hwp said:My guess is that you have a tiller that is designed to be used with a Snapper tractor. I had a Snapper 1855 (identical to a Massey 1855) and one of the attachments was a tiller like you describe. The rear PTO on the Snapper tractor ran at about 1000 rpm so if you are trying to use it with a 540 rpm PTO, it will run too slow. Mine worked very well but I don't have rocks.
I've turned the input gearbox around so it's a 2:1 speed increaser rather than a 2:1 speed reducer. It ends up spinning the tine shaft at half of PTO speed, so I have a tine speed of 270 RPM and 412RPM. It'd probably be better for the equipment to find a 1:1 box but that costs money. I'm cheap. Heck, I'm currently using a PTO shaft on it that used to go to an auger that broke, and the shaft lay in the mud for 5 or so years. Cut both ends off, shortened it, cleaned it up, and rebuilt the one broken ujoint and I have a perfectly good shaft for $15 and some time and consumables. Plus it's fun to weld.