Whine after timing belt change M40

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nickjf20
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Sat May 15, 2021 6:45 pm

Hi all, completed a timing belt change on an M40B16 today
All went well but I've ended up with this whine, see video. Thinking it may be an overtightened cam belt?

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paultv
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Sun May 16, 2021 10:00 pm

I'd check two things...is the belt correctly centered...I had an instance where the belt was touching the alloy cover creating a whine....turned out to be a worn idler pully allowing the belt to wander ....

Also sounds a bit like a locked viscous fan....

My reference is only to my own M20 rather than M40.

Paul :-)
4th May 1990 325i Convertible.

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https://bmwe30cabriolet-wdm.blogspot.com/
twright
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Mon May 17, 2021 1:24 am

is the fan rubbing on the fan shroud?
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nickjf20
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Mon May 17, 2021 9:52 am

Noise remains after removing the fan/shroud and accessory belts.
Retensioned the belt twice as well, no real change.

One of the (new) idler pulleys looks slightly off centre so I've ordered another timing kit ... hopefully it's that.
Fourth time lucky eh? At least I can tear down the front end in 40 minutes now
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