Hello Miniacs,

I heard a loud crack come from what I believe to be my belt tensioner today. I was changing my knock sensor, servicing the super charger, and doing some other things while I was in there but at the beginning when I released the belt, the tensioner sounded like it cracked. The spring was expanded enough to cover both holes and there was a lot of resistance when I started. Since there wasn't much give initially, I gave it some elbow grease. That is when I heard the *CRACK*. After I heard the noise, I stopped compressing but the spring did not return to its original position. The top most hole is now completely visible and the belt seems loose, whereas it was completely covered prior to this and the belt was tight. Could it be that the spring is no longer properly functional and the spring was "stuck" in an expanded position, and I cracked the spring loose? I'm not even sure that makes sense. The noise was extremely concerning and the lack of tightness of the belt concerns me even more. My car has 85k miles on it, so it's likely I should replace the tensioner anyway but figured I'd see if anyone knows what I experienced.

Since I needed the extra slack to get the belt off, I finished compressing the tensioner, put the pin in, and proceeded with changing my knock sensor. I haven't put anything back together yet assuming that I'll likely have to change the tensioner.

Any help is appreciated. I can provide pictures if they will help.

 

When I bought my mini the shock absorber on the belt tensioner was shot. The bushings were bad and it was only attached at one end.

I bought a new tensioner and while trying to compress it to be able to get the pin in the hole, the tool slipped and it sprang free and broke the new tensioner. Didn't seem like it should've been able to break so easily. Maybe I got a bad one?

 

Seems like whatever the crack was, it probably came from the dampener. It pretty much moves freely now. Going to replace the whole assembly.