Okay guys back with the serp belt questions

Okay guys back with the serp belt questions...

2007 335i n54 160k..

So I have been going back and forth with these probably for the last two weeks, ordering/ returning parts..

Upon start up the belt slips off the power steering pulley immediately and rips..

Everything is tight under this car I've checked and rechecked, I've ordered new tensioners and both up and lower idler pulleys.

What I've noticed upon start up is 2 Knock knocks before car start and boom belt is ripped (visual/sound)

I've read that that we are able to swap our motor mounts for the 335is motor mounts but does it matter the year.

I need my car back asap and I'm trying to find a solutions without taking it to the stealer ship...

has anyone else had any serp belt issues..

Up until the first time the belt ripped 2 weeks ago, I have an no issues..

I'm running out of options here...

%d comments
  • Also check alternator pulley clutch

  • Cars
  • Okay so my understanding on the Alt clutch, it's supposed to spend freely when noting is stopping it, but once you block fan, clutch is only supposed to spin 1 way right?

  • Pulley on alt moves in one direction only, regardless of anything else. If it free spins both ways, it's bad.

  • Then that's my problem... my alt Pulley free spins in both directions...

  • Wait, I thought an alt was supposed to freespin either way tho if there's no tension on them..

  • If you find equal free spin, it's bad

  • Ooo okay I understand what you are saying now... my alternator spins freely without restriction, I've i stick something in it to stop motion it does not slip..

  • Right, but it also can't spin in reverse. If it spins both ways with the screwdriver between the fins, it's a bad clutch

  • Ya it doesn't spin at all

  • Either way?

  • No sir, only with the screw driver out

  • It has to spin forwards but not backwards with the driver inside. Your clutch is seized if it isn't spinning forwards

  • Cars
  • It's kinda normal. Most likely from heat failure. Cheaper to buy the clutch pulley and bring it to a alt/batt shop and have them replace it instead of buying the tool. The tool is cheap but it's rare to use. If you have someone local that's VA busy with one then you can do that too. You're going to have to remove the alt for ease though. You can do it on the motor bit is not that bad to remove either way