help - aux belt tension

[Oil-burner]

I can't 100% remember how it goes tbh, been a while since I did one I know it was fiddley as f*ck to tension it tho.
You'll see when it has gone to its full extension, as I said there is a wear indicator on the auto adjuster so you'll see if its tight enough.
Iirc I got someone else to take the strain of the auto tensioner while I set the manual one in place, makes things a bit easier.