DIY : E92 M3 Alternator Replace

deansbimmer wrote

The "BMW original" alternator is made by Valeo, so its the same quality product without the BMW stamp on the label.

this mentioned Valeo alternator is this one for 283 usd?
https://www.fcpeuro.com/Parts/?keywords=12317837981

Lucas CR wrote

this mentioned Valeo alternator is this one for 283 usd?
https://www.fcpeuro.com/Parts/?keywords=12317837981

Hey, sorry nobody got back to you sooner. The Valeo part number is:
12317837981.

Turner is slightly cheaper, but if you think you will ever replace the alternator again then go for FCP.

Just changed my alternator with the help of a friend.

Adding a couple photos.

For that last radiator fan lower hose clip located on the passenger side, I found it easier to disconnect by reaching from the drivers side. Unless you have tiny hands/arms, it's impossible to get to it from the passenger side.

Also, did anyone else have oil/gunk all over the cables/connectors?

pbonsalb wrote

When I looked, the regulator was about $140. I bought the alternator with regulator for $230.

revisiting an old post.

Just to re-iterate, the regulator is approx $75 (valeo) and if often the culprit.

Regulator can be changed WITHOUT removing the alternator (access from underneath).

As always, disconnect battery negative lead in boot and ensure you DONT accidently close the boot. Suggest a cloth or similar over the lock.

Couldn't find a YouTube video so I thought I'd make one. Hopefully this helps someone out

Thank you for everyone who contributed to this thread. I’m about to change my alternator tomorrow. I’ve looked under the car and didn’t see any points of where I can remove the coolant hose from the clips under the car. Anyone have better way? Or just need to remove the shield?

If you have long skinny arms and don’t mind a few cuts you can get to the clips from the top. You can go down by the alternator side then run your hand blindly along the bottom and you can just barely get your fingers on them. The other option is to drop the underbelly. Good luck. It is doable. Remember when removing the alternator give the bolts a quick smack with a hammer before you fully remove them to drive the little threaded insert back into the housing or it will snag and not allow the alternator to clear from the bracket.

TX wrote

If you have long skinny arms and don’t mind a few cuts you can get to the clips from the top. You can go down by the alternator side then run your hand blindly along the bottom and you can just barely get your fingers on them. The other option is to drop the underbelly. Good luck. It is doable. Remember when removing the alternator give the bolts a quick smack with a hammer before you fully remove them to drive the little threaded insert back into the housing or it will snag and not allow the alternator to clear from the bracket.

Thank you for the info!

I could probably reach them but sounds like I might not be able to clip them back onto the hose after installing the alternator. My plan is to tap the bolts to force that cylinder out for removal. As well as being careful not to break the little nipple on the top coolant hose.

killakill wrote

Couldn't find a YouTube video so I thought I'd make one. Hopefully this helps someone out

Great video! Didn't have to replace the alternator yet but the day will come - thanks.

killakill wrote

Couldn't find a YouTube video so I thought I'd make one. Hopefully this helps someone out

Thanks for making this video. It was helpful. I did this job in about an hour earlier today. Made much easier thanks to this video and the discussions in this thread. Thanks all and happy holidays!

Btw...my alternator failure was spectacular. Few weeks of random inconsistent abs failure and battery discharge warning. Then one day, full Christmas tree within a couple minutes. Abs, edc, idrive shutdown, airbag light, speedo shutdown, power steering shut down, and finally car died. All good now. Old alternator looked original. 170k miles.

Can anyone confirm if the two 17mm alternator bolts are one time use and need to be replaced when installing a new one? I thought someone on here mentioned that so just want to be sure. Thanks yiu for this write up!

Just did this job today and it was easy getting the alternator out following the tips in this thread! My old alternator was have trouble charging (<14V) and occasionally threw a 278D BSD alternator missing code and the new one charges at 14.5V.

Here's a picture of why it helps to back out the bottom bolt by a few threads (a few mm) and hammer it in a few mm. The bottom bolt feeds into a captive nut (on the alternator) that gets pulled through the alternator casting press-fit hole and ends up clamping the face of the captive nut to the engine block. When you hammer the bottom bolt, you press this nut back in to free the clamp (and that surface is probably seized on some older cars).

See how this nut is flush on the new alternator. Do the tapping method on the bottom bolt and the alternator will fall right out without any prying or force, or you can rock the alternator back and forth once it starts getting loose from tapping. Leave the top bolt loosely screwed to support the alternator while you remove the bottom.