JD 45 Combine question and pictures

[Weldon K]

I posted recently regarding the amount of corn being cracked by the JD 45 combine that I bought and tried out for the first time. Some of you suggested that I increase the cylinder/concave clearance and reduce cylinder rpm. I did so and harvested some more corn. There is still a small amount of cracked kernels visible, perhaps nothing more than can be normally expected. Most cobs are whole now or broken in two pieces but not split/crushed as before. The operator manual says to set cylinder/clearance for corn at 1-1/4 inch at front and 5/8 at rear. I could only get 1 inch at front. Just above is a picture and text from manual showing how to get more spacing at the front of the concave. I assume that this adjustment can be made only by removing corn head, or is it possible with corn head attached? I am running cylinder at 386 rpm , down from 536 before. I could get another sprocket and reduce speed farther to 325 rpm. Would this be any advantage ? Corn is less than 12.5% moisture.
Also above are a few pictures of the combine and shelled corn in the tank.






 

[tomstractorsandtoys1]

If I remember right you can do it with the hear on.The first time I set my 45 up for small grain I forgot to raise this adjustment.We raised the head completly and opened the door and reached in to work on it.Make sure to put a stand or plenty of blocking under the head,you can not be to safe.With the dry corn you will get some cracking.Have you tried lowering the cyclinder speed?(I know it is a pain with having to change sprockets and chain length).Our 95 corn special has a vairable speed cyclinder(It is not perfect as in heavy corn the belt can slip,you learn to keep an eye on the cyclinder speed tach)I sometimes wish for the chain setup as we seldom ever change it anyway.If you are selling the corn they almost always find something to dock for.The corn in the bin looked clean.I bought my first 45 when I was 18,it had a 235 cornhead and no cab,paid $850 for it and done enough custom work to pay for it the first year.The second year I added a cab off a parts machine that we bought.I could match my Dads 3300 round for round.We now have two 95's and a 55.
 

[Weldon K]

As I stated, I reduced cylinder speed from 536 which the previous owner had it set, to 386 which is slowest it will go with the three standard sprockets that shipped with machine from factory. With an optional 16 tooth sprocket I could get 325 rpm. I'll see how much one cost, it should not be expensive as it is small. I could get three other sprockets , all much larger and get 312 and 286 rpm, but those large sprockets would be $$$$$ and or the little further reduction in speed , I doubt there being any advantage for the $$$$$.
 

[ASR-Farms]

Are old 45 had filler plates in the cylinder for when we did corn. Do you have them in yours?
 

[Weldon K]

Yes.
 

[casecollectorsc]

I would leave the cylinder speed where it is. This is a unusual year for dry corn and next year you will probably need to be in the 600 rpm range. Sample looks great considering 12.5% corn.
 

[JD Seller]

I would leave it be. You are combining 12% corn. So next year you will have 20% corn and have to undo whatever you change this year. You sample does not look bad at all.

IF you are getting mostly whole cobs then opening the concave more will not help you any. Slowing the cylinder down may help you. The reason I say 'may' is that 12% corn will crack with everything set perfect.

Unless you are doing hundreds of acres I would live with it for this year. In more normal moistures you would never need that real slow speed sprocket again.