Combines 8570 on fire

Some general thoughts on fire: You need 3 things to have a fire: 1. fuel, 2. oxygen and 3. ignition temperature. In a combine you have lots of 1. fuel, and lots of air blowing around 2., so you have to find the source of 3. ignition temperature. Possible sources of ignition temperature: Friction (as in rubbing 2 sticks together) look for jamming, packing and winding of straw or chaff somewhere. Sparking (2 pieces of steel striking each other, or possible stones and steel) Bearings can also be the culprit. Spontaneous combustion (tightly wound oil rags is a good example) In the case of the combine it could be oily or greasy straw or chaff tightly packed somewhere that starts smoldering. Electrically generated heat: too much current through too small a wire (resistance) will cause it to heat up, as will poor contact resistance in an electrical connection. Shorts or intermittent contact can cause arcing. Check for frayed wire insulation as the wires rub against metal. Sorry I can't be more specific, but I hope I've pointed you in the right direction.

Well, on our case 1680 we have a problem only in one certain crop that happens to easily ignite. The spark comes off of the turbo turbine housing and blows onto an idler pulley where dust and chaff get caught. Then the burning dust get throne to a different location and starts to burn there. It took a while to find out exactly how the burning embers got to the spot where they could continue to burn without being disturbed. Even though we blow the engine and machine down with air, the dust is just sticky enough to catch on the turbine housing and then fly off once ignited. Fortunatly, the spot where it gets to burn is so small there isnt enough material to cause any damage. We just consider walking around the machine and checking for smoke every tankful a part of doing business.