I have a 2000 X reg Octavia and the alternator seems to have given up the ghost, no battery light in the dash already changed the battery new calcium one on car. Checked with multimeter for charge when running voltage dropped after starting from 12.5 to 12.1.

I need to change it but do not know how. looks like I have to take the tensioner off first to get at alternator bolts. but very cluttered there.

Dream

If you look at the tensioner you'll see a square boss with a small hole in it, there's also a hole in the tensioners back plate. Put a spanner on the boss and remove the tension, insert a 5mm masonary drill bit into the hole and locate it in the hole in the backplate locking the tensioner open.

The masonary bit will bend and be scrap afterwards, do no use a steel / wood bit as it will shear.

If you look at the tensioner you'll see a square boss with a small hole in it, there's also a hole in the tensioners back plate. Put a spanner on the boss and remove the tension, insert a 5mm masonary drill bit into the hole and locate it in the hole in the backplate locking the tensioner open.

The masonary bit will bend and be scrap afterwards, do no use a steel / wood bit as it will shear.

Is OK I sused it our have changed the alternator and fixed the problem.

Cheers