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Rotor loss on 2388

21633 Views 35 Replies 13 Participants Last post by  kiwi
I had similar problem on 2188, i run afx rotor, but believe the only difference is in the front impeller. i run all cih rasp bars, nothing special. i finally like the setup of one small wire concave in front, followed by two large wire and key stock grates. There is so much mog that needs to get out of the rotor and with small wires, just can't in my opinion.
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The only advice I have is to slow your rotor some more, tighten the concaves some, and dont cut wheat any lower than you have to. Less MOG. We used to run 850-900 rotor speed and 1-2 concave opening. The faster you run the rotor the more will go out the back.
Well,.........if you change brands and get a machine that sends just as much out the back,..then what?
To me, the engine tach is the most useless guage in the cluster. The only time my machine sees the engine tach is at startup and thats only cause it is the default guage. I run the machine by the rotor tach. This is just my way of running, may not agree with most so... In standing crops, I run a specific cut height and a steady rotor rpm drop, then set the machine according to those inputs.

So, explained a lot, but I still dont know how you arrived at this loss being from the rotor? You mentioned the gorden bars helping with the sample and tailings, but referenced the monitor as the indicator of tailings volume. Is this how you are reading the rotor loss, by monitor?

If you have a little patients, I virtually guarranty your issue can be resolved and you will be happy with the machine. It just takes a little more input about what else you tryed and how you are coming to the conclusion it is rotor loss. It sounds like the machine is responding to changes as you mentioned the gordens, so IMO anyway, that means the issue is solvable.

Any lengthwise oriented rotor machine is, or can be, quite touchy with reguards to the concave settings and rotor speed settings. The cleaning system requires an evenly levelled load accross it, and about the only means to insure that, is with the concaves and speed in direct correlation with the amount and type of material going in.
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Hi. We cut similar crops in UK and can harvest 30tonne plus/hr with 5 grain/sq ft loss behind sieves. We run sw helical st large wire then st small wire and keystock grates concave 2/3 and rotor8/900

Monitor always shows rotor loss but grain is not on the floor. The sensor is at the back of grates so grain hitting it is not lost and I also think especially in wheat the nodes in the straw can fool the sensor so I dont take too much notice of it and keep checking what is really happening on the ground .

What are you thinking of replacing it with?

I am sure axial-flow will give lower loss than any walker machine in these high yeilding crops. Since we changed to axial when we bale straw we do not get rats and mice eating strings, no grain left to tempt them in.

The hybrid drum then rotor machines ,lexions CTS, do seem to perform well here but are in a different league both in performance and price
Hi There,
Have had a 2388 with specialty rotor for about 4 seasons now and constantly get rotor loss when doing winter sown feed wheat. Yields are approx 11tonne /ha and i chop all straw as we no-till.
Have tried everything to stop the rotor loss form changing vanes,to different rotor speed, put in keystock grates instead of slotted, this year put in Gorden rotor bars in threshing area,have 4 straight bars in seperation area plus 4 rice peg bars, but nothing stops rotor loss unless i slow down so that engine revs are about 2420 (static is 2500). Have done everthing one at a time but still no joy. The Gordon bars certainly helped with thresh, as i can open the bottom shoe and get no returns showing on monitor now because of that. Have also tried really fulling her up by bringing engine revs back to 2380 but still have rotor loss probably worse. Getting to the stage thinking of changing combine as the problem is consuming me although i like the simplicity of the 2388.
Would anyone be able to express some ideas that might help ,thanks in advance.???
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Thankyou all for your replies. Just to give you some more facts so you know how i run the machine.
I have found the best rotor speed is between 720 and 850 in wheat depending on conditions . Concave is always at 1 on the scale and when checked has about 1/4 in gap. fan about 1070 rpm.
Have checked all the sensors are working and always do ground inspection to set them ,the loss on the ground can be up to 15 grains per square foot.
Only use engine rpm indicator Doorknob because it correlates to lower loss on the monitor and hence the ground. It seems if the rotor gets full and the rotor speed drops the grain won't separate so well.
I thought it was because we have alot of straw going in the combine but yesterday i had a small amount of straw and just the same rotor loss.
I Have a neighbour who has 1480 with standard beater rotor and he does a beautiful job of his wheat and always has more seive loss than rotor loss whereas i am the other way round.
He has tried to help and had suggested vanes adjustment and the keystock grates instead of slotted.
i feel i have three options left:
1. Put standard rotor in
2. maybe try 4 more straight bars in the separation area
3. Go back to conventional New holland combine we had before with rotary seperator
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You don't say how wide you are cutting, but 15 grains per square foot doesn't seem like an excessive amount.
Ok, how far does the rotor speed drop? I ask because if it drops so far as the performance falls off that much, there may be a mechanical issue that needs addressed.

