Corn/Soybean Suggested Settings for Midrange Combines-88, 130, 140, 150, and Legacy Combines (Suggested Settings)

Below are some Corn and Soybean suggested starting settings for 88, 130, 140, 150 and Legacy Combines (1600,2100,2300,2500 models) These are great machines and are pretty forgiving in their settings!

Corn

Concaves: Large wire Concaves– No Wires pulled.

Grates: Keystock Bar Grates

Rotor configuration: For high volume corn, suggest 8 straight bars on the rear of the rotor over the grate area.

Vanes: Front vanes in the medium position. You can run the back vanes in the medium position, but if you are concerned with rotor loss, a alternate suggestion is to put the back 5 vanes in the slow position (by slow, we mean the vanes will be almost straight up and down). By having the back 5 vanes in slow position (along with the 8 straight bars on the back of the rotor), this will pretty much eliminate any chance of rotor loss in high yielding corn.

Rotor Speed: Baseline is 350 to 450 RPM. A lot of folks like 380 to 400 RPM. (If you slow the rotor in an effort to control rotor loss, It is suggested not to run less than 300 RPM.

Because at this low speed, you do put a lot of torque/load on the rotor belt.

Concave module Clearance: Depending on the vintage/model of the combine, this can be different. The new 88 series calls for 18 to 25 MM. Other models might say 3 to 5 on the indicator. The key thing is to run the thickness of a corncob at the pinch point. Running the clearance at the thickness of a corn cob will do two things:

  • It generally will allow the ears to roll through the machine rather than tumble (longer cobs out the back). If you get the clearance too wide, the ears will tumble, and then you will have a lot of broken cobs to deal with in the cleaning system.
  • Running the thickness of a cob will put a certain amount of “rub” pressure on the concaves which can help prevent plugging of the concaves in green leaf varieties It will provide a wiping action in order to keep the concave holes open and available for separation.

Front Section of Chaffer Sieve: Also known as the pre-sieve. Baseline setting is 1/4 inch with the long cleaning system. Maybe, just a touch more. A good rule of thumb is to run the front section of the sieve half of what you run the main section of the chaffer. If you ever get corn in the cleaning fan, the root cause is that the front section is too far open. If you have the front section too far open, you may let too much corn through right away and actually create a pile on the front half of the shoe sieve. You will than loss air flow to the top sieve-making the top sieve ineffective. You have a lot of sieve, use the rest of it.

Main Chaffer Sieve: Recommended sieve is the 1 5/8 inch corn slat sieve. A good baseline setting is 5/8 of a inch between the louver openings. (About 13 mm. The new 88 series uses millimeters in the cab readout.) If you like, you can run the very rear section the same, or just a little wider to prevent any sieve loss. You want the top sieve to do over 90% of the cleaning.

Shoe Sieve: Recommended sieve is a 1 5/8 inch closz slate sieve. Baseline setting is 1/2 of an inch. (About 10 mm. The new 88 series uses millimeters in the cab readout.) Keep a open attitude! Do not close too much because you will close air to the top sieve also. Note: If you have good quality dry corn and the cobs are staying whole out the back of the rotor, you may be able to use wider setting on the chaffer and the shoe.

Fan Speed: Baseline is 1100 rpm. A lot of folks will use 1150 rpm or higher. If you ever think you are blowing corn out of the sieve while running in the field. Double check your front section of the chaffer sieve. Too wide of a setting on the front top sieve can create a pile on the front of the shoe sieve blocking air in the front which will in turn create super high velocities of air at the rear of top and bottom sieve.

Chopper: Low Speed (always drop stationary knives for low speed. Never chop in low speed.) It is a good idea to run the chopper in low for corn. If you run in high, the cobs will bounce off the back inside hood of the combine back on the sieves. The stain of the big cobs bouncing on the sieve will wear out the wires and sections can break out prematurely.

Soybeans

Concaves: Large wire Concaves– No Wires pulled. Alternate note or tip: In hard thresh rubbery green pods, some folks like to put a small wire concave in number 1 position with large wire concaves in number 2 and 3 position. This can help clean up a hard thresh variety. (Remember, you need all large wire concaves for Corn.)

Grates: Keystock Bar Grates

Rotor configuration: We usually leave it that same as the corn configuration listed above. However, if you don’t have corn, you would not need the straight bars for soybeans.

Vanes: Front vanes in the medium position. The back 5 vanes can be left in the medium position, but an alternate suggestion for green vine stems is to put the back 5 vanes in the fast position (by fast, we mean the vanes will be at the flattest angle possible). By having the back 5 vanes in fast position, you will get the green stems out faster. You will also find that it takes less power and fuel. (It doesn’t take long to move the vanes, maybe 10 minutes once you know how to do it.)

Rotor Speed: Baseline is 550 to 650 RPM-sometimes even 700. In damp viney soybeans, an alternate method to finding the best rotor speed is too start out in the field with a empty grain tank. Start out at 550 rotor rpm. Keep bumping the rotor speed up 20 rpm at a time and looking back in the grain tank. Bump up the speed 20 rpm at a time until you see the soybean actually crack/split in the tank. Once you see them start to crack, look at the rotor speed and back it down 70 RPM. You have just found the sweet spot to run rotor speed without cracking the beans. It will take less power and you will have better fuel economy. Of course if the soybeans dry down during the day, you will reevaluate rotor speed.

Concave module Clearance: Depending on the vintage/model of the combine, this can be different. The new 88 series calls for 15 to 25 MM. Other models might say 3 to 4 on the indicator. If you were to visually look at the clearance, it would be about 3/4 of an inch at the pinch point.

Front Section of Chaffer Sieve: Also known as the pre-sieve. Baseline setting is 1/4 inch with the long cleaning system. A good rule of thumb is to run the front section of the sieve half of what you run the main section of the chaffer. If you ever get beans in the cleaning fan, the root cause is that the front section is too far open. If you have the front section too far open, you may let too many beans through right away, and actually create a pile on the front half of the shoe sieve. You will than loss air flow to the top sieve-making the top sieve ineffective. You have a lot of sieve, use the rest of it.

Main Chaffer Sieve: If you also combine corn, you probably will use the same 1 5/8 inch corn slat sieve. Long sieve systems call for baseline setting of 1/2 inch distance between the louver openings. (About 12 mm. The new 88 series uses millimeters in the cab readout.) The nice thing about the 1 5/8 corn slate sieve is that if you want to run a little tighter, the sieve almost will act as a hole sieve due to the long fingers and bigger openings. You want the top sieve to do over 90% of the cleaning. Note: Some folks will run a 1 5/8 closz type sieve. Just be aware of what sieve you have, as this can effect what setting to use.

Shoe Sieve: If you also combine corn, you probably will use the same 1 5/8 inch closz slate sieve. Baseline setting is 3/8 of an inch. (About 9 or 10 mm. The new 88 series uses millimeters in the cab readout.) Keep a open attitude! Do not close too much because you will close air to the top sieve also. Some folks will run a 1 1/8 shoe sieve which will also do a nice job cleaning the pods out.

Fan Speed: Baseline is 1050 to 1100 rpm. If you ever think you are blowing beans out of the sieve while running in the field. Double check your front section of the chaffer sieve. Too wide of a setting on the front top sieve can create a pile on the front of the shoe sieve blocking air in the front which will in turn create super high velocities of air at the rear of top and bottom sieve.

Chopper: High Speed with stationary knives engaged.