Crank Pulley Wobble

cjet68 · 12-13-2021, 04:01 PM

I have a 2011 335i N55. Just replaced the tensioner, 2 pulleys and the belt. The squeal was better for a day or two but it has definitely returned.

Hope to hear back if anyone figured out what causes this. Thanks!!

whyzee125 · 12-13-2021, 07:13 PM

All the n55's unfortunately wobble. They are also known to fail so that very well could be the source of your sound. My friend did belts and pulleys, then the crank pulley balancer, then finally the fan which was the issue. Dead silent for about 300 miles til he spun a rod bearing at 72k lol

Esixty1 · 10-21-2022, 04:41 AM

Hi team, sorry to revive an old thread. Unfortunately the resolution for this was never posted. Anyway, on the subject, in trying to diagnose a noise/harmonic with my N55, I'll try spraying water on the belt (used to use candle wax back in the day) to see if the tone changes. But was also wondering if it possible to run the engine with the belt removed for a little bit? Obviously it's not going to charge but is the ecu going to freak out if I try that? TIA

At23 · 04-23-2023, 03:44 PM

Replying to see there was ever a solution. Same exact issue on my 2011 335i

Marlin · 06-29-2023, 10:32 PM

Bumping this. Trying to solve it as well. Going on 2 years with this issue and basically every part replaced.

12-13-2021, 04:01 PM	#23
cjet68 Enlisted Member 3 Rep 45 Posts Drives: 2019 M4CS, 2005 M3 Join Date: May 2011 Location: connecticut iTrader: (0)	same problem here! I have a 2011 335i N55. Just replaced the tensioner, 2 pulleys and the belt. The squeal was better for a day or two but it has definitely returned. Hope to hear back if anyone figured out what causes this. Thanks!!
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12-13-2021, 07:13 PM	#24
whyzee125 Brigadier General 1673 Rep 3,640 Posts Drives: Dinan stage 2 335i Join Date: Jul 2014 Location: Chattanooga Tn iTrader: (0)	All the n55's unfortunately wobble. They are also known to fail so that very well could be the source of your sound. My friend did belts and pulleys, then the crank pulley balancer, then finally the fan which was the issue. Dead silent for about 300 miles til he spun a rod bearing at 72k lol
	Appreciate 0 Quote

10-21-2022, 04:41 AM	#25
Esixty1 Enlisted Member 23 Rep 48 Posts Drives: 2008 E91 335i M-Sport Join Date: May 2014 Location: New Zealand iTrader: (0)	Hi team, sorry to revive an old thread. Unfortunately the resolution for this was never posted. Anyway, on the subject, in trying to diagnose a noise/harmonic with my N55, I'll try spraying water on the belt (used to use candle wax back in the day) to see if the tone changes. But was also wondering if it possible to run the engine with the belt removed for a little bit? Obviously it's not going to charge but is the ecu going to freak out if I try that? TIA
	Appreciate 0 Quote

04-23-2023, 03:44 PM	#26
At23 Registered 0 Rep 1 Posts Drives: BMW 335i Join Date: Apr 2023 Location: Ohio iTrader: (0)	Replying to see there was ever a solution. Same exact issue on my 2011 335i
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06-29-2023, 10:32 PM	#27
Marlin New Member 0 Rep 7 Posts Drives: 2011 BMW 135i - M-Sport/DCT/PS Join Date: Jan 2022 Location: Seattle iTrader: (0)	Bumping this. Trying to solve it as well. Going on 2 years with this issue and basically every part replaced.
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