The standard rotor is a fine wheat rotor. I have been looking at used machines in the eastern oregon area lately and they all prettymuch run the standard rotor. They are grain machines.

So 15 kernals per foot, times 43,560= 653,400 kernals per acre if it were that dense over the whole area. Divide that by about 12,000 kernals per pound of wheat on average=54.45 pounds per acre loss. Is this check a ways to the side of the seperator? Or is it directly behind it? How wide is your header?
If I did things right, you are getting about 160bushel per acre,...? What happened when you ran the rotor up to about 900 rpm empty?

You should be able to run by the rotor tach just as you run by the engine. Take into consideration you run a chopper and add that to the drop. Without a chopper, I pull the rotor down about 60rpm from empty. Then I set the machine to that capacity. That way I have a really steady load on the whole machine all the time.
Does your 3288 have the wet clutch pto or the electric/hydraulic belt engager?
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i Know it doesn't sound a lot of loss and if i back off capacity it is a lot less about 7 grains per square ft but i suppose i am trying to be a perfectionist but still want capacity. Seem to average about 26 tonnes per hour unloading on the move but the combine feels like it has got lots more capacity that i am missing out on because of rotor loss.
doorknob thanks for the questions and i can't answer them all at the moment to be honest. The header has the wet clutch pto ingager . The header front is a 1020 22.5 ft. The grain is spread over width of header front. the rotor spead drop ----well i need to double check when i get going again but pretty sure if set at 900 rpm empty it will run about 860 but need to check that.
I know straw copping will have some effect but with engine running easily at 2420 i would have thought i should be able to run rpm done to 2390 without over loading it . I hear what you are saying and will check the totor speed draw down next time.
Thanks for your help. I have followed your adaptions to your combine with interest and thought you must have had similar problems at some stage Doorknob?
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I have found widest concave setting which still gives complete thrashing works best.

When it really works well is when most of chaff remains on straw and grain is removed by centrafugal force rather than rubbing action of rasp bar on concave as in walker combine.

Like clothes in a spin dryer the crop needs to spinning and loose to allow the water/grain out.

Sounds to me with that rotor speed and concave setting and the volume of straw I imagine you have you are squashing it into a tight mat which is causing the loss.

Helical concave has allowed us to run concave at least one number wider .
I agree with homefarm. concave setting is pretty tight. If you are not having problems threshing I would open until you start to see unthreshed heads then tighten it just a smidge. good luck
I'm going to loosely throw about 10-20 rpm extra drop for the chopper. So IF, and I understand you are going to re-check your numbers first, but IF my machine is loaded at about 60 rpm without a chopper, then you should be able to run about 70 rpm or so drop. You should have plenty power in a 2388 for that, and, if your rotor drive is in good mechanical shape, you should be able to really move along.

Every concave design has a different opening setting that is proper. The deeper the wires are below the crossbar, the closer you have to run the concave to keep it from plugging.

As you've probably already guessed, I dont trust electronics very much. I have'nt figured how the rotor loss pickups consider it a loss when the pickups are still inside the machine and the grain that hits them goes down to the chaffer.
....*shrug* I also cant trust them when those rubber paddles are used on the conveyor augers. Those things fling a lot of grain around and some can hit the monitor pickups. The late model 2388s had the left conveyor auger replaced with a left hand flighted auger. I'll try to post a pic and see if I can explain my thought a little better.

So if you look a the paddle, you can see that as it comes around, it can catch grain coming from the grates and bounce it to the loss monitor pickups, which I think still work on density not velocity.

BTW, thanks for looking at my combine mods and not laughing too loud......
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Thankyou to all who have given there thoughts on my problem i very much appreciate it. i will get back to you shortly once some more harvest is done .Have about 50acres wheat to do and 35 barley before doing 60 acres linseed and 60 acres raddish. Our header combine looks just like in your picture Doorknob with the rubber paddle and left handed flight. Does that mean you have similar issues with your monitor and how much loss is acceptable to you.??
Will try opening the concave some more again but usually that has meant more white heads. But will give anything a try.
today i have taken every other wire out of the third fine wire concave, second section, for half of it. And then put cover plate in the front section of the first concave to make sure of thresh ,given i have taken some wires out near the back .
Have you checked your pinch point of your rotor can't remember for sure but I think it should hit on the 8th bar. If this is out it can cause alot of loss. We have also found sometimes you need more centrifical force, with rotor speeds above 1000 rpm monitor is me on my hands and knees. I do a lot of quick kills to get a better idea of where the machine may have an issue. Yield monitors are fairly well designed now days, but loss monitors....I still dont trust them.

