E30 Timing belt whine after replacement Help needed!

[Blau320i]

Hello!

this is my first post on the forums so I'm hoping somebody might be able to lend a hand , I recently did a timing belt and water pump change on my 320i (we also replaced the spring and guide pin on the tensioner) , now as far as I can tell ever since I had the belt done it has had a whine which appears whenever I rev the engine
at first I thought it was my fan clutch but after removing the accessory belt the noise remained , it sounds like when a viscous fan is on full lock I will link a video of the noise so you can hear it for yourselves , now as far as I know we did the procedure correctly for tensioning the belt ,
we fully compressed the spring on the tensioner , set TDC and fitted the new belt , released the two 13mms and the spring set itself against the tensioner , locked the tensioner down then spun the engine two full rotations then slacked off the tensioner nuts to see if there was any additional movement which there was not , then locked it down again , I did some digging online and some say that the noise will eventually go away , im not sure how true this is but I don't really drive the car much so I don't see that happening on its own

[82eye]

did you replace the tensioner or just the guide pin and spring? old tensioner might not like the new belt and / or a new tensioner either isn't quality or has it's own song.

[brianallen]

A couple of things I’d check before assuming the noise will disappear. Since it’s still there with the accessory belt removed, I’d focus on the timing belt, tensioner, and water pump. A belt that’s a little too tight can make that characteristic whine, especially as RPM increases.

Your tensioning procedure sounds reasonable, but I’d recheck the tension with the engine cold and make sure the belt is properly seated on all the sprockets. I’d also listen around the tensioner and water pump with a mechanic’s stethoscope if you have one. If the whine appeared immediately after the job, I wouldn’t just keep driving and hope it goes away—worth finding the cause first.