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Having lots of trouble with cylinder taking in crop.

I was told that the 3-rib belt on the right side could possibly be out of time.

How do you time the maching?

Has anyone heard this problem?

Everything will continue to turn except cylinder will come to a dead stop with very little material inside cylinder.

Thanks
 

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The timing that they are referring to is the variable speed belt. If I remember correctly, the 4420 still used the bicycle chain to control the upper and lower pulleys to set the cylinder speed. The design goes back to the 3300, 4400, 6600, & 7700 combines and worked ok when they were new. Your operators manual should have the procedure to check and adjust the timing of that drive.

On Dad's 7700 the chain would jump off occasionally, mostly due to vibrations, and the way he would put canola piles through the machine. Once the chain jumped off, the pulleys would go out of time and the belt would be loose and start slipping. The younger brother got real good at setting everything back up in a couple of minutes.

As long as all your 3 rib belt is running at the proper tension, it is pretty hard to make it slip. The old 7700 used a 3 rib belt also, and that one would last a long time compared to the variable belt. One thing we would do is use graphite on the screws, both top and bottom, so that they would adjust easier. Fastest way of adding graphite was to mix it with WD-40 and paint it on the screw threads. Made adjusting pretty easy.
 

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On some models, there was a shear bolt on the cylinder drive pulley. Not 100% sure which particular ones or serial number breaks had it, but check to see if the pulley on the cylinder shaft has a shear bolt in it. There will be 3 bolts 3/8" x 2-1/2" (#6 in picture) that hold the hub on the shaft and then there is a 1/4" by 2-3/4" shear bolt (#1 in picture).

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