After my suspicions of the 1/4" x 1" bar interfering with the drive chain.....I took a closer look in operation today. Sure enough when the right side of the machine goes over a small bump.....it pushes that rod up against the sprocket hub and the chain. See the last of three pics below to see the interference situation. Not good!
I could see where I may lose another chain due to this situation......and not having a better remedy I decided to shorten the bar and placed a keeper bolt on the next lowest hole (so it does not get too short and disconnect - unlikely but possible). I cut the rod with my reciprocating saw and was back in operation in about 10 minutes. Grid power baby!!! I put a 4x4 block under the disk openers on the row unit so I could get my saw blade to reach the rod. Easy / Peasy.
I will need to buy a new bar as the one I have has a somewhat permanent "set" to it now. So does the bar on the oposite side of the drill.....but it does not affect any operation. Not sure how these bars get bent? (Mine came that way.....and I never noticed it until after I bought it.).
I cannot reposition the sprockets as there is not enough shaft to move the drive shaft on the seed box. I think I will call the engineers at Great Plains and talk with them. I wonder if they have changed this over the years......or if this same situation is present on other drills??
Something to be aware of if your having chain issues.
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