Combines loading up grain on chaffer

What crops are you harvesting and what concaves and grates are you usingIJ Does your return auger ever plug up and slip the clutchIJ

All crops behave the same way, wheat, canola,barley, oats, flax. Yes, I have plugged the return auger twice in about 12 years. We have always set the combine well enough to get a good job done, I always think there can be improvements.

I doubt your problem is caused by an air under the seive problem, your problem is uneven seive loading. The problem in small grain is that most of the threshed grain comes out on the right side of the concaves and overloads the right side of the seives. If you look at the sheetmetal at the rear of the auger bed,you will see that the paint is all worn off on the right side and factory new on the left half,where almost no grain comes out to wear it. This uneven seive loading is not a problem with large seeds like soybean,corn or field pea, but a big problem with small seeds like wheat or flax. what has worked well for us on our 1480's is to install the large wire(pea concaves) and use Harvest brand concave cover plates to "adjust" the combine for smaller or larger seed threshing and to get even loading across the seives. We use 3 harvest brand cover plates for flax or wheat, 1 or 2 for barley or oats and 0 cover plates for soybean or field pea. We get a good thresh and even seive loading with the large wire concave_cover plate combo. You have to run the concave clearance tight with this setup. Kind of a rule of thumb is if the thresh is poor and seive is loaded on the right, add a cover plate. Overthreshed and loaded on the left,remove a cover plate. You can also fine tune this with concave clearance and rotor speed. This setup has worked very well for us, the cover plates install or remove in 10 min and we don't have the dirty job or changing concaves twice per season. If I remember right,3 cover plates cost $150 US

The concaves are the first three elements (come in small and large wire versions) and the grates are the back three elements (come in slotted or keystock styles). All of the crops you mention have pretty small grain size, so the slotted grates would be the way to go, and likely what you have. Make sure the bars that cover up the center of each slot are in place. With the standard rotor, I suspect that you can get these crops threshed pretty well (except maybe the canolaIJ). If you are getting a lot of light, fluffy material in the return that has been well threshed, I would not hesitate to spend the $ on the air deflector kit. That will likely make a HUGE difference. On the other hand, if the return has unthreshed crop in it, I would go with the cover plates to make the threshing more aggressive. We use the Gorden plates. Once you get most of the grain threshed on the first pass, you will probably need the air deflector to keep return volume down to a reasonable level, especially if you try to get a really clean sample. I see no reason not to cover up the hole in the top of the return cross auger, regardless of the other changes you make. Putting all of the return back into the rotor cage just has to help keep the load on the sieves even. I think you should take a really close look at the pinch point between the rotor and the concave. I've been told that having it at 7 o'clock is important, but I have not run a machine that was set at any other postion. It would make sense to me that this could be the root cause of your uneven sieve load.

Thanks guys thats excellent advice, sorry about the confusion, I do have the slotted grates and the bars are in. I am certain that I do not have the adjustable concave setup but I can get a kit.

We had the problem of grain going out on one side of the shoe also and we consulted our dealer. Two years ago he installed a ajustment system from a newer 2188 in our 1660, he had to remove the old system and weld backer nuts under the feeder houseing and above the seives at the rear of the rotor. Once installed we have had two years of seeding without green strips on our fields.We now check the pinch point every year before combineing . Hope this helps you.

Does rotor speed change and loading on the chafferIJ Sounds like your problem is probably too much clearance on the right hand side of the concaves giving an incorrect pinch point. It is well worth the money to install the adjustable right mount for the concaves. Also when you do be sure to first level the concaves before adjusting pinch point. You should have about 1" clearance on the right hand side of the concave with concaves in home position. This fixed the same problem on my 1680.