I have tried researching this, but it's surprisingly bare on the internet. I inherited this hammer from my dad when I bought his house. I had to adjust the clutch blocks. The wheel is a rear mount, and I've got it to where I push down on the treadle, it runs like it should, but when I let off, the hammer won't disengage. It'll slow down, but not disengage. When I kill power and cycle it by hand, the treadle works as it should (push down, engage...let off, disengage). I'm on the verge of just putting new clutch blocks in (current ones are plywood...not my idea), unless there's something easier or more obvious I'm missing.