I have been trying to adjust the PTO clutch on my 57 620. Clutch was slipping some when hooked to my tiller. I have moved the cam as far as I dare since the holding screw is about off the slot. I now have two lands and two grooves when the clutch is engaged. However, when I disengage and check there is one land showing and according to the tech book that is not quite enough. Is there another way to adjust that I am now aware of? Any suggestions would be appreciated. I have not tried running it yet so not sure if I solved slipping or not. I only use this pto a couple of times a year to till my garden so It doesn't have to be perfect. I am sure it probably needs a whole clutch rebuild but I am not sure I want to spend that money right now. Thanks