I have a B7610 with a 4' King Kutter XB brush mower. I used it earlier this spring and engaged the PTO at idle and it seemed to engage fine ( a little mower shaking to get started but i believe that is normal ) When I used it yesterday and engaged the PTO at lower RPM's it stalled out the engine. I turned the tractor off and then checked to make sure the mower blades were able to be easily turned which they were. In the end I was able to get the mower going but i did have to up the RPM's to keep it from stalling. It did seem to run fine once i got it going. I am wondering if it is normal to have to engage at higher RPM's with a bush mower or if there is another underlying issue i may have to look into??