Don't torch your combine - simple maintenance can greatly reduce your risk

University of Nebraska Medical Center
While fall fires can’t be totally eliminated, a few precautionary steps can greatly reduce the likelihood that fire will ignite inside in your combine or the field you’re harvesting.

Fire in a combine is the last thing farmers want to encounter during harvest.

While fall fires can’t be totally eliminated, a few precautionary steps can greatly reduce the likelihood that fire will ignite inside in your combine or the field you’re harvesting.

“As a 38-year volunteer firefighter and emergency medical technician, I know an uptick in fire calls occurs every fall,” John Wilson, retired University of Nebraska-Lincoln Extension educator, says. “If you didn’t get your combine thoroughly cleaned out after last year’s harvest, make sure you clean it before going to the field this year. One of the main causes of combine fires is accumulated residue that ignites when a combine belt or pulley heats up due to friction with crop residue. It takes time to do a thorough cleaning, but having a combine fire in the middle of harvest is about as bad as it gets.”

Depending on how much residue builds up in the combine during harvest, cleaning it periodically through harvest is also advisable.

Thorough maintenance should include adequate lubrication and greasing all grease zerks as it’s easy to miss one here and there. Inspecting wiring will help reveal any hazardous damage to wiring insulation that requires repair or replacement.

“Damaged wires can be an ignition source for dust or accumulated residue,” Wilson says. “Also, you don’t often see sparks coming from a combine exhaust. However, installing a spark arrestor on the combine exhaust system is an inexpensive step to prevent that hazard.”

Before it’s time to go to the field, it’s advisable to have two fire extinguishers in the combine. One should be in the cab. The other should be located in an area where it can be accessed from the ground. For extra fire insurance, carry a fire extinguisher in the semi cab or tractor cab used with the grain cart.

Before you need an extinguisher, inspect it to verify it’s been serviced and is ready to use. If your extinguisher needs servicing, it may be just as economical to replace it rather than service it.

Before fire breaks out, it’s also helpful to review the steps for using it to extinguish a flame.

“PASS is the acronym I learned when using an extinguisher,” Wilson says. “To use the extinguisher, pull the safety pin and aim it at the base of the fire. You don’t want to shoot over the top of the fire or in the middle of the flame. Aiming at the middle can cause flames to push outward and add to the flame rather than putting it out.”

After aiming the extinguisher at the base of the flame, squeeze the handle to discharge the contents. As it empties, sweep back and forth along the base of the fire. Pull, Aim, Squeeze and Sweep.

Fires that occur during refueling a combine are not common, but they do happen. Farmers shouldn’t hesitate to turn off the combine engine and give it about 15 minutes to cool before they start refilling it. This practice is easy to sidestep but doing so could result in great loss to equipment, crop and human life.

“Shutting off that engine is one of the key practices for avoiding a combine fire,” Wilson says. “Of course, if you smoke, don’t do it during refueling.”

Due to significant drought in 2020, many fields across the Midwest are seriously dry, setting the stage for fires during harvest.

“This year, it’s possible that heat from a catalytic converter on a vehicle could set grass on fire,” Wilson says. “Sparks of any kind right now could result in a major fire. The first step is to do a thorough job of cleaning and maintaining your combine. That will greatly reduce the potential for problems down the road.”