the leeson tensioner works put better when it is uptensioned - thats what i have found. Because mine is down tensioned at the moment and keeps coming loose on big kicks and if i do the tensioner up really tight, it still moves, but slower and is then too tight to move by hand.
so i have mine loose-ish now and just have to push it down by hand, but requires no tools and takes about 2 seconds :- - it probably does help i have stripped the metal hander plate and my tensioner is held on by zip ties (Y)
anyhow will be getting a new chain in a couple of months and will go back to up tensioning, which is better.
mike