May 11, 2014
Catastrophic breakdowns of planters are easy to diagnose and it's easy to justify their repairs. A drill shaft breaks, and you either fix it or you can't plant.
It's tougher to diagnose problems that develop because of wear to multiple components. A worn seed unit drive chain will go around its sprockets just fine, but can crawl and jump teeth and cause hard-to-diagnose problems with low populations in that row. The same goes for worn sprockets--yes, they still "grip" the chain links, but under load they can either jump a tooth, or even worse, snag and jerk the chain with worn, hooked teeth.
Planter bearings are notoriously prone to failure with little visible evidence of the failure. Planter driveshafts turn slowly, so failed bearings don't fly apart and draw attention to themselves. They just get stiffer and stiffer, occasionally grabbing and catching to cause mysterious blank spots in multiple rows that are too short to show up on the seed monitor during planting. They only show up as multi-row empty spots once the crop emerges.
Wear- and age-related mechanical issues on planters are tough to diagnose, but it's even tougher to justify spending money on preventive maintenance. The parts don't look "broke." They "work," as in, the shafts and bearing turn. And when you start pricing a dozen or more drive chains and twice that many drive sprockets, along with associated bearings, you're looking at a sizeable check. Add the cost of paying a mechanic to do the work, and that "good ol' planter" suddenly becomes expensive.
The reason for this blog topic is because I spent a total of 16 hours and multiple trips over the past week trying to diagnose problems in an older planter. Final diagnosis is still up in the air, but so far I've replaced a worn clutch, a worn driveshaft, worn main drive sprockets and worn main drive chain. None of the parts were broken. None of the parts were worn enough to cause problems by themselves. But each part added a little extra drag, an occasional jerk, or some other minor glitch to the overall planting process that contributed to a planter that wouldn't plant even close to correctly.
Would the farmer have paid to replace all those parts ahead of the season? Probably not, because the repairs would have cost more than half the value of the 20-year-old planter, and in the words of the farmer, "they aren't totally worn out yet."
Sometimes a little wear "here" and a little wear "there" add up to a major breakdown "now."