You could be right there, we never changed the tape on the screen, could have made a big difference. As for our capacity problem I was just thinking maybe our paddles were out of time, I don,t know if that would affect much or not.
every season before i go to the field with my 860 I take air intake drum out competly and first blow out all dirt out of radiator fins and then if its not good enough take a presure washer and wash them out -- but be careful that you dont use so much pressure that it flattens fins on radiator, and every 3 years i take radiator out and take it to radiator shop and have them cook the inside cores clean,and I if the tape is good and the gasket on the air intake drum I never have a overheating problem--- another thing I do is while blowing out radiator with air is start the engine and let it idle--- it helps to get the dust and dirt out of the fins.