4-WD Sprayer "Not Just Another Combine Rig"

4-WD Sprayer "Not Just Another Combine Rig" SPRAYING Miscellaneous 30-2-34 "I built a state-of-the-art self-propelled, 4-WD sprayer out of a 1987 Case IH 1660 combine for only about $60,000. That's only about one third the cost of a new self-propelled sprayer," says Gary Koehler, Upper Sandusky, Ohio. The sprayer is equipped with a 1,200-gal. stainless steel tank off a John Blue sprayer, as well as an 80-ft. hydraulic-fold boom equipped with nozzles on 20-in. spacings. The front axle was formerly the combine's rear axle, and the rear axle is a Mud Hog hydraulic-driven axle. The engine, transmission, radiator, hydrostatic pump, cab, ladder, and air cleaner are all off the combine. The rear wheels have 46-in. dia. rims and the front wheels have 34-in. dia. rims. He paid $12,000 for the combine at an implement dealer. He stripped the combine completely apart and built a new frame. He moved the combine's engine over the front axle and used sheet metal to make a hood for it. Hydraulic wheel motors are used to power the front axle. He relocated the combine's transmission to the back of the machine and turned it around to face forward. He also reversed the combine's hydrostat hoses to make the transmission go in the opposite direction so that the rear drive wheels operate correctly. The sprayer has about $2,000 worth of hydraulic oil coolers on it to keep the hydraulic oil cool. The sprayer is equipped with a Tee Jet light bar that mounts on the hood, and a receiver that mounts on top of the cab. A Micro-Trak unit is used to control the spray. The sprayer still has the combine's original air ride seat. There's a hydraulic-fold ladder on one side of the cab (he used the original ladder off the combine and mounted a hydraulic cylinder on it). The 100-gal. fuel tank is off a Freightliner semi tractor and mounts on one side of the machine. The hydrostat oil reservoir mounts on the opposite side of the machine. The muffler came off a Deere 4440 tractor and he made the air intake out of 3-in. dia. steel pipe. "I use it to spray herbicides and insecticides on corn and beans and to top dress 28 percent nitrogen on wheat. I really enjoy driving it," says Koehler. "The only limitation is that it doesn't have air ride suspension so it rides a little rough. This is the third self-propelled sprayer I've built out of old combines over the years. My dad Vernon and my brother Jerry and son Jason helped me build this one. I use a 16-row, 30-in. corn planter that's exactly 40 ft. wide, so the 80-ft. boom matches up perfectly." Koehler says he used the Case combine because the engine is not computerized, which makes it much simpler to work on. "If something goes wrong with the fuel injector or pump, there's a good chance that I can fix it myself instead of having to call someone." He paid $14,500 for the boom which is made by Precision Mfg. "I had Unverferth build special wheels for me which cost about $5,500. The wheels are 1 in. thick at the center so I don't have to worry about busting them." Koehler flips an electric switch in the cab to engage the hydraulic motors that drive the front axle, which reduces the machine's speed by half in the field. "Whenever I want to go on the highway, I turn the switch off and the machine will return to normal speed. I can go up to 25 mph on the highway," he says. Even though he saved a lot of money by building his own self-propelled sprayer, Koehler says he could have built it even cheaper if he wouldn't have had to rebuild various components. "I had to rebuild the Mud Hog axle at a cost of about $2,000. Also, the engine needed a new turbocharger and fuel injector pump, which cost a total of about $1,400. And I had to spend about $4,000 to repair the hydrostat unit which had gone bad. Without these extra expenses, I might have been able to build my sprayer for only about $40,000." Contact: FARM SHOW Followup, Gary Koehler, G & J Koehler Farms, 8366 Township Hwy. 103, Upper Sandusky, Ohio 43351 (ph 419 294-3901; gary@udata.com).

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