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Bushels per hour corn on a 740 with 8-30?

4K views 7 replies 5 participants last post by  lilboss1970 
#1 ·
Just curious how many bushels per hour are you all able to do with a 740 in corn with a 8 row head? I'm talking on the cebis what can you get the bushels per hour up to? I have been having some power issues with mine and I think we got it fixed, but last year I could run as fast as I wanted and this year it seems about 6 to 6.5mph is max now that its running right. I'm in 18% to 20% corn that's running around 200-250 bushel/acre. On the cebis it seems like around 3k is the max bushel per hour, is this about right? I'm running concave 24-27, 300-350 on cylinder speed, rotors 100 faster than cylinder, fan 1250-1350, chaffer and sieve at 18 and 14.

Also some of this corn is flooded corn, will the dirty corn pull a lot harder than the clean corn?

Thanks for any help.
 
#2 ·
I have the same setup as you with very similar settings and yield...thus year, lol.

I think I did about 3800bph on occasion, but didn't really push it in speed like you.

Dirty corn, and vehicle speed 6+mph require some good horsepower. I don't think you are exceeding your cleaning system, but I could see bring short on power because of the dirt and speed...mud/hills, then for sure.
 
#4 ·
What i have seen in Ohio especially with BPA like lilboss is limiting factor on a 740 is horsepower. With all models it is tailings return. I typically tail a lot with bottom sieve wide open to start and rotors as slow as I can get them. Every field seems different but I can usually get a better sample than the competition. If I see any rotor loss than i adjust my concaves and cylinder speed to eliminate this. Usually wider and faster than book. 6 mph in high BPA is too fast for any machine to do a good job no matter what color it is.
 
#6 ·
My issue in corn is getting corn threshed off the cob, especially a soft cob. I tried everything on some fields. I found 400 rpm and about 26mm did the best. One variety had a hard red cob and was super easy.

The problem I have with it not getting off the cob is the rotor loss never indicates a problem. The chopper sure doesn't have an issue taking care of it! This is with 90 sensitivity and concave filler plates and all roundbar.
 
#7 ·
I am running a 2014 740tt (so about 40 more hp then previous) and in 24% corn I was running around 4,200-4,800 bph. I had the cylinder around 330, concave 26, rotors at 430 ish, top sieve at 18-20 and bottom at 18.

All round bar and very very little loss.

I max out the cleaning system on side hills and have to slow down a bit in 24%+ but under that I rarely have issues even on side hills.

I still run out of hp unloading on the go especially in hills... 4 mph is 100%+ engine load.

This is with an 18r20" non chopping head in 240-260 bpa corn... This year lol.
 
#8 ·
I was able to get the bushels up to that 3500-3800bph in the good clean corn. I have hardly any tailings until I hit the flooded areas that have some burrs in it, then I just shut my top sieve down to run them out. The funny thing is my sieve loss moniter doesn't show any more losses with the top sieve closed down to the 11mm area.
I am running my sensitivity on 40 on both sieve and rotors. I hardly show any rotor loss, and my sieve is usually running around 5-6 bars. I have got out and checked and my losses are around 1-3 kernals per sq ft. I will be glad to get in some corn that is clean to see how things go. I'm guessing the soft ground conditions are also taking some power away also. Last year the ground was like concrete and yields didn't avg as well, but we did have 200 bu corn in the better areas. I also know the dirty corn is pulling a lot harder now that I'm in corn that has both clean and flooded out stuff.
 
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