JD turbo 7720 small grain: Can I combine corn with it?

bruceki

New User
So I picked up a JD 7720 at an auction at a pretty low price; it's been used in this area for picking up small high-value seed (chard, spinach, grass, etc). It was used with a swather and a draper head mostly, but sometimes with a direct-cut wheat head for some barley or wheat combining.

If I put a corn head on it, and adjust the belts and settings per the manual, is it possible that I could combine grain corn with it or are there too many other parts that need changed?

I've looked through the operators manual, and other than belts and settings, there's only one part that they mention as being different between grain and corn models. Corn models come with a finger bar (jd part #h37677) and grain models come with a beater grate (jd part #h37678)

I put in 20 acres of 90 day grain corn because the long-term forecast was for a warmer/drier year than usual. If I can't combine it I'll probably turn the hogs and cattle loose on it to harvest it.
 
You should have no problem 'converting' from small grain to corn.Change cylinder speeds,open sieves,adjust air.....Filler plates
are recomended,but are not required. It is however,imperative that you purchace an owners manual for BOTH combine and corn head.
 
check the concave wire spacing. it may have a small seed concave in it, because of the nature of the seeds it harvested before. if it does it won't let the grain out fast enough and you will get damaged grain other than that it should be fine like delta said
 
I did get an operators manual for the combine with the purchase. is there another manual I should aquire?

What part of the combine are the filler plates located, and what do they do?

I'm doing the filters/oils/grease thing right now. I've got 90 days until I could use it, so I have a bit of time to fiddle with it.

It is an old combine, but it's my first, and I'm actually looking forward to harvesting with it. Or spending the rest of my life fixing it. :)
 
Thank you. Are the concave wires difficult to replace? This grain is for my own use, so if it's a bit chewed up that's fine. the pigs won't notice - it'll be put in a hammermill anyway.
 
The filler plates go in the cylinder, between the rasp bars. Many on here do not use them; however, those that don't are usually harvesting lower moisture corn. The further north you live, the more likely you are to require them to do a complete job of threshing corn. In my neighborhood, WI, it would be unusual to find a combine without them.
 
The cornhead will have it's own seperate manual.The "filler plates" go on the cylinder.The cover the gap between the rasp bars.Theory is to prevent whole cobs/ears from getting into the inside of the cylinder.They are reomended,but not needed. If you get a set ,go ahead and install.If not dont worry.My 95 has never had filler plates,never been an issue....However,If you install filler plates,you MUST remove them for small grains as they can impede straw flow or even cause plug ups!...NOT fun! More importantly,they can fly off due to the faster cylinder speeds,resulting in a destroyed combine.The man who bought my 'old' 45 did not remove the plates when he changed over to grain from corn.A plate came off and destroyed a perfect older machine(bent concave;bent cylinder;twisted cylinder shaft;ripped/twisted off raspbars;holes punched in the side....) :(

he had only done one round. He had only bought it from me one week earlier.. :( But I wasnt blamed....Just one of those "s#!+ happens" kind of things
 
Another thing...About the beater. There are two kinds....My 95 was strictly a wheat/soybean machine.I'imported' it from south central KS to western Colorado(what a trip that was!).I simply installed a 443 corn head.Has the straight beater and straight(non stepped) strawwalkers,small grain sieves...Harvests corn as well as the neighbor's 95'corn special'.It does make a very clean sampleSo I dont really know if all that 'other stuff' really matters..And yesI ordered OMs on both combine and corn head.And a dealers parts book(yia Ebay).Really handy for ordering parts,I dont have to go 'argue' with the #@$&%* dealer!
 
If you're only doing 20 acres I wouldn't worry about the wires especially if you're going to feed it right away. When I replaced the concave in my combine seems like I took out every other wire to help with the damage and give it a little more capacity, It's easy to take wires out and put them back in when the concave is laying on a pallet, I'm not so sure how easy it'd be inside the machine. I still grind the corn a little but as long as the elevator doesn't dock me I'm not going to change anything.
 
In the upper midwest where most combines see corn at higher moisture, filler plates are in most machines. And with corn the most common crop, and small grains being "a little here and there," most guys don't remove cylinder plates to do small grains. Probably not right, but the way it is.

A lot varies by location...
 
Delta, those things make a difference when the corn is wet and the land hilly. All your corn doesn't get harvested until market moisture, right? Here it is common to do high moisture corn for cattle feed (25-30% moisture) and some seasons that's the shelling corn moisture, too.

Most anything will shell dry corn. My great grandfather used to take out the bottom spikes from his threshing machine and shell corn from the crib with that! I'm told it worked pretty well, too. Different climate, different tools required.
 
Steve, I will disagree with you (in a friendly way) about removing the filler plates for small grains. I used to own a 7720 and never removed the plates. I never had any trouble even with running the cylinder speed wide open. Idling the separator while it is engaged (but empty) will help with dirt collecting on one side of the cylinder. Once the filler plates are in the combine it's fine to just leave them there. Mike
 
Did you drive it? I drove mine home - about 30 miles - and it was a trip. My own little parade.
 
Just an update: Just finishing the last of my corn with the small-grains JD 7720. Had to replace the belt bearing in the feeder house, 4 of the drive belts, a couple of pieces of sheet metal under the house and it took a couple of hours of fiddling to get the concave and speeds right, but it's worked fine. I only planted 20 acres this year, and at the end I wish that I had planted a whole bunch more, because the combine sucks it up very quickly.

I went with a 443 4-row head because I can have the head on and drive it on the road, and it'll fit through the gates and access points for the field. The machine is basically not loaded with a 4-row header, but it's fine for the small quantities I'm doing, and not having to trailer it or make a second trip is nice.

thank you all for your input.



(quoted from post at 18:19:29 06/06/15) So I picked up a JD 7720 at an auction at a pretty low price; it's been used in this area for picking up small high-value seed (chard, spinach, grass, etc). It was used with a swather and a draper head mostly, but sometimes with a direct-cut wheat head for some barley or wheat combining.

If I put a corn head on it, and adjust the belts and settings per the manual, is it possible that I could combine grain corn with it or are there too many other parts that need changed?

I've looked through the operators manual, and other than belts and settings, there's only one part that they mention as being different between grain and corn models. Corn models come with a finger bar (jd part #h37677) and grain models come with a beater grate (jd part #h37678)

I put in 20 acres of 90 day grain corn because the long-term forecast was for a warmer/drier year than usual. If I can't combine it I'll probably turn the hogs and cattle loose on it to harvest it.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top