shredded belt

mattr135i · 07-17-2022, 11:58 PM

i'm not sure if anyone has went through this before but my serpentine belt shredded this morning while my car was warming up (luckily i turned the car off as soon as i heard it so no belt pieces went behind the crank pulley). I believe it might have something to do with my ac compressor failing but i could be wrong, last night when I was driving and turned on the ac i heard a vibration/almost grinding noise coming from the front side of the engine when I had the recirculation for the AC on. my assumption is that maybe the bearing in the compressor gave out this morning and caused it to seize up possibly causing the belt to shred ? ordering a new compressor tomorrow and hopefully that helps with the issue, this never happened before & there are no oil leaks on the engine so that is ruled out of the equation. also changed the powersteering pump pulley with an aluminum one & torqued the bolts w/ loctite so that isn't a possibility either. If anybody could give me feedback on this I would highly appreciate it!

Gangplank · 07-18-2022, 05:48 AM

Don't know about the compressor but the belt "walking" on the pulleys & tensioner is definitely a thing. Have you changed to tensioner as well?

zx10guy · 07-18-2022, 07:16 AM

If you did not have the A/C button activated or front defrost set, the A/C compressor should not have been running. The compressor pulley has an electrical clutch mechanism that engages when the DME requests A/C from the aforementioned situations. When the clutch engages, it engages the compressor pulley to spin the compressor. Otherwise the pulley should free spin. You can manually check this yourself now that the belt is off. Just spin the center/ribbed section of the compressor pulley and it should spin freely.

mattr135i · 07-19-2022, 05:02 AM

Quote:

Originally Posted by Gangplank

Don't know about the compressor but the belt "walking" on the pulleys & tensioner is definitely a thing. Have you changed to tensioner as well?

i did the tensioner & idler pulleys recently, they all are in great shape which confuses me. changed the powersteering pulley aswell, i did hear a squeaking before the belt ripped though.. no pulleys are loose and have been torqued previously aswell

mattr135i · 07-19-2022, 05:04 AM

Quote:

Originally Posted by zx10guy

If you did not have the A/C button activated or front defrost set, the A/C compressor should not have been running. The compressor pulley has an electrical clutch mechanism that engages when the DME requests A/C from the aforementioned situations. When the clutch engages, it engages the compressor pulley to spin the compressor. Otherwise the pulley should free spin. You can manually check this yourself now that the belt is off. Just spin the center/ribbed section of the compressor pulley and it should spin freely.

it does spin freely, there's very slight resistance with the pulley. it was making a vibration noise/squealing though before the belt snapped, make me believe my compressor's bearing was finally going

ErvGotti · 07-19-2022, 11:33 AM

Happened to my friends 335i N55, compressor somehow seized and shredded the belt. Though there was some squealing before the compressor seized.

mattr135i · 07-19-2022, 08:52 PM

Quote:

Originally Posted by ErvGotti

Happened to my friends 335i N55, compressor somehow seized and shredded the belt. Though there was some squealing before the compressor seized.

did replacing the compressor solve the issue? mine doesn't come in until friday unfortunately

ErvGotti · 07-20-2022, 09:58 AM

Quote:

Originally Posted by mattr135i

did replacing the compressor solve the issue? mine doesn't come in until friday unfortunately

Yes he was lucky also it didn't get sucked in through the crank pully. He replaced the compressor and all pullys, belts, and tensioner and it's been running strong for 2 years.

BlueBMWN54 · 11-07-2022, 10:02 AM

My belt shreaded luckly nothing in the crank seal but pieces everywhere even behind the idlers. So I was replacing the tensioner and all the idler pulleys I noticed that the upper idler was a 90mm instead of 80mm that was supplied in the kit from FCP. Since that pully was ok I left it which is probably why the belt was so tight. Any reason this was done other than someone at sometime had replaced it with the wrong one? thinking I should take it back apart and put the one that came in the kit on which would give the tentioner some more play

Mr Gasser · 11-13-2022, 09:26 AM

could be the clutch was working fine but the compressor was internally locking up causing the clutch to not spin...so a new A/C and belts should fix the problem.

Question: I need to do my belts since hearing all these disasters, what FCP kit has all this?

piotrek4000 · 11-25-2022, 12:36 AM

I had this happen on my car about 5 times before I finally figured it out: worn out engine mounts.

The engine would rock so much on the worn mounts, the power steering pump pulley would hit the subframe (low clearance to begin with). This would knock the belt off and shred it. I replaced all the pulleys and went through so many belts before I figured this one out, I would suggest you check. You can tell by looking at your power steering pump pulley, if there's a chip or dent in the pulley, that's your problem. Good luck!

