Whining alternator problem

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Bart
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Whining alternator problem

Post by Bart »

Hi, long time since I have posted on here.

I am having a weird problem the the alternator on my 1996 serp Chimaera. Started whining a few weeks ago. Suspected the alternator, so replaced it, and also the tensioner.

However, the whining remains, and it is unmistakably coming from the new alternator. Initially suspected it may be my usual bad luck and have got a duff new alternator, as it is a generic pattern part. However, this morning, I briefly ran it with the alternator disconnected and the noise goes away completely, which makes me wonder if an electrical fault is causing it to be overloaded. If I run it and disconnect a fuse labelled 'fuel pump and c/d/l feed', it continues to run for two seconds or so without the noise. Not sure what c/d/l feed is, but could it really be the fuel pump causing the alternator to whine? It reads 14.4V on tickover, and the battery is Varta that is only two years old. Starts and runs fine apart from the noise.

Just very strange that a brand new alternator has the exact same noise.

Any suggestions appreciated.

Cheers, Adam



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Ian Anderson
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Re: Whining alternator problem

Post by Ian Anderson »

Where is your fuel pump? Could it be letting go causing it to whine? If it has ever sucked air it will start making a whine!

Ian
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.

Bart
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Re: Whining alternator problem

Post by Bart »

The pump is behind the back wheel, but it is definitely the alternator whining. Another suspected culprit is my starter motor, if that has a short in it maybe that is causing a massive load on the alternator? The starter is only 6 weeks old though.

I find it very suspicious that the noise goes away if I disconnect the heavy cable on the alternator and run it without. Unless the new alternator is so duff that even the slightest load on it causes it to whine. Don't want to have to send the new alternator gack, only to find a 2nd new one has the same problem.

jenand40
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Re: Whining alternator problem

Post by jenand40 »

I would try changing the serpentine drive belt.

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