Jake Posted March 6, 2009 Share Posted March 6, 2009 Seems like the alternator on my 53 plate e46 M3 coupe had died. I got the red battery warning light on the dash the other night and then today (first time I've driven the car since the warning light came on) the car has died with a flat battery. After the warning light came on, but before the battery went flat, I checked it with a voltmeter and it was show 12v regardless of whether the engine was running or not - that indicates the alternator, right? Should I get a genuine new one from BMW (£489) or would a reconditioned one, eg http://tinyurl.com/dendgj for £135 probably be ok? Also, anyone know if these are reasonably straightforward to fit for a normal standard home mechanic? Thanks. Quote Link to comment Share on other sites More sharing options...
SteveR Posted March 6, 2009 Share Posted March 6, 2009 Hi Jake. My mate has changed the serpentine belt on his and a mate's E46 330Ci. Want me to ask him for tips that might help you or is the M3 likely to significantly different? Quote Link to comment Share on other sites More sharing options...
DannoSupra Posted March 6, 2009 Share Posted March 6, 2009 Also check the fuses to the altenator, even the big 250-500A Megafuses! It does sound like a duff altenator, will ask tomorrow, my mate is a BMW Mechanic Personally on a car like an M3, i'de get a Genuine BMW altenator! Quote Link to comment Share on other sites More sharing options...
n boost Posted March 6, 2009 Share Posted March 6, 2009 Alternator seems to be a common problem on the m3's. I know a few guys who have had theirs reconditioned for approx £80-£100 and they seem to be fine. They should be fairly straight forward to fit and you may find a diy on the net somewhere. Quote Link to comment Share on other sites More sharing options...
Scoboblio Posted March 8, 2009 Share Posted March 8, 2009 (edited) I checked it with a voltmeter and it was show 12v regardless of whether the engine was running or not - that indicates the alternator, right? Yup, the voltage should go up when the engine's running because the alternator should be putting extra v's into the battery. I was once told that a refurbished alternator is about as good as a new one since they don't really break as such, just wear out on on the insides which are then replaced. Then again, the guy who told me that sold refurbished alternators. Edited March 8, 2009 by Scoboblio (see edit history) Quote Link to comment Share on other sites More sharing options...
Guest Garfy Posted March 8, 2009 Share Posted March 8, 2009 first of all check that the alternator has a good earth Quote Link to comment Share on other sites More sharing options...
DannoSupra Posted March 8, 2009 Share Posted March 8, 2009 first of all check that the alternator has a good earth It should do, it earth's itself through where it bolts to the engine They are a straight forward swap, sometimes a PAS pipe gets in the way on some models, and can be a pain Hope this helps Quote Link to comment Share on other sites More sharing options...
AshBhp Posted March 8, 2009 Share Posted March 8, 2009 (edited) You need to now if you have 120amp or 140amp alternator, PM last 7 digit of VIN number and I'll check for you. Not to bad to change. Edited March 8, 2009 by AshBhp (see edit history) Quote Link to comment Share on other sites More sharing options...
n boost Posted March 8, 2009 Share Posted March 8, 2009 I think there are 2 types as mentioned above and also 2 types of batteries depending on how specced the car is. There was a heavy duty battery and alternator fitted to models which had a high spec and therefore put extra strain on battery and alternator. Quote Link to comment Share on other sites More sharing options...
Jake Posted March 10, 2009 Author Share Posted March 10, 2009 Oooo, this is getting expensive. I put the car into my local BMW specialist and told them to fit a genuine bmw alernator and to MOT the car. They called me this afternoon. Apparently it needs new rear springs and two new front suspension arms (the bushes are gone they said and the reckon they ain't removable) Total bill ... £1386.34 ! Quote Link to comment Share on other sites More sharing options...
Havard Posted March 10, 2009 Share Posted March 10, 2009 Oooo, this is getting expensive. I put the car into my local BMW specialist and told them to fit a genuine bmw alernator and to MOT the car. The called me this afternoon. Apparently it needs new rear springs and two new front suspension arms (the bushes are gone they said and the reckon they ain't removable) Total bill ... £1386.34 ! FFS!! *Closes Pistonheads Classifieds For M3's*.... H. Quote Link to comment Share on other sites More sharing options...
Jake Posted March 10, 2009 Author Share Posted March 10, 2009 I was this close to PXing it for an RS6 the other day. Maybe I should have - and let somebody else have this bill. Quote Link to comment Share on other sites More sharing options...
n boost Posted March 10, 2009 Share Posted March 10, 2009 Price sounds about right. My current m3 had the front arms replaced on its last mot and also a trailng arm bush etc and have a reciept for £1100. Have you seen parts prices for the rs6? They should change the rear springs for you free of charge as this was one of the recalls issued by bmw, give bmw customer services a ring and they should sort it. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.