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Hello everyone, I'm new to this forum.
I have a N5 that keeps me disappointed and need some help.
My N5 breaks up cobs really bad and it is impossible to maintain a half clean sample and I am positive its my cage.
The cage in it is blue in color and don't know the brand but it has steep pitch helical bars in it and they are worn a little.
I think the helicals are too steep for cobs because think the cobs are rolling over the helical and getting smashed between the helical and the rotor bars.
I do custom work on the side with this rig and the customers are not impressed.
Which parts can fix this problem?
I only use it in corn and soybeans and I put a airfoil chaffer in it and it did improve a little but the problem is still there.
Also in corn I run the rotor 330 rpm and the fan works best a 6.
Any info on which parts to install and tips would be much appreciated.
 

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I had my old n5 set up with the steep pitch threashing helical double stacked. Another option some are doing is put the steep channel helical in threashing side. Next is to make sure you have the four lineup helical installed that connect the thrashing to the separator side and I also double stacked them. If my memory is right the old p1 needed the cylinder run about 450rpms to keep from breaking up cobs. Concave clearance was a minimum of 3/4. If the cob is big I did run as much as 1 inch clearance. Take the helical out of the belly on separator side. You can try no reverse bars on cylinder as long as losses don't get to bad.
 

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Had same problem, we put a rotor in with only 4 bars on it and it helped. Have also cut wheat this way. I would try rotor speed about 250 to see it that helps.
 

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Slower rotor speed will break the cobs up more. Broken cobs can cause more loss over shoe and dirtier sample. Faster rotor reduces cob breakup but increases rotor loss. Get the cob breakage solved first then see how bad the rotor loss is. It will probably be acceptable. There is more that can be done to help if rotor loss is to bad. Another thing I forgot to say earlier was the fan should probably be run wide open if you are keeping the machine at full capacity.
 

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Very hard for anyone to give great advice on an N-5-6-7 machine, when we don't know exactly what kind of Processor you have. If it still has the old original design concave and rock door, that would be a good place to start for cob breakage. Set the front of the concave at one inch clearance. Lower the rear of the concave (using eyebolts at the rear arms) until it's flush with the welded cage brace at the back of the concave. Adjust the rock door for this concave setting. This will minimize cob breakage as much as possible for the old concave design. I never used any reverse bars. I also never used fast pitched helical bars in a P-1 Processor because of too much rotor loss, especially in corn. I always add two extra rows of helicals over the top of the rear feed chain inlet and make a better transition path from right to left. Gleaner had a kit for this transition area. The best corn samples come from the 1 5/8" deep tooth square tip corn chaffer with the front 8 rows independent from the rest of the louvers. Any other chaffer doesn't do as good of job of cleaning corn and that's a fact. If you aren't running to full capacity and maybe only have a four or six row head, slowing the engine down to 2400 RPM from 2600 RPM helps in better cleaning and less blow-over from the sieves. I've done this over the years in a downed corn situation where the ground speed was limited due to stalks not feeding well. Re-adjust air/rotor speeds if you slow down the engine top speed.
 

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Also, you'll never see a whole cob from a P-1 processor.....they are pretty much all broken up, you just need to try and minimize it as much as possible and the correct chaffer helps in the end.
 

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Wouldn't replacing the steep pitch helical on threshing side with low pitch cause a lot of over threshing and break the cobs up more? If the original poster is referring to steep all the way through then yes the steep pitch on separator side needs to come out but that wouldn't be what is causing cob breakup. Never seen a p1 without steep pitch on right side. I never had any problems getting mostly whole cobs out of the old n5 with most variety's I grow. Variety of corn can play a big role in if you can get whole cobs. I did have one variety with a white cob that I could never get whole cob. Finally quit growing it.
 

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Correct. Steep was always on the threshing side on P-1's. I've never used steep all the way thru and would not on a P-1. It's been so long since I've worked on one of those, I forgot to add changes to the concave to open it up for more separation. The old original design concave would totally plug with cob bits and had almost zero separation. I always cut out every other wire in the back 3 rows of the concave and immediately rotor losses were greatly diminished. Again, with this poster, I have no idea which concave is being used. More open for corn is needed regardless of what concave he has.
 

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on my old N5 most of the cobs were whole coming out. in poor corn i would have to run slower rotor speed, but in good corn i would run over 500, after i replaced all of my helicals it nearly took all of broken cobs out of bin. make sure you dong have a cage door loose, or a hole in the cage
 

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Reminds me of when the first time I ran our N6. Lots of small pieces of cob in the bin. After pulling much hair out, found a big hole in the grate in front of the discharge chute. Can't remember if you can see the grate on the discharge chute in front of the impeller. Something to check. After replace the piece, sample was a 100 times better. Still running it today.
 
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