On Alfa number 15
AO Platinum Member
Join Date: Dec 2005
Location: United Kingdom
The fixed tensioner is easy to change. Remove the aux belt by releasing the moving tensioner. Use a 15mm spanner and turn it anti-clockwise to release the tension.
You should be able to tell if the fixed tensioner is worn by spinning it, usually if they are noisy they will feel rough when spun.
To change it you need a 15mm recessed spanner. A 15mm socket on a ratchet won't fit due to the chassis leg being in the way.
As for the alternator bearings, I am sure you would need to remove the alternator which is a right royal pain in the arse, due to it being right at the back of the engine. I am pretty sure either the subframe or the inlet manifold needs to come off to allow you to get to it.
It is most likely the fixed tensioner though.
You will never be cool driving a Vauxhall.