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Old 9th March 2017, 20:58   #11
boink
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I'll try that and if it works I'm asking for your address and sending a crate of beer over! If only I hadn't loaned my charger to daughters ex boyfriend.
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Old 9th March 2017, 21:04   #12
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I'll try that and if it works I'm asking for your address and sending a crate of beer over! If only I hadn't loaned my charger to daughters ex boyfriend.
I've loaned things out over the years and quite often they've not come back or been returned damaged and of no more use.

Finally I have now STOPPED lending anything any more.----- Go get your own I say.--
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Old 11th March 2017, 11:26   #13
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Charged battery overnight (according to my cheap multimeter got to 12.27 which seems a bit low but 3 year old battery). Re-attached to car making sure connections sound. Tested with engine running and reading at 11.85. Noticed that there was a noticeable, slightly 'slushy' sound coming from the belt, which could tie back to the car getting soaked? Not whining but something I've not noticed before.

At 2000 revs the reading didn't jump at all. Same reading as when idling. No screeching or whining noise from belt at increased revs.

Battery light staying on.

Time for a new alternator or regulator pack or new battery and try that first? I'd have a go at tightening the belt first but doesn't look too straightforward and I've not got ramps or a decent jack.
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Old 11th March 2017, 11:53   #14
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Just tried changing fuse 36, no difference, however when revving really high 3- 4000 I noticed the battery light go off.

Wife back in the car with foot down and lo and behold, the alternator starts charging up to 1400 only under high revs.

I'm guessing now its just a loose or worn belt. Grateful as ever for guidance from people who know more than me --and the garage, who said alt was completely dead...it seems not!
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Old 11th March 2017, 14:18   #15
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What strikes me as odd is that it took two hours to fail after you drove through the water.

The alternator would have been hot and any water on or in it would have dried out quite quickly.

Maybe just the brush gear has failed. The garage you went to would have just checked output and said the whole thing was shot. ( PROFIT.-- )
My very exact thought, water on a hot running alternator, equals death, I would check all leads first traced down from battery, clean dry and refit, get someone to help you start it with a new battery and check with multimeter alternator output.
Just out of interest what exactly did the garage do to 'diagnose' a 'dead' alternator?.
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Old 11th March 2017, 14:40   #16
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Charged battery overnight (according to my cheap multimeter got to 12.27 which seems a bit low but 3 year old battery). Re-attached to car making sure connections sound. Tested with engine running and reading at 11.85. Noticed that there was a noticeable, slightly 'slushy' sound coming from the belt, which could tie back to the car getting soaked? Not whining but something I've not noticed before.

At 2000 revs the reading didn't jump at all. Same reading as when idling. No screeching or whining noise from belt at increased revs.

Battery light staying on.

Time for a new alternator or regulator pack or new battery and try that first? I'd have a go at tightening the belt first but doesn't look too straightforward and I've not got ramps or a decent jack.
Unless your charger is not doing its job then that low voltage after an overnight charge says bad things about your batteries internal condition.

There is a fair chance that it's reached the end of its useful life.---

You should see between14 and 15 volts on tick over.
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Old 11th March 2017, 18:51   #17
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So the alternator only supplying a charge at really high revs indicates a replacement brush kit rather than a new aternator? Going to pick up a decent new battery tonight and give it another go tomorrow. I'll have to do what I can re checking and drying connections as seems pretty hard to access them.
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Old 11th March 2017, 19:31   #18
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Usually engine heat will after a short while dry off any water that was splashed about when driving through a flood.



PS. All floods should be driven through at a VERY LOW speed as you are in a car and not a boat.-----------
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Old 11th March 2017, 22:11   #19
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Worst case scenario mate get a good used alternator from one of the breakers on here and fit it yrself
It's not that difficult
Just take your time
Regards
Chris
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Old 11th March 2017, 23:14   #20
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Ta for all suggestions above. Fitted a couple of injectors a little while back so as long as It's not too technical a job I'll have a go at fitting an alternator. My question really is why the alternator should start to kick in at really high revs... but not be contributing when idling or at 2000 revs.

The garage just popped a multimeter on to the battery and because there was no evidence of charging at either tick over or mid range revs, decided the alternator must be a write off. Not a suggestion that they could look at wiring connections, slipping gelt or anything else, including regulator replacement.
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