How do you change hydraulic chuck on a okuma lathe?

To change a hydraulic chuck on an Okuma lathe, first ensure the machine is powered off and locked out for safety. Remove the existing chuck by loosening the hydraulic lines and unbolting the chuck from the spindle. Clean the spindle taper, then align and secure the new hydraulic chuck in place. Finally, reconnect the hydraulic lines and check for proper operation before resuming machining.