Caution on JD 7000 planters!!!!

[JDseller]

I had a neighbor that had just a terrible stand of corn last year. He brought his seed meters over for me to check and they where fine. Replaced the brushes even those weren"t that bad. Ran them on my test stand and they worked perfect. HE took them home and reinstalled them. We then ran the planter with two of the press wheel brackets held up in some soybean stubble. We did population counts and they where coming up about 30% low. We spent all day yesterday checking the drives out. I even went and removed two meters from my own planter. Still we where getting low population counts. Even worst was the fact that we where getting skips and doubles. He had not worked some of his last years corn ground and we check the population/spacing and saw the exact same problem. So the planter was repeating the problem.

Finally he was driving and sped the ground speed up way too fast. I could hear a clicking sound. Found the problem. The drive chain that comes off of the clutch had the tensioner sticking. It would tightening the chain real slow. When you stopped the chain would be tight. At planting speeds it would get loose and then the chain would loop and jump several teeth. That would jerk the units causing them to skip and drop a pile of corn. At regular planting speed (4 1/2 mph) you could not see it or hear it. I have had this happen with rusty/stiff chains. His chains where all new and lubed well. We removed the tightener and cleaned/freed it up. Reinstalled it and our populations where spot on. He had two hundred acres of bad population corn last year that was caused by a sticking tightener.

So I have been working on these planters since they where new in 1973. I did not think that I could get stumped on them any more. Well I was wrong. Old dog learned a new trick yesterday. LOL

 

[snoop-nc]

You might be an old dog, but you were able to correctly sniff out the problem when given the scent!!

 

[GordoSD]

DOesn't he have dual drive chains?

 

[Mike Aylward]

Good thing you caught it. It sounds like new chains on worn sprockets causing varying tension to me. Glad it worked out. Mike

 

[JDseller]

This was not the wheel drive chains. This is the chain the goes from the output side of the clutch to the seed transmission on the back side of the frame. Even up to 12 x 30 there is just one chain on the input side of the transmission. All four rows and all of the older planter have a slotted tightener on this chain. The later six row and up have a spring loaded tightener in this location. This planter was a 6 x 30 that was the last year before the 7200 came out. I am not sure if the slotted tightener was not better.

 

[David G]

I have seen the same issue on our 7000. I went through all the tighteners last winter and made sure they were free.