4th serpentine belt in 10 miles

[46m3csl]

So I already made a post but no luck.

I have changed the belt before on the car multiple times.

I had a squeaky belt and decided to change it with a new tensioner. Got everything on drove 10 miles belt shredded.

So bought a new belt and also got shredded within 5 miles.

Ok maybe I have bad brand new tensioner, bought a new one and same problem. From the first crank I see the belt has already misaligned on the pulleys and will come off.

I also check my power steering pumps bolts and snuggled them, also no contact with the subframe bushings.

Turns on the alternator clutch pulley was bad changed that as well.

So now do I go and change the idler pulley and the one additional pulley?


First crank I see a lot of movement at the tensioner but its on tight as it can go?


I done a belt and tensioner change on my 4 previous times and was pretty straight forward.

I need some help frustrated at this point

[gjm120]

Originally Posted by 46m3csl

So I already made a post but no luck.

I have changed the belt before on the car multiple times.

I had a squeaky belt and decided to change it with a new tensioner. Got everything on drove 10 miles belt shredded.

So bought a new belt and also got shredded within 5 miles.

Ok maybe I have bad brand new tensioner, bought a new one and same problem. From the first crank I see the belt has already misaligned on the pulleys and will come off.

I also check my power steering pumps bolts and snuggled them, also no contact with the subframe bushings.

Turns on the alternator clutch pulley was bad changed that as well.

So now do I go and change the idler pulley and the one additional pulley?


First crank I see a lot of movement at the tensioner but its on tight as it can go?


I done a belt and tensioner change on my 4 previous times and was pretty straight forward.

I need some help frustrated at this point

Are you sure that no belt material got sucked in the main seal?

Sorry I can't shed any light on why this is happening.

[olds350]

something is not spinning and causing the cuts to the belt. Time to make sure every pulley is free. check the AC and alternator as well

[JimD]

I agree that making sure everything spins is appropriate. If it does, I would check the pulley alignment. Your observation of mis-alignment of the belt also suggests something may not be lined up.

[dtla1]

There's gotta be something in there hitting the belt. Have you tried letting it idle and watching it instead of taking it for a drive? Maybe you missed a clip or screw on the radiator fan if you took that out and that's what it's hitting on?

[Rmtt]

Just a shot in the dark as I'm still learning these cars....but how does the AC pulley engage on these cars? Is it pulled in electronically via a clutch?

Maybe that could be frozen and not spinning freely when needed?

[Thunderguts]

I don't know how it is with the BMW AC clutch, but I've had two AC compressors fail on Hondas and you're left with no doubt. First you get the squeal, followed by a burnt rubber smell until finally the belt lets go. If it's a seized accessory, I think you would definitely know. Without those telltale signs, it sounds more like something cutting into it.

I would not drive the car again. Put another belt on it and get it to fail while you're watching (with protective eyewear). If nothing else, put a camera on it while you rev the engine and see what happens.

[Dackelone]

One of your pulleys is bent or wobbles. But which one. ?

Some forum members who drag raced or like doing burn outs with their cars... would get enough axle hop or had a torn/broken engine mount(s) that the engine's front crankshaft would contact the front sub frame damaging the crankshaft pulley.

Some people also experienced a belt breaking and then getting all wrapped around the crankshaft pulley and then getting sucked into the front crankshaft seal.


A belt laser tool like the one bellow might be needed to diagnose what's going on with your car. Maybe just using a cheap laser pen might also help ?

As far as the AC goes... when you remove the belt try spinning the AC compressor... it should spin freely. Also check all the other pulleys for a smooth spinning operation. You have to pull the radiator fan in order to replace all the tensioners - but I think you know that by now.

also these threads might help you... You are N55 right?

Replacing tensioning device for alternator drive belt (N55)
https://www.newtis.info/tisv2/a/en/e...ement/CyzmXfQq


and some other belt threads that might be helpful...

My Belt decides to rip and get caught in my radiator fan.
http://www.1addicts.com/forums/showthread.php?t=524591

Help! Shredded 4 serpentine belts in 100 miles.
http://www.1addicts.com/forums/showthread.php?t=1104374

Broken Serpentine Belt...
http://www.1addicts.com/forums/showthread.php?t=565322

Shredded serpentine belt
http://www.1addicts.com/forums/showthread.php?t=1063860


Good Luck,
Dackel

[MightyMouseTech]

Can also be the crank pulley itself. The pulley has a damper built in, which is a layer of rubber between the inner and outer portion. Sometimes that bond between the metal can fail, and the outer portion will no longer be firmly attached to the inner. Take a good look at the pulley.

[Mr Gasser]

When you finally sort through which pulley is crooked/AC clutch operational? you may want to install this:

Here is the link to get it, a must if you're a Horsepower freak:
https://www.oxwerkzperformance.com/c...eal-plate.html

[10"]

You did this yourself? Or a shop did it?

If you're doing this yourself; time to take it to a shop!

[gjm120]

Originally Posted by Mr Gasser

When you finally sort through which pulley is crooked/AC clutch operational? you may want to install this:

Here is the link to get it, a must if you're a Horsepower freak:
https://www.oxwerkzperformance.com/c...eal-plate.html

I saw that on E90 post.
If it is effective, it's worthwhile for not just hp freaks. Some people don't open up their hood until something goes wrong - like an ofhg leaking onto and causing a belt to shred.

[Mr Gasser]

Yeah, agreed.