I am a Fire Investigator, I am particularly interested in details of any John Deere Combine fires as follows: JD Models 9600's, 9610's,CTS's, Scenario: The "primary countershaft" which runs sideways thru the combine right behind the cab, there is a gear box on left end of the shaft, and a pulley on right end, the p.c. shaft runs thru a plastic tube. The tube is open at each end, chaff, dirt, dust etc. builds up inside the tube. Eventually, if the tube is not cleaned out, the build up inside the tube rubs on the shaft resulting in friction which ignites the built up material and surrounding plastic tube and results in fire. Information on this or similar scenarios would be appreciated.