Just in the process of changing the belt and tensioner, when the new tensioner arrived it had a small O ring around the bolt. Is this there to hold it all together and removed before fitting or is it fitted and acts as a damper.

Thanks

 

Fit it all together including the ring

 

the o ring does a really important job.....it stops the big ends falling out!!!

only joking the only job it does is stop the washer falling off the back of the bolt, that is it and that is from subaru themselves