My naa tractor has broken hyd pump gear, and gear on rear of cam shaft,and gear on front of cam shaft and crank gear. I installed a used hyd pump that had a bad gear and I replace it. The pump is not locked up.I am wondering that the pump having a bad gear on it when I got that the pump might be seizing up when it gets hot. I don t want to replace all these gears and run the tractor and then this happens again.