Good day. Last year I bought a 790 with FEL and Backhoe with 147 hours on it. I tried to use the FEL and it jerked quite a bit. After research (thanks to this site) I changed all the fluids and cleaned the screen filter. It worked great for the last few hours I used it. I recently tried to use it and again, it's jerking like crazy. My reseach seems to indicate either a clogged fitting, bad oil, air in the system (rubber hose leak) or a dirty filter (screen). My question is, can I remove the screen filter without losing all the hydraulic oil? Anyone know what rubber hose may be the culprit? Thanks for all your help, much appreciated.