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falcodub

Alternator issues

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Hi all

Some urgent help needed as my 2002 m5 is booked in for welding Friday but at present it's not working

 

13 months ago my alternator packed up. 

Had it refurbished and a new battery as that got toasted. 

 

Fast forward to now and its not charging again. 

 

An exchange unit was sourced as a refurbished lucas item and I have the same issue. 

 

Wiring and earth's checked. 

Can it only be a duff alternator or is there something else?? 

 

Brand new m5 alternator is 1100 quid from bmw

 

Refurbished one was a third of that. But of course doesn't seem to work. 

 

People saying that they don't seem successful when refurbished. What makes it so difficult to do on these? 

 

Help!!!!! 

Edited by falcodub

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I'm always suspicious of 'recon' stuff. Did they fit a new voltage regulator? That's the bit that normally fails and it'll be a standard Bosch part as used on every other air cooled E46 or E39 120a alternator.  Other V8's on that era were water cooled but the VR might be the same.

 

Lucas, whilst never a marque known for quality, is now a name on a box in which all kind of shite arrives. 

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1 hour ago, Sir Anthony Regents-Park said:

I'm always suspicious of 'recon' stuff. Did they fit a new voltage regulator? That's the bit that normally fails and it'll be a standard Bosch part as used on every other air cooled E46 or E39 120a alternator.  Other V8's on that era were water cooled but the VR might be the same.

 

Lucas, whilst never a marque known for quality, is now a name on a box in which all kind of shite arrives. 

 

I'm sadly at a loss on what to do. 

Lottery on replacement recon unit. 

An alternative recon unit. 

Or over a grand for a genuine new one

 

I could buy a regulator but why am I doing this for a recon alternator!? 

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3 hours ago, Sir Anthony Regents-Park said:

Because it's £25 and it might fix the car? That's old cars for you. 

BMW genuine price is 250 quid. 

 

I've ordered a beru one from Germany 

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9 minutes ago, falcodub said:

 

I've ordered a beru one from Germany 

 

Got a link for the Beru voltage regulator?

 

I'm putting together a repair/rebuild kit for my (still healthy) alternator which will sooner or later require a rebuild.

 

Definitely not keen on the aftermarket rebuilt alterrnators!

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I had to have a new alternator back in 2017, it came to £387, my indy sourced it but I don't know what he actually fitted, all it says on the invoice is "1 alternator 120 amp £387" 

 

I remember being chuffed to bits at the time as on Realoem they were coming up at $999... 

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30 minutes ago, DepthHoar said:

 

Got a link for the Beru voltage regulator?

 

I'm putting together a repair/rebuild kit for my (still healthy) alternator which will sooner or later require a rebuild.

 

Definitely not keen on the aftermarket rebuilt alterrnators!

 

https://m.autodoc.co.uk/beru/7020050

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Thanks for the link, Falcodub.

 

Managed to find a UK supplier (official Beru agent) for the voltage regulator and a little bit cheaper, too, at £41 delivered, although it's a back order part so I I'll be waiting a week or so.

 

Here's the voltage regulator:

496433158_BeruVR.png.ca91f93e0a1e63c7d2ba924def29381f.png

 

...and here's the link to the UK supplier: https://www.sparkplugs.co.uk/beru-alternator-voltage-regulator-ger088

Edited by DepthHoar

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7 hours ago, DepthHoar said:

Thanks for the link, Falcodub.

 

Managed to find a UK supplier (official Beru agent) for the voltage regulator and a little bit cheaper, too, at £41 delivered, although it's a back order part so I I'll be waiting a week or so.

 

Here's the voltage regulator:

496433158_BeruVR.png.ca91f93e0a1e63c7d2ba924def29381f.png

 

...and here's the link to the UK supplier: https://www.sparkplugs.co.uk/beru-alternator-voltage-regulator-ger088

Ah

Good find. 

Sadly I'm waiting on the autodoc one now so you'll probably see yours before I do. 

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The frustration continues. 

New beru regulator fitted. No output. 

Refurbished one bought from eurocarparts for 350 quid. 

Fitted to car. No output. 

 

Took both to a specialist and neither output any voltage. 

 

He reckons the Rectifier has failed and it isn't available for the m5 alternator. 

This all explains why nobody has much success refurbishing these alternators. 

 

Where I go from here is lucky dip second hand (if I can find one) 

Brand new from bmw for around 1100 quid or another refurbished one from West Lancs auto electrics for 150 ish. 

 

They can't confirm exactly what they do for a refurbished one but 18 months warranty is something I guess. 

 

Anyone got an m5 alternator for sale talk to me!! 

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You might want to have a look at this: https://www.ebay.co.uk/c/1645444878

 

As far as I can tell that is the correct Bosch OE rectifier for the E39 M5 alternator.

 

I've bought Bosch stuff from KMS before and they are a legit Bosch distributor.

 

But do check the rectifier compatibility before you commit to buying.

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5 minutes ago, DepthHoar said:

You might want to have a look at this: https://www.ebay.co.uk/c/1645444878

 

As far as I can tell that is the correct Bosch OE rectifier for the E39 M5 alternator.

 

I've bought Bosch stuff from KMS before and they are a legit Bosch distributor.

 

But do check the rectifier compatibility before you commit to buying.

Cool. 

Will check it out and see if I can find anymore compatibility details 

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Lifted this from Wood Auto (I have an account with them):

 

Bosch2.thumb.png.5eb9056e604d4dc2ed1579b07d1e3972.png

 

Bosch3.thumb.png.260f040c4c55331117489354a77c6873.png

 

Untitled.thumb.png.4e72636c5688c4a62e77cc0955904fe1.png

 

The M5 alternator is BMW part number 12311407440

 

The Bosch part number for the M5 alternator is 0123515029, which cross references with (meaning same as) the Bosch 0123515030 alternator.

 

According to 'The Bill of Materials for Bosch 0123515030' (on the last image) the correct Bosch Original replacement rectifier is BOS1127319831, which is the one I referenced on eBay.

 

Plan B:  A Bosch remanufactured alternator (reman by Bosch themselves) from Rockauto in the USA is currently £260 delivered to the UK. There'll be VAT & import duties in addition to that but it'll still be a awful lot less than £1k. (Estimated total cost £320, if VAT is 20% and import duty 2.5%. Some couriers charge a handling fee, too.)

 

 

Edited by DepthHoar

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Update on this.. 

Rectifier replaced and all is now well. 

 

Interestingly the Beru regulator I oredered was made in China and didn't work. Hopefully I can return it as it was 50 quid. 

 

Hopefully this now lasts longer than 12 months this time 

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Another update. 

After having a new Rectifier and check over alternator was working fine. 

 

Went to drop it off for welding today and a gentle drive over (the wife was following) with one red line flurry near the end and the car cut out completely and now the battery light is back on. 

 

Can't check anything until its back from the welders but the alternator looks to of died again  

 

£1100 on a new bmw one is getting closer 

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16 minutes ago, DepthHoar said:

Import a Bosch original remanufactured one from the USA. See 'Plan B' in my last but one post. Approx £320.

 

Ah yes thanks for reminding me. 

I shall investigate it further once its welded

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Is there anything in the wiring that could cause a problem with the alternator? 

As in shorting it out so it fails? 

 

Earth's and wiring been checked and all appear to be fine. 

 

Importing an alternator from USA is an option. But I am not 100% certain they are refurbished with bosch inners. 

 

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