Ford fiesta - Alternator whining

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Thu 18 Nov 2021 20:09
Ford fiesta - Alternator whining - Joe tuzzer

Hi, I'm having trouble with the alternator on my car.

I replaced the original one because it wasn't charging anymore and replaced it with a Remanufactured one from a local company. This one worked and charged the battery but had a whining noise most noticeable at idle. I sent it back and got a replacement which made the excat same noise. I then got a 2nd hand original Ford one and the whining noise had gone but the 2nd hand one was on its last legs. I then went to Euro Car Parts and purchased a lucas alternator which is now making the same noise as the first ones. Any idea what it could be?

Is it something that I will have to live with or is there a solution other than swapping it out again?

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Thu 18 Nov 2021 20:44
Ford fiesta - Alternator whining - elekie&a/c doctor
Fiesta models came out in 1977 . How old is yours ?
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Thu 18 Nov 2021 20:47
Ford fiesta - Alternator whining - Joe tuzzer

2007

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Thu 18 Nov 2021 20:59
Ford fiesta - Alternator whining - elekie&a/c doctor
Ok , so this is fitted with a smart charge system . What voltage do you have at the battery terminals , engine running, and do you have a calcium battery fitted?
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Thu 18 Nov 2021 21:04
Ford fiesta - Alternator whining - Joe tuzzer

The voltage reads 14.2 with the engine running. It stays round the same when all the lights etc are on aswell. My battery is an exide premium battery that's around 1 year old.

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Thu 18 Nov 2021 21:37
Ford fiesta - Alternator whining - elekie&a/c doctor
That all sounds good. Do any of the battery terminals get hot with engine running ?
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Thu 18 Nov 2021 21:40
Ford fiesta - Alternator whining - Joe tuzzer

Not that I am aware of. Everything seems to be working spot on other than the electrical whining sound which is mainly at idle. Can't really hear it when driving. It's only St the really low rpms like sitting in traffic.

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Thu 18 Nov 2021 21:59
Ford fiesta - Alternator whining - elekie&a/c doctor
Don’t think I’d be too bothered about the noise . Just monitor the situation.
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Thu 18 Nov 2021 22:04
Ford fiesta - Alternator whining - Joe tuzzer

Fair enough. It's all working alright. Just find it weird how all the Remanufactured ones make the same noise even though they are different brands.

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Thu 18 Nov 2021 22:39
Ford fiesta - Alternator whining - elekie&a/c doctor

Very possibly reman units do not use genuine Ford sourced parts for re-building.

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Fri 19 Nov 2021 10:37
Ford fiesta - Alternator whining - Joe tuzzer

Probably that then. It's charging the battery and the bearing turns smoothly so that's good. Will just have to live with it by the sounds of it

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Fri 19 Nov 2021 11:25
Ford fiesta - Alternator whining - John F

Could the noise be from the belt/pulley interface? Try spraying it with a little water to see if it disappears.

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Fri 19 Nov 2021 12:33
Ford fiesta - Alternator whining - galileo

Could the noise be from the belt/pulley interface? Try spraying it with a little water to see if it disappears.

Does it have aircon, and if so is the aircon compressor driven by the alternator belt?

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Fri 19 Nov 2021 16:22
Ford fiesta - Alternator whining - Joe tuzzer

I have tried the water trick and it still makes the noise. Yes my car has aircon but today I put a screwdriver onto the alternator and the noise is definitely coming from the I side of the alternator. It's not a bad bearing sound, it's more of an electrical whine.

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Fri 19 Nov 2021 20:15
Ford fiesta - Alternator whining - Bolt

I have tried the water trick and it still makes the noise. Yes my car has aircon but today I put a screwdriver onto the alternator and the noise is definitely coming from the I side of the alternator. It's not a bad bearing sound, it's more of an electrical whine.

I always thought that was caused by a failed diode making the windings whine, but could be wrong, sometimes gets worse with higher revs. iirc can be checked by lower output at full load?

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Fri 19 Nov 2021 21:33
Ford fiesta - Alternator whining - Joe tuzzer

Is this a cause for concern? It doesn't seem to get worse at higher revs, as soon as the revs go above idle, the noise disappears. Its only really at idle that I can hear it.

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Fri 19 Nov 2021 22:14
Ford fiesta - Alternator whining - Bolt

Is this a cause for concern? It doesn't seem to get worse at higher revs, as soon as the revs go above idle, the noise disappears. Its only really at idle that I can hear it.

as it works ok leave it until a problem with charging occurs

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Mon 22 Nov 2021 17:00
Ford fiesta - Alternator whining - Joe tuzzer

An update on this. The whi I g was getting worse so I returned the alternator and got another 2nd hand one which has solved it. However I have noticed that the water pump has very slight play in it. You can only just feel the play but its not visible and there's no leaks. Is this alright?

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Wed 22 Dec 2021 08:54
Ford fiesta - Alternator whining - Armitage Shanks {p}

A Very short waft of WD 40, while it is running will sort it, temporarily at least, and should do no harm

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