hi every one . we have a volvo ec480 bought it new now have 18000 hours on it never had any trouble with it . the stick cylinder .gub screw to lock the piston on the rod came out and scored the barrel . re barrel . took the pump of and replace bearings and relap . but now when you pull a control lever noting happen and then it jumps nearly full speed . you have no fine control of any funks ion. the machine hydraulics is also overheating .
Good day The thread suggests you may have some damage in the main valve since any debri from the cylinder would pass the valve befor getting to the filters. Sorry if that news is not good. Kind regards Uffex