By now, harvest is stored in the bin, and the combine is resting in the farm shed. What about center pivots? They’ll sit in the field exposed to winter’s worst elements until warmer weather brings next year’s crops. There’s no way to shield them from ice, snow and sleet. That’s why end- and beginning-of-season maintenance is so important.
"A little bit of prep planning goes a long way,” said Rodney Flowers, Kansas branch manager at Nebraska Irrigation. That planning should include two center pivot inspections: one after harvest, another before planting. Post-harvest, Flowers recommends looking the machines over closely and documenting any faults. That way, springtime maintenance can focus on repairs.
“Everything is already on your piece of paper so there shouldn't be anything new to you,” he continued. “If you don't do it, you're going to do the entire job in the spring, and springtime is already hectic. By having the inspection in the fall, [half the job is done], because trying to do the inspection and a fix all at the same time is just too much."
Fall maintenance
After parking the pivot in the combine’s over-winter location sometime in autumn, Flowers recommends doing a thorough and methodical inspection of all its components. Avoid installing anything in the fall — wait until the spring. Instead, document everything carefully in a designated logbook.
"Name your fields, name your systems,” he said. "If you are a farmer and you have corn, you [document] what variety it is and population. … Why don't you go ahead and do the same thing for pivots?”
- Thorough maintenance checks should include the following:
- Check drains at every span to ensure proper drainage.
- Pull the sand traps.
- Flush the system to remove dirt and debris.
- Reinstall sand traps after flushing.
- Check all electrical components.
- Inspect for critter damage or intrusion.
- Check gasket seals on connections.
- Look for ant or larva infestations.
- Evaluate sprinkler condition.
- Assess regulator age (recommended to replace every five years).
Next, drain the gearbox and center drives to prevent icing. If around two teaspoons drain out, that’s normal condensation. If it’s a cup or more, a seal is probably out of commission. Write it down and move on to check the tire pressure and inspect for damage.
With everything documented, Flowers suggests buying necessary replacement center pivot parts and stocking up on oft-needed components during fall and winter sales. This lets farmers shop around for the best prices instead of being forced to purchase whatever is on hand at the last minute.
Regulators, gearboxes, tires, center drives, micro switches and fuses are several items Flowers recommends having on hand in case something fails during the growing season. Keep inventory. He says center pivot installations should be avoided before the spring thaw, which is the most damaging natural element to center pivots.
"It's the freezing and the thawing that hurts the most. People think it's sun. Sun is sun. But 90% of the wear on your hose is freezing and thawing,” he says.
Spring maintenance
Working from the checklist made in the fall, center pivot repairs should be done in the spring. Plan inspections carefully to save as much travel time as possible. Time is money, so it’s important to limit back-and-forth trips from the farm shop or machinery store to the field and from pivot to pivot.
“It takes me 10 minutes to run to the shop; it takes me 45 minutes to run to the store. I have to pay whatever the price is,” Flowers says.
As before, record the center pivot’s condition and track during every installation. Drain the systems again. If any water comes out, the seals need to be replaced because, according to Flowers, “the system ain’t putting it in there. All you’re getting is from the snow during the winter. That’s a telling sign.”
Flowers says to refill the gearboxes with oil once they’ve been reinspected. Then flush the system again to remove rust, check the sand traps for debris and, starting slowly, run water until it’s clear. Then, after a final general inspection of electrical components and connections, the pivot is ready for the season.