So far this harvest, soil conditions have been wet across the midwest, but crops have been relatively dry. I haven't heard of a lot of problems with plugging combines, but if a combine refuses to ingest, or expel what it's fed, here are a few tricks to get things unplugged.
First, if a machine's warning lights come on indicating its feederhouse, cylinder/rotor, discharge beater or straw chopper is plugged, DON'T TRY TO RAM THE PLUG THROUGH BY STOPPING THE MACHINE THEN ENGAGING THE MACHINE AT FULL THROTTLE. Resist that temptation--it will only make things worse. At the first sign of a plug, calmly decide how to remove the load from the plugged component. If the feederhouse is plugged, try reversing the feederhouse if that's an option with your machine. If a cylinder or rotor is jammed, OPEN the concave ALL THE WAY. If the discharge beater is plugged, raise the chopper, disengage the rotor and do what you can so no more material is fed into the plug, and there's nothing preventing that plug from easily exiting if it starts to move. With everything reversed or open as possible, briefly engage the machine at idle. If nothing moves, give up. Only if there is slight movement of the plug should you go to full throttle. Slamming it at full throttle just wedges things tighter and makes the next steps more difficult. (But, I've been in your shoes, I understand your frustration, and understand that you WILL probably try ramming it at full throttle at least once. It's almost impossible to resist the temptation. So go ahead, jam it in there even tighter, and then move on to the next step.)
If the plug refuses to budge, there are options. All the options are easier if you didn't try to unplug it at full throttle, but...we've already discussed that.
One option is to manually dig out the plug. Remember to re-open the concave and loosen things to make manual unplugging easier. Many of you are unfortunately familiar with this strategy, and know that leather gloves, a hay hook, pry bars, crow bars and pocketknives are essential tools. Some guys carry hooked "linoleum knives" to help with unplugging.
A lot of my customers now use battery-powered reciprocating saws, aka, "a Sawzall" to cut tightly packed stems and stalks. Short, stiff blades can gnaw through tough stems, release pressure, and make manual unplugging easier. Don't forget the leather gloves.
There are aftermarket and OEM add-ons that attach to cylinder drives, discharge beater drives, and other commonly plugged components that provide slots or pegs so you can use a 6-foot railroad bar to rotate that drive sheave. It's best to install these before a plug develops, but some customers say they make unplugging much easier.
Finally, there are all sorts of tales of using 4WD drive pickups, tractors and other motive means to literally pull on a plugged drive to move it enough to allow some of the material to be removed. There are risks associated with hooking a chain to a rasp bar cylinder, discharge beater bar or drive sheave and then pulling on it with a truck or tractor. Some guys say it works slick. I can't vouch for this particular tactic, but you're free to try it if it sounds like a good idea to you. If a machine is so plugged that it takes a truck or tractor to budge the wad of material, there's a good chance the extra horsepower will just cause damage by bending shafts, distorting metal surrounding the plugged area, or damaging the drive sheave.
Sometimes you just have to start digging, pulling, sweating and swearing.