Tips for better combining

Reading Time: 4 minutes

Published: July 4, 2002

REGINA – Most combines waste grain because they are improperly adjusted

or maintained, says combine parts builder George Kuchar of Illinois.

“If there is grain in that field that doesn’t leave through the

combine’s hopper or is damaged, then that combine isn’t set properly,”

said the tall American.

After 11 years as a custom combiner and “many more before that” as a

North Dakota grain farmer, Kuchar began building and selling the

modifications he had developed for his own custom threshing equipment.

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But he said no modification will improve a combine’s performance unless

the machine is running correctly.

“There is no point to growing a crop only to damage it or leave it in

the field at harvest. It’s like feeding a pig to market weight only to

have it die the week before you were going to ship it.”

Kuchar told farmers attending his seminars on combine maintenance at

the Western Canada Farm Progress Show to evaluate their machines

beginning where the crop “first meets steel.

“It all begins at the sickle. If you didn’t cut it, you didn’t thresh

it. Whether it’s a combine header or a swather, you need a clean cut.”

Sickle timing

Time the sickle in the centre of the cutter head, not at the ends. Poor

cutting or shattering of grain from the heads will occur if the sickle

teeth are not aligned precisely with the cutter bar guards.

“Reel speed is critical to managing the sickle. … It should look from

the side like a giant wheel pulling the combine along. It should be

spinning just a little faster than the forward motion of the machine.

Lift it as high as is practical,” said Kuchar.

Table settings

Tables “should be set to smile at you,” meaning they should be set

lower at the middle where harvested material collects.

Feeding the machine properly begins with the table auger. If the

material doesn’t enter the machine evenly, it overloads some areas of

the cylinder or rotor, or feeds one rotor more than the other.

“It doesn’t matter what type of machine you use, you need to take

advantage of the whole threshing mechanism to get any sort of capacity.”

Kuchar said the table auger should be adjusted to provide 2.5

centimetres of clearance at each end.

“Any tighter and you are pinching the crop material. It rolls, it binds

and fails to feed evenly. All you want to do is get it to the middle of

the table. Let the material that follows push it into the auger

fingers,” he said, demonstrating by pushing the air as if he was

rolling a ball away.

Table auger flighting should reach no more than about 7.5 cm into the

feeder house opening and must be in good condition. Auger fingers

should begin no closer than 45 cm from the end of that flighting.

“All flighting on a combine needs to have a flat, sharp edge. Table

augers are critical for this. Carry a portable grinder with you and

clean it up if it is damaged. When you see material flying up in the

table, this is often the cause …. Straighten any that are bent.

Hard-surface it if you can so you aren’t always spending time fixing it.

“It shouldn’t look like you’re rolling two big ropes up the feeder. You

want it spread across the cylinder evenly when it gets there.

Otherwise, you will not be threshing the grain in the middle of this

roll. And you’re chewing up the stuff on the outside and wasting half

of the cylinder’s threshing area,” he said.

Feeder housing chain

“Set the tension and clearance to manufacturer’s settings. Don’t try to

get fancy here and make sure it is the right way around. So many

machines have them in backwards. You can install them backwards, but

don’t. The crop will slip over the chain and if it is at all tough it

will plug the feeder. When it’s dry it pinches the material rather than

grabbing it and whisking it up to the thresher. You just need to get it

there,” he said.

The leading edge of the U-shaped feeder housing chain bars should be

the taller one.

Concave and cylinder settings

The harvested material should arrive at a concave and cylinder that is

“level and square with equal space on each side in the front … and

always feed the material into a wedge. If it’s a 1/4 of an inch in the

front, then make it a 1/16 at the back.

“When setting the concave, always find the high bar and use it to set

the front and the back, otherwise the grain will work its way to the

widest side and you lose efficiency.

“Canola is different from wheat, is different from corn. Set the

concave for the crop type.

“You need to feed that cylinder to capacity. If it’s running half

empty, then it won’t be doing a job of threshing. The grain is part of

the process.”

He said worn rub bars should be replaced, “no matter how many hours

they have on them. They are cheap relative to the grain you’re tossing

over the back end.”

Straw walkers

Check to make sure they are clean every time you fuel, he said.

Walkers should be clear of bearded heads, straw or corn cobs. Chopper

hammers should be sharp, otherwise they draw extra power and kick

material back onto the straw walkers.

Sieves

“Clean. Clean. Always clean. Air is best and keep any dust buildup out

of here, otherwise they can’t handle the grain.”

A build up of chaff in the sieves will prevent proper adjustment.

“If the spacing varies, the wind will be varied and some grain will be

going over the back end, some into clean grain and the rest into the

return so the machine can have another go at it. Clean grain should go

into clean grain. Nowhere else,” he said.

“Air is the easiest way to separate grain. The more air you can

handle, the cleaner your sample.”

He said if the sieves are set too narrow, the grain winds up being

continuously returned. This results in walker losses, damaged grain and

overloaded returns.

Bearings

“Don’t use a high pressure washer anywhere near a bearing; 3,000 pounds

of water pressure forced into a sealed bearing means that next week or

next month you are changing bearings. Lots of bearings.”

Kuchar recommends using compressed air and long wands for cleaning the

combine in the field.

“Save the high pressure water for the end of the season and then use it

carefully. If you had to take it to the dealer, tell him not to wash it

when he is done.”

Check all bearings, belts, chains, pulleys and sprockets prior to

harvest.

“If it’s worn, loose or in any way not nearly as good as new, fix it or

replace it.”

Monitors

Test all monitors, lighting and global positioning equipment on a few

acres of predictable crop near a home shop where adjustments and

repairs can be made easily and before harvest gets into full swing.

Modifications

“If you are doing everything else,then think about spending money on

after-market modifications. Until then it doesn’t pay,” he said.

About the author

Michael Raine

Managing Editor, Saskatoon newsroom

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