Might ought to take the driveshaft clutch apart to clean and adjust. If it's working it shouldn't shut the tractor off. I bought a Country Way tiller this year and found the clutch bolts bottomed and the clutch discs were all rusted to the hub. After I cleaned it and put it back together I turned the bolts one turn past flush with the lock nuts and it is plenty tight to drive my 6 foot tiller.