Combine Maintenance for Accurate Yield Monitor Calibrations
By: Brian Miller, Equipment & Precision Ag Sales
We all know that yield maps are the most important decision-making tool for next year, as well as the only way to verify results of the various tests you may have done throughout this growing season. This being said, we need quality data coming from the combine. To get this quality data, we need an accurate calibration coming from a properly maintained and adjusted combine. Let’s look at a few components that you can test before going to the field.
Clean Grain Elevator Chain
» This is a component of a yield monitoring system that often gets overlooked. The top sprocket should be in a fixed position that never moves for the life of the chain once it is originally set. It is very important that the clearance between the paddles and grain flow sensor stay very consistent.
» The bottom sprocket is the one that should be moved when the chain becomes too loose. A good rule of thumb is that you want the chain links to be able to slide from side-to-side on the sprocket, but not be able to pull the chain down more than ¼” at the bottom dead center of the sprocket.
Moisture Sensor Unload Auger
» Most combines have a small auger ran by an electric motor that pulls the grain away from the moisture sensor after it has taken its reading. If that auger was not cleaned out at the end of last season, the corn may have rotted, and the auger will not be able to turn. This will result in blowing fuses or needing to replace the electric motor.
Moisture Sensor
» This one is easy but still important. Remove the moisture sensor and make sure that it is clean. While there isn’t a great way to test the moisture sensor for accuracy (without running grain through the machine), on most monitors you can see the temperature reading of the sensor. This is a good way to make sure the moisture sensor functions.
Speed Sources
» Drive your combine around for a bit and check your speed sources for accuracy. Some yield monitors use more than one speed source, so be sure to check each one. The most popular speed sources are GPS and transmission speed sensors.
Header Height Sensor
» Raise and lower your feeder house and watch on your monitor to see if it indicates when the head is raised, and when it is lowered. You do not need to have a head attached to the combine to do this. If it does not change when it is supposed to, often a recalibration or a check over the mechanical components will fix your issue.