Some plunger-style moisture meters mounted in the upper clean grain elevator housing in grain tanks have plastic wear surfaces inside their plunger chamber. The right piece is a new chamber. The left piece is badly worn.
Check your combine components to reduce downtime at harvest
The folks at Case IH recently found a promotional film from the introduction of their Axial Flow combines in the late 1970s that bragged their machines could harvest an industry-leading 1,500 bushels of corn per hour.
"Today we’ve got lots of customers running 3,000 to 6,000 bushels per hour," says Kelly Kravig, CNH Product Marketing Manager. "Corn yields have increased, planting rates have increased. The amount of material we’re putting through combines today means customers have to stay on top of wear and maintenance to minimize power consumption and reduce down-time."
Kravig and other harvesting experts recommend farmers envision the flow of crop through a combine, from front to rear, to pinpoint areas of potential wear.
Feederhouse conveyor chains at the front of machines handle every stalk, stem, ear and pod of crop that moves through a combine. Jeff Gray, Product Coordinator, Claas/LEXION, says to "break" the conveyor chain at the master links and check each strand of those hard-working chains for wear before harvest.
"If you break the chain and remove a couple slats, it lets you wiggle each run of chain side to side and get a better idea of how much wear there is," says Gray. "It’s better to replace a worn feederhouse conveyor chain during maintenance than to dig a broken feederhouse chain out of the combine during harvest."
Threshing components are the heart of combines, and obviously subject to wear. All manufacturers offer wear-guidelines for rotor impellers, accelerator rolls, rasp bars and concaves.
"On Gleaners, you want to make sure the rubber on the accelerator rolls hasn’t worn down to bare metal," says John Keller, AGCO Production Performance Manager. "Helical bars, cylinder bars and components that handle a lot of material last longer if they have a chrome wear-layer. Once that chrome layer is worn away, they wear faster and performance deteriorates."
Worn components not only increase damaged grain and magnify losses out the rear of the machine, but increase power consumption and decrease bu./hr. capacity.
Keller cites clean grain conveying systems as an example of how one worn component can compromise overall combine performance.
"A lot of guys put extensions on their grain tank and fill those grain tanks a couple feet beyond the end of the grain tank loading auger," he says. "When the end of that loading auger is buried, it risks overloading the entire clean grain system, all the way down to the shoe. The buried loading auger can’t get rid of grain fast enough, which overloads the clean grain elevator, which overloads the lower clean grain auger and shoe."
Kent Hawk, combine specialist with John Deere, notes that grain tank loading augers with worn flighting exemplify the problems of any worn auger in a combine.
"Worn augers increase grain damage," says Hawk. "As auger flighting wears thin, the diameter of the auger is also reduced, so there’s more room between the edge of the auger flighting and the auger housing. Grain gets tumbled between the sharp edges of the worn flighting and the auger housing. Not only do you get increased grain damage, but it takes more power to move grain when augers are worn."