I started doing my timing belt change today, to say lightly I really dislike the tensioner, I dislike how it functions.

I did the gap to the 8mm it is suppose to be. Torqued the bolt a bit past spec and yet upon turning the engine 2 rotations the gap has enlarged to about 10 or 11mm.

Here is a pic, can you guys give me your input?

 

The thread below MAY help you explain it better than I could.

Timing belt tensioner loosening after running 10 minutes