07-17-2022, 11:58 PM	#1
mattr135i New Member 0 Rep 10 Posts Drives: 2008 BMW 135i Join Date: May 2022 Location: Hawaii iTrader: (0)	i'm not sure if anyone has went through this before but my serpentine belt shredded this morning while my car was warming up (luckily i turned the car off as soon as i heard it so no belt pieces went behind the crank pulley). I believe it might have something to do with my ac compressor failing but i could be wrong, last night when I was driving and turned on the ac i heard a vibration/almost grinding noise coming from the front side of the engine when I had the recirculation for the AC on. my assumption is that maybe the bearing in the compressor gave out this morning and caused it to seize up possibly causing the belt to shred ? ordering a new compressor tomorrow and hopefully that helps with the issue, this never happened before & there are no oil leaks on the engine so that is ruled out of the equation. also changed the powersteering pump pulley with an aluminum one & torqued the bolts w/ loctite so that isn't a possibility either. If anybody could give me feedback on this I would highly appreciate it!
	Appreciate 0 Tweet Quote

07-18-2022, 05:48 AM	#2
Gangplank Brigadier General 1575 Rep 3,076 Posts Drives: 2011 e82 135i n55 Sport w/ DCT Join Date: Nov 2015 Location: Vero Beach, FL iTrader: (2) Garage List 2011 135i [0.00]	Don't know about the compressor but the belt "walking" on the pulleys & tensioner is definitely a thing. Have you changed to tensioner as well? __________________ 2011 135i w/ DCT \| ZSP Sport Pkg \| PPK \| Ohlins R
	Appreciate 0 Quote

07-18-2022, 07:16 AM	#3
zx10guy Brigadier General 6303 Rep 3,636 Posts Drives: 2013 135i Join Date: Feb 2014 Location: DC iTrader: (0)	If you did not have the A/C button activated or front defrost set, the A/C compressor should not have been running. The compressor pulley has an electrical clutch mechanism that engages when the DME requests A/C from the aforementioned situations. When the clutch engages, it engages the compressor pulley to spin the compressor. Otherwise the pulley should free spin. You can manually check this yourself now that the belt is off. Just spin the center/ribbed section of the compressor pulley and it should spin freely.
	Appreciate 1 tracer bullet6189.00 Quote

07-19-2022, 11:33 AM	#6
ErvGotti Major 128 Rep 1,360 Posts Drives: 2008 135i 6MT Join Date: Jul 2010 Location: Aviano iTrader: (5) Garage List 2008 135i [6.00]	Happened to my friends 335i N55, compressor somehow seized and shredded the belt. Though there was some squealing before the compressor seized.
	Appreciate 0 Quote

11-07-2022, 10:02 AM	#9
BlueBMWN54 Registered 0 Rep 1 Posts Drives: bmw 335i Join Date: Nov 2022 Location: Pennsylvania iTrader: (0)	My belt shreaded luckly nothing in the crank seal but pieces everywhere even behind the idlers. So I was replacing the tensioner and all the idler pulleys I noticed that the upper idler was a 90mm instead of 80mm that was supplied in the kit from FCP. Since that pully was ok I left it which is probably why the belt was so tight. Any reason this was done other than someone at sometime had replaced it with the wrong one? thinking I should take it back apart and put the one that came in the kit on which would give the tentioner some more play
	Appreciate 0 Quote

11-13-2022, 09:26 AM	#10
Mr Gasser First Lieutenant 74 Rep 341 Posts Drives: 135i 09 M-Sport Black on Black Join Date: Jan 2016 Location: Texas iTrader: (0)	could be the clutch was working fine but the compressor was internally locking up causing the clutch to not spin...so a new A/C and belts should fix the problem. Question: I need to do my belts since hearing all these disasters, what FCP kit has all this? __________________ Metallic Black on Black 2009 135i, new waterpump, OFHGs, and VC gasket...RB turbo PCV valve (ooo), NGK performance plugs...V3Cobb access port stage 2+FMIC, Injen intake, Mishimoto clone FMIC, ARM charge pipe, ARM downpipes, Whiteline subframe bushings
	Appreciate 0 Quote

11-25-2022, 12:36 AM	#11
piotrek4000 Private 12 Rep 88 Posts Drives: 2009 135i 6-speed Join Date: Aug 2018 Location: Portland, OR iTrader: (1)	I had this happen on my car about 5 times before I finally figured it out: worn out engine mounts. The engine would rock so much on the worn mounts, the power steering pump pulley would hit the subframe (low clearance to begin with). This would knock the belt off and shred it. I replaced all the pulleys and went through so many belts before I figured this one out, I would suggest you check. You can tell by looking at your power steering pump pulley, if there's a chip or dent in the pulley, that's your problem. Good luck!
	Appreciate 0 Quote