Looking for alternator replacement DIY for 335 with N55

FrenchX3 · 02-27-2018, 12:33 PM

I have a 11' 335 xdrive sedan with a "charging malfunction" warning message. Had the battery tested and it's drained but otherwise fine. I'm measuring voltage at the battery of 11.5 when not running. I start the car and it jumps up to 14.5 which tells me the alternator is working. Then after about 2-3 minutes of idling it drops back down to 11.5 again. So the alternator or regulator is likely on the outs. I just bought a new alternator and looking for a set of DIY instructions or a video showing the process to replace it. Was unable to find anything on this forum or other forums or Youtube.... Anyone have any ideas where I might find one?

techwhiz · 02-27-2018, 04:18 PM

Quote:

Originally Posted by FrenchX3

I have a 11' 335 xdrive sedan with a "charging malfunction" warning message. Had the battery tested and it's drained but otherwise fine. I'm measuring voltage at the battery of 11.5 when not running. I start the car and it jumps up to 14.5 which tells me the alternator is working. Then after about 2-3 minutes of idling it drops back down to 11.5 again. So the alternator or regulator is likely on the outs. I just bought a new alternator and looking for a set of DIY instructions or a video showing the process to replace it. Was unable to find anything on this forum or other forums or Youtube.... Anyone have any ideas where I might find one?

If you hand't already bought the alternator, I would have told you to buy a regulator. They can be had for about $50 and take about the same amount of time as changing the air filter. Can be done on car.
I hope you find the DIY. Good luck.

Efthreeoh · 03-01-2018, 09:16 PM

I looked at realoem.com to double check. The N55 has a similar alternator mount to the N52. I published a DIY for replacing the alternator on the N52. It should work for the N55 because both engine blocks are of similar design.

GLWI

http://www.e90post.com/forums/showth...8#post21412938

FrenchX3 · 03-02-2018, 09:57 AM

Thanks for the replies guys....

Techwiz - I was thinking exactly what you posted and have since come across a rebuild kit that includes the voltage regulator and bearings for $58. I know I can replace it in place but I've already got a new alternator so I'm committed at this point. The problem is getting the old one out seems to be a bit of a jigsaw puzzle. I've removed the four mounting bolts but can't seem to wedge it out from in between the oil filter housing and the A/C compressor. I'll keep looking for tips or DIY. I haven't found anything as of yet. I'm planning on doing the OFHG at the same time so I might do that first to gain more access for alternator removal.

Efthreeoh - Thanks, I checked out the DIY for the N52. It doesn't appear to be the same (I know the N54 is not the same mounting set up either). I'll post any insight I gain going through this process.

delmarco · 08-07-2018, 02:42 PM

Quote:

Originally Posted by FrenchX3

I have a 11' 335 xdrive sedan with a "charging malfunction" warning message. Had the battery tested and it's drained but otherwise fine. I'm measuring voltage at the battery of 11.5 when not running. I start the car and it jumps up to 14.5 which tells me the alternator is working. Then after about 2-3 minutes of idling it drops back down to 11.5 again. So the alternator or regulator is likely on the outs. I just bought a new alternator and looking for a set of DIY instructions or a video showing the process to replace it. Was unable to find anything on this forum or other forums or Youtube.... Anyone have any ideas where I might find one?

Usually a dying battery is what takes out an Alternator or rather the Alternator should out live a couple of batteries before it goes.

At any rate this should help you understand the scope of work involved:

02-27-2018, 12:33 PM	#1
FrenchX3 Registered 2 Rep 3 Posts Drives: 2011 335 Xdrive Sedan Join Date: Apr 2017 Location: Milford, NH iTrader: (0)	Looking for alternator replacement DIY for 335 with N55 I have a 11' 335 xdrive sedan with a "charging malfunction" warning message. Had the battery tested and it's drained but otherwise fine. I'm measuring voltage at the battery of 11.5 when not running. I start the car and it jumps up to 14.5 which tells me the alternator is working. Then after about 2-3 minutes of idling it drops back down to 11.5 again. So the alternator or regulator is likely on the outs. I just bought a new alternator and looking for a set of DIY instructions or a video showing the process to replace it. Was unable to find anything on this forum or other forums or Youtube.... Anyone have any ideas where I might find one?
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03-01-2018, 09:16 PM	#3
Efthreeoh General 17205 Rep 18,696 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	I looked at realoem.com to double check. The N55 has a similar alternator mount to the N52. I published a DIY for replacing the alternator on the N52. It should work for the N55 because both engine blocks are of similar design. GLWI http://www.e90post.com/forums/showth...8#post21412938 __________________ A manual transmission can be set to "comfort", "sport", and "track" modes simply by the technique and speed at which you shift it; it doesn't need "modes", modes are for manumatics that try to behave like a real 3-pedal manual transmission. If you can money-shift it, it's a manual transmission. "Yeah, but NO ONE puts an automatic trans shift knob on a manual transmission."
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03-02-2018, 09:57 AM	#4
FrenchX3 Registered 2 Rep 3 Posts Drives: 2011 335 Xdrive Sedan Join Date: Apr 2017 Location: Milford, NH iTrader: (0)	Thanks for the replies guys.... Techwiz - I was thinking exactly what you posted and have since come across a rebuild kit that includes the voltage regulator and bearings for $58. I know I can replace it in place but I've already got a new alternator so I'm committed at this point. The problem is getting the old one out seems to be a bit of a jigsaw puzzle. I've removed the four mounting bolts but can't seem to wedge it out from in between the oil filter housing and the A/C compressor. I'll keep looking for tips or DIY. I haven't found anything as of yet. I'm planning on doing the OFHG at the same time so I might do that first to gain more access for alternator removal. Efthreeoh - Thanks, I checked out the DIY for the N52. It doesn't appear to be the same (I know the N54 is not the same mounting set up either). I'll post any insight I gain going through this process.
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