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Anyone know the part number for Roadster S alternator?

From the parts catalogue - if you don't have a copy send me a PM with your email address and I'll send you a PDF version

You may find it cheaper/easier/faster to remove it and get it reconditioned.

Thanks Perry
I managed to find the parts catalogue earlier.
Seems its not going to be easy to get one so your suggestion might be best option.

Here's a picture if it helps. I had my one refurbished a few years back.

Thanks folks - Confirmed my alternator is faulty so need to try and locate one if possible.

If anyone knows that would be great.

Looks like will need to be refurb though.

Did find online a bit of debate if it was same unit as Alpina B3? Anyone able to confirm?

From memory (and it was a while ago) I could only source the "B3" alternator outwith the dealer network and whilst it appeared correct, when I got it, it had a different connector. This is why I went down the refurb route.

Picture of the "B3" one attached. I imagine the correct RS one can only be sourced from BMW if you want to buy new.

Gee wrote: ↑Wed May 24, 2023 8:06 pm From memory (and it was a while ago) I could only source the "B3" alternator outwith the dealer network and whilst it appeared correct, when I got it, it had a different connector. This is why I went down the refurb route.

Picture of the "B3" one attached. I imagine the correct RS one can only be sourced from BMW if you want to buy new.

Thanks, I found a couple of companies selling the B3 one with same part number as ours.
Saves me making same mistake.
Spoke to BMW yesterday, who were pretty hopeless.
Once I had the usual battle of them telling me my car was an E46, then a 3.0i, then me telling them they need to use prefix 9147 to search Alpina parts we eventually got a price of £905.
None in stock, can't give delivery date.
Refurb it is.

MefiEcosse wrote: ↑Thu May 25, 2023 7:03 am Thanks, I found a couple of companies selling the B3 one with same part number as ours.
Saves me making same mistake.
Spoke to BMW yesterday, who were pretty hopeless.
Once I had the usual battle of them telling me my car was an E46, then a 3.0i, then me telling them they need to use prefix 9147 to search Alpina parts we eventually got a price of £905.
None in stock, can't give delivery date.
Refurb it is.

Refurbishment of something like an alternator isn't a 'bad thing', after a decent refurb it should look and perform like new.

I have my Alternators rebuilt by a local rebuilder had problems getting replacements elsewhere they supplied two, first oine was setting a code for the varable charging rate, returned that oine and they sent another that had the wrong pully on it, gave up and sent that back and had a refund. Then found the local guy who rebuilt my duff one that wasn't charging, he put a oem diode pack in it. I had been running the car with a used one so the rebuilt one was on the shelf as a spare. Low and behold the used one failed so the rebuilt one was put on and works fine. The now duff used one is currently with my local man for a rebuild. Rebuild cost me circa £60 far cheaper than anywhere else.
Carl's Starters and Alternators located in Tredegar, South Wales
https://www.yell.com/biz/carl-s-starter ... r-4833863/

What were the symptoms of your failing alternator Tim ?

My battery light occasionally remains lit after starting but as soon as I rev it to 2000 revs it goes out and stays out.
I’ve replaced the battery and it’s made no difference.
Tredegar is on my regular routes so a rebuild may be the right option for me too.

Why not just pop in a new voltage regulator, 90% of the time that's the reason for failure. Remove it and check the armature for excessive wear. If the armature looks OK, just replace the regulator. https://www.fcpeuro.com/products/bmw-vo ... f00ma45219

Been sent some info, apparently E46 2.2 alternator does the job.
Someone else with Roadster S has sent me the part number fitted on theirs, which is for E46.
Been busy so not been able to sort mine out yet, hopefully I'll make some progress this week.