Combines HElP Threshing Problems on new 8780

On the left side of your rotor there is a cover plate that runs from front to back, make sure you have the one without any holes in it installed. There is a perforated one for corn, milo and soybeans and a solid one for wheat. We have an 8570 and have had good luck threshing in all crops. There is a dealer in Indiana that has a lot of experiance with MF rotors, Rudolph bros. 812 897 1720. ask for nathan or Glen. JK

Thanks for the reply.

hey bruce how do u like your 8780IJ did u get the XP or regularIJ do u likie how it performs on the crops u are doingIJ do u just run small grains through itIJ can u see good at night with itIJ we have an 8570 i would love to have an 8780 wouldn't care wether xp or not but the money just ain't there right now it looks like a good machine to me allen thanks

Allen, We bought the regular 8780 setup as a corn_grain machine. We've only run it for a few weeks, we have had some problems wheat. We have ran it in barely and canola and it works great in these crops. We run mostly small grains as well as corn and beans. We are waiting to see how it will turn out there. I can see better at night with this combine than any other one I have ran. We will know better at the end of year how satisfied we are with it. Bruce

I have found that most of the machines come out of the factory with the rotor and cage not set-up properly. You can index the machine and then after a few hours find that it is no longer indexed. The rotor cage tends to take a "set" after a few hours and then remains pretty stable. In addition, the concave indicator does not mean anything, it is only a "relative" indicator of the concave-to-rasp bar distance. I index the concave to the rotor so it is parallel and equal distance from front to rear and left to right with the concave drawn-up tight. These measurement positions are shown in the Operator's manual from about the 7th concave bar on the left side and the 8th bar down on the right side. By that I mean, I find the highest rasp bar and adjust the concave up until it just touches and then back it off to just clear. Then I remove the indicator plate and elongate the holes to allow a true Zero indication. Then when you pull the concave up in tough threshing conditions, it really is tight. Also, I run the cylinder as fast as I can until I get grain cracking and then back it down 20-50 rpm's or if straw damage is too great, then slow it down to get all of the heads threshed with the minimal straw damage necessary. I have also found that the 8780 often does not feed properly off of the head. This causes "wads" of material to go through the rotor. Sometimes you will hear the rumbling, and sometimes you will not. These wads carry the heads through the machine unthreshed. This can often be rectified by increasing the header auger speed about 8-15%. This allows smaller "bites" to be fed to the rotor and it then does a better job. We have found that opening the bottom sieve and closing down the top sieve, and turning up the fan speed is a better way to go. This allows more air to go through the top sieve and keep material suspended in the air better, thus increasing our capacity.

You might not be keeping the combine full. Try slowing rotar speed to 850-900. This keeps the material in the combine longer. I own an 8780, and I use 2 concave blanks and I recommend an air foil chaffer and windspeed about 750-800. I have found running rotar at maximum speed sometimes has the reverse effect; and remember, rotaries run best when they are full.

We run a 8560 and have same problem.The biggest help was on top of the concaves just above your 3-blanks is a bolted on grate.(ONlY TO BE USED IN CORN)A solid small grain plate gets bolted in it's place.Also a slower rotor speed and tighter concave does a better job of threashing.Don't give up on a great machine you can alway's go back to bigger headaches.