This article is in response to correspondence from two Alberta owners of Gleaner combines: Wayne from St. Paul and John from the Peace River country. They had specific questions, but both said they would appreciate hearing about my experiences with the entire combine.
This column is the first of two about the Gleaner.
Let’s start with overloading the returns in canola.
In talking to Wayne, I got the impression that he had tried everything. We had a problem that he maybe didn’t know about. The air from the fan that is supposed to blow the chaff out the back and let the grain fall onto the sieve will blow the entire mixture down onto the shoe. It will plug just about everything.
When this happens, it means two parts are assembled wrong.
The piece that forms part of the accelerator housing comes down to meet the piece that forms the top of the air chamber. They are both bent toward each other so that they meet vertically.
A row of bolts holds these two pieces together, which can be seen from the back end. Remove the bolts and switch the two pieces so that the one in front is now behind the other one. The parts book shows it right.
The lip from the air flow points down when this is set up wrong, which you can tell by the pattern it makes on the side of the combine just behind the opening.
A flame-shaped wear pattern should point straight back. It will point down to the shoe if it is wrong. All the combines were made like that for a couple of years.
Another common question was, “when should I change my accelerator rolls?” The book says when it is half the height of a new one, but that is not a hard and fast rule. In my experience, they should be changed when performance falls.
The grain and chaff mixture comes down past that blast of air at four times the speed of gravity, which is a carefully balanced relationship.
The wind will blow out some grain if the speed of the mixture comes down slower than this, and the natural response is to cut down on the wind. But now you don’t have the volume to lift the chaff off the shoe.
The mixture will slow down as soon as the rolls start to wear. You need to check this every week if you are picking up a light swath in a poor year, especially if you farm in abrasive soil.
The quickest way to tell if you need new rolls is if you have to continually decrease your wind because you are blowing grain out the back.
The fan is a vital part of this. The blades are scooped so that they draw air from around the housing toward its middle, creating a slightly pressurized drum.
To get air to flow from it, we put a cutoff bar close that draws air away from the drum and creates a partial vacuum. The pressurized air from inside the drum rushes out to fill the vacuum and it continues out, down the air chamber.
These cutoff bars must be perfectly straight and an even distance from the drum. This is important. The chock sometimes gets full of chaff from the stone door opening. It will distort the cutoff bar.
I would also like to talk about setting the combine in canola.
I don’t think canola is blown out. Rather, it is carried out in the trash. Our job is to break up the trash before it hits the shoe, which is the idea behind the accelerator rolls.
Canola is heavy and round so the wind should not blow it out. Open up your sieve and chaffer to at least one-quarter inch on the bottom and three-quarter inch on top.
You might plug everything, but do not give up. Leave that shoe alone for a while and play with the wind. You might be surprised how much wind it will take to get a clean sample. This combine model just loves canola.
John, we should look at the front of the combine because that’s the area Gleaner spent a lot of time and energy on.
There were several problems.
The material had a tendency to follow the auger around. The company found that the forming tool made a pronounced knurled finish on the flighting: a band of this type of finish down the whole length of the flighting right in the middle. It was rough enough to make the material follow it.
The company also found that the stripper bar was inadequate and added another stripper bar on the bottom of the table. There are instructions from the company on how to install this.
The feeder chain takes the grain up to the concave, which is adjusted in the back because it pivots on the front.
You can’t set a concave so it’s tighter in front than the middle because it produces white caps.
The book provides settings that are allowed for this concave. Just ensure that you always have a positive wedge.