Cooper S shell - Slow progress. No time or money!
1966 Deluxe- next rustoration!
Mk 2 & XJ6 Jags. Less said the better.

No but they looked in good condition and I'm working on the theory that 2 replacements having exactly the same problem as the original is unlikely.




No smoke .Battery terminals are tight.Its fine until I turn on the lights or even the indicators.Might have to try a process of elimination and disconnect things one at a time. I have to admit the wiring isn't brillant.