I have the machine setup well enough now that I dont run any paddles.

I used to try for every kernal. Eventually I come to the conclusion that that is impossible. So I started looking at the rest of the farm and what is accepted as "loss". Stuff like crop mortality percentage, and spray volatilization, or wheel slippage with a tractor, etc. I will operate at a loss somewhat directly correlated to the weather I'm running in and the condition of the crop. The higher the yield, the higher the accepted loss. 15 kernals per foot, though not so far out of line that I would quit running if the weather was pushing, is a little high for a 22' head in good operating conditions.

I think you'll like the cover plate and the removal of the wires on the rear of the concave. I also like running a few spikes on the rotor along with the gordens, as you do. I removed the straight bean bars some time back. Now that I run helicals, I dont think I'll ever put them back in.
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Sounds like everyone has had the same problem with their case combines in wheat. The first year we cut wheat with our axial flow we wanted to sell it. We went through and put in three cover plates on the front half of the rotor, put in two rows of spiked bars in the separating area to help bust up the straw, closed the rotor until it touched the concaves then backed it up a bit. We run the rotor at 1000 rpms empty and try to keep it around 950 loaded. We leave the cleaning fan running at 1260 rpm's for all crops. We run a 1666 with a 20' header, usually run around 3-3.5 mph in wheat not keeping the straw. We did some work on the cleaning system as well. I think case makes an air deflector that you can put in just after your cleaning fan to help get more air to the back of the sieves. I don't know exactly what or loss is. Every time I stop and look for loss, I am looking for a long time. The heads are completely stripped clean. I would say we are somewhere in the area of 5-10 seeds per sq. ft. usually on the lower end. You should be able to haul a** with a22.5' header on your 2388. Just basing that on what I've seen with our 1666.
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Try this. I found it on the net.

Brent Lee Johnson harvests crops across the High Plains with eight 2388 Case IH combines. We reached him in his crew-cab Ford pickup while he was moving machines from Colorado to South Dakota.

Johnson says the biggest mistake farmers make is not getting their equipment set up right. “Farmers have a tendency to over-modify their combines,” he says. “There are so many products available and different ways to set up a machine. And some of the aftermarket equipment doesn't match the opportunities available on newer machines engineered by companies.” One example is the wrong combination of aftermarket sieves and concaves. You should check with your combine technician at your local dealer to find out what combinations work.

The next biggest mistake Johnson sees is the failure to organize grain carts and trucks efficiently. “Simple things like pointing the truck out of the field rather than having to turn a full truck in the field,” he says. “We do it as second nature because of the months and years of doing it.”

Johnson says you should always face your trucks away from the field to save time and wear and tear on the trucks and to give the grain cart easier access to them. You also should park trucks in a row and load the first truck first so you always know which way to go and never have to back up.

“We always station everything in the field so you don't have to back up and risk damage from unnecessary backing,” he says.

Finally, he advises, to save cart time, you should unload the combine in the grain carts as you are headed toward the truck.

A tip related to efficiency is safety. “The two work well together,” he says. Safety in his business means getting the word “hurry” out of everyone's vocabulary, he says. “I've never seen a crop that didn't get taken off the field. But I've sure seen cases where we had to bury someone when there was still a crop in the field.”

Johnson recommends that you do not set the pace of harvest at a frantic level. Farmers who enlist the help of family members or people in town should pace their workers according to their abilities so that they don't feel rushed and make mistakes. “For example, make sure you walk through the details of how to get the truck out of the field or how to unload it at the elevator or at the bin site,” he explains. “And just calm down.”

Johnson says if you keep a calm and positive attitude, you will get more work out of your people in a much safer environment.

Lawrence Dees Dees Seed Company Blountstown, FL
Crew: six

Equipment: three Massey Ferguson 9690 combines

Crops: corn, soybeans, oats, wheat, millet, clover, grass seed and rye

Territory: 11,500 acres in Georgia, Alabama and Florida

Lawrence Dees' accent is thicker than Alabama swamp grass. He custom harvests everything from corn to bahai grass seed as far south as Florida. We reached him at 6:30 a.m over a breakfast of grits to get his tips for corn and soybean farmers.

“Just be conscientious in your work is the only thing I could tell you,” he says. “If you don't, you'll waste a man's crop.”

Conscientiousness to Dees means walking the field behind every machine each time it starts to make sure crop isn't being lost. “We'll lose some, which is intolerance,” he says. “But we try not to lose as much as our competitors lose.”

