Combines Concave adjustments for 9600

[tj]

If the concave appears to be twisted, it will have likely been twised before it was installed. (this is not that uncommon)

 

[SawTooth]

tj I appreciate your reply and i know of the hexagon shaft your are refering but what i was trying to say is that when you put in the 3_16 drill bit between the cylinder bar and the concave on the right side only and tighten it until the arm ratchets is that this twists the concave as does the concave stop.I took measurements on the opposite side as i had the drill bit in when i had pressure against the bit and as soon as i back off the pressure on the arm but still plenty of pressure to hold the bit in place the measurements changed a lot because of relieving the pressure it took the twist out of the concave. I also know of the cast steel closeout you refer to and i will have to check and see if that is limiting the travel i want to get the rear of the concave tighter.Do you run the rear of the concave tighter and if so how much tighter is it than the frontIJ This is my first JD combine and maybe i am being too fussy on the adjustments im trying to make.I previously had Silver Seeders and had a book for them to try and get the most out of them by making lots of changes in the shoe shake and by shiming all the cylinder bars within .020 of each in regards to the concave.I know that sounds drastic but it sure helped when it came to harvesting Amidon wheat.Before adjusting all the bars i would have cracked grain and unthreshed heads at the same time. Thanx again and maybe i should quit trying to get things set the way i want them....the Deeres probably dont need all that to do a great job! (I hope). ST

 

[tj]

I try to set the rear of the concave about 1_8" to 3_16" away from the tallest cylinder bar for zero setting, and the front no more than 1_4" away, although I have been known to set a worn concave at about 1_2" in front and then pull the rear back up to 1_8" to force feed the shoe. If you ever do this, you need to reset your zero marker--I found out the hard way when I did this for a customer. I made a mark with a black magic marker which he knew about, but he forgot to tell his hispanic hired man (who probably didn't ever look over his right shoulder anyway). No serious damage, but a power shutdown and a nearly headlong dive off the cab platform ensued. His man got back on the combine, but after that virtually refused to touch the concave adjust. You're right about the concave twisting when the left side is against the bottom stop. I usually bring the concave against the stop and try to mark the indicator with a dab of red paint. When adjusting zero, I use 2 pieces of 3_16" keystock--one on each side. One thing you may notice after operation, is that the cylinder may take on a twist--it usually leads 1_4" to 1_2" on the left side. I don't know why this happens, and it doesn't seem to cause any problems, but that's why I learned to use 2 pieces of keystock--it's easier to see what you're doing. Hope all this helps.

 

[Dr_Deere]

If you don't have your problem figured out yet I hope this will help. The way I do it is to find the cyl. bar with the flat washers on the end, if you have changed bars just pick one out and mark the end with a marker, so you are always using the same bar. Start with the concave fully open, then bring it up, when it is properly adjusted you should just barely be able to slide the bit between the bar and concave. I usally start and do the top and bottom on the right side and then the left.