He attributes his edge to two things: his Massey Ferguson 9690 combines and the few adjustments he makes to them. He says the Massey's rotary design lets him harvest a better-quality sample with less crop loss than with competitive combines.

“I wouldn't run anything else,” he says. “It is a whole lot simpler to operate. And with the helical vane feeder beater, high-profile chrome rasp bars, rotator knives, and constant speed rotor control, the machines will do a better job.”

He admits one exception is in wheat straw early in the season, where he says the John Deere conventional cylinder-type machine does a better job of producing straw that is to be baled.

Two adjustments Dees makes to his Masseys are to rotor speed and airflow. He follows the settings recommended in the operator's manual and then adjusts according to the crop and amount of foreign material in the sample.

“For example, in corn the book calls for an airflow of 1,100 or 1,200 rpm and a rotor speed of 500 to 600 rpm,” he explains. “If the cob is breaking up, then your rotor speed is too fast. If it is not shelling it all off, then your rotor speed is too slow.”

He says the amount of moisture in corn will dictate your final setting. For example, in high-moisture corn, airflow will remain the same but rotor speed may have to be increased. “So if you were running at 550, you may have to increase it to 625,” he says.

He uses similar setting in soybeans. He says airflow is basically wide open. Rotor speed is around 500 rpm and adjusted to the amount of cracks in the sample. “If you're seeing cracks or splits, go slower,” he says.
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Firstly lets hope the blasted weather turns around for you so you can your grain in.

Secondly I guess, is harvesting in those conditions, I'd consider 10 grains a foot something to be proud of. Seperating grain from tough straw is one of the main issues driving new engineering.

Electric loss monitors and I just dont get along. There's just too much going on in the sensor pickups confined location for me to trust anything they say. That flap is a bandaid. The issue causing the need for it, can be fixed with a few settings and as you have done, installing the right bars for the crop.

Ok, the absolute best way to know what you are up against, is to do a quick kill. I know it is a tough thing to think about as it seems so abrupt on the machine, but really, in grain, it is not that bad. If you really just cant force yourself to do it, then if you have a helper, have them put out a few flags in areas that you notice the worst loss, for a reference for you to be able to walk up to and know what you are looking for on the ground. That way even if its raining, you can put on your rain gear and go to the field to study the loss pattern. If you notice a heavy spot across the width of the seperator, make note of the location of the heavy spot. Is in on the left or right, or in between? If the loss appears to be even, then removing that paddle should not be an issue. That is assuming the paddle is located just like the one in the picture. If it is located right down next to the flighting, then we may have to look at other issues.

The wheat will be easier to crack after a rain IMO.

I think your machine is probably doing a fine job in the crappy circumstances you have to work with in the rain. I know its tough to take even 15 minutes making an adjustment when you know the rain is coming any minute, but usually once you learn why you are going so slow, and can make an adjustment according to what you find that increases our productivity, you end up making up for the lost time x10. If you have a nut driver to remove that paddle, and have a place in the field that you are maybe going back and forth harvesting, you can wait till you tank is full to a repeatable spot before unloading, make note of the distance you travelled, then remove the paddle and repeat that distance without looking at the monitor. If you lost ground and gained grain, you are on the right track. If it went the other way,.........well, have'ta make some other fix'ns.
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Sorry, I got this far,....
Farmers have a tendency to over-modify their combines,” he says. “There are so many products available and different ways to set up a machine. And some of the aftermarket equipment doesn't match the opportunities available on newer machines engineered by companies.” One example is the wrong combination of aftermarket sieves and concaves. You should check with your combine technician at your local dealer to find out what combinations work.[/quote] and really, I could'nt force myself to read another word after that. People with those lines of think'n scare the heck out of me.
Have done some more harvest for 1.5 hrs today until weather stopped us. has been very frustrating harvest with 7 inches of rain just as the cereal was ready to on clay downs can only harvest if they have tracks on their combines.
managed to get slightly better speed out of header today but with loss of about 8 to 10 grains per sq ft . had engine rpm loaded down to 2400 and rotor speed empty was 830 and loaded down to 780. had some more broken grain than normal due to the cover plate on front concave but was able to back off concave a small amount. tried faster rotor but just increased rotor loss on monitor ,however didn't get time to check the ground with weather pressing. You may well be right about that rubber flap doorknob ,and i suppose the only way to check is to take it off for a few runs . But would i get build up of straw or chaff because of it.? I have checked the pinch point when i put in the gorden bars this year so that is good. I suppose like the rest of you i have to accept some rotor loss as normal but it is frustrating to see good grain on the ground.
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