Self-Propelled Analysis

March 24, 2012 07:45 AM
Self-Propelled Analysis

Define what you need, then know what to look for

Iowa farmers Dustin Ritter and his father, Pat, faced a decision this past winter: buy another tractor or replace their pull-type sprayer with a self-propelled sprayer.

"We always seem to end up needing to spray corn when we’re still planting beans, and our planter tractor was also the sprayer tractor," Dustin says. "We decided we had enough acres and did enough custom spraying to justify a self-propelled sprayer rather than buy another tractor that we really didn’t need except in the spring."

After using the Internet to research, the Ritters devised a list of must-have options, such as auto-steer and automatic boom height control, and settled on a price range.

"There are different levels of self-propelled sprayers, designed for different parts of the market," says Jason Pavlu, a salesman with Simpson Farm Enterprises in Ransom, Kan. "The key is to match the capabilities and price range to your needs."

Establishing concrete goals helps buyers stay focused in the often confusing used sprayer market. Options range from tricycle-type sprayers with 300-gal. tanks and 60' booms to mega-sprayers that tote 1,200 gal. per load, with booms that span 120'.

Visual and technical check. The visual appearance of used sprayers should carry a lot of weight, agree Pavlu and the Ritters.

"The hour meter doesn’t tell the story on sprayers like it does on tractors," Pavlu says. "Sprayers tend to have relatively low engine hours. It’s how the sprayer was operated during those hours that makes a difference. Sprayers run at higher groundspeeds, so they bounce around more. The booms are wide and get bent on trees and fence posts, and chemicals get spilled and damage the paint and start corrosion. Booms and overall condition concern me more than engine hours," he adds.

When shopping, the Ritters learned to look for damaged booms, rough paint and other indications of hard use and little attention to maintenance.

"We got to the point where we’d walk up to a sprayer, look at the booms and know if it was worth checking closer," Pat says. "I can accept the breakaways on the ends of the boom being a little bent and welded, but welds and patches on the main booms usually meant the rest of the
machine was rough, too. If the booms looked good, I’d keep looking around at the mechanical parts of the sprayer while Dustin jumped in the cab and checked out the high-tech stuff."

The younger Ritter says the control consoles in the cab offer insights into the condition of the technology components.

"I’d look at the diagnostics pages to see if there were any warning codes, look at the total acres sprayed and see how the systems were set up," Dustin says. "We knew we wanted auto-steer, swath control, automatic boom height control and other specific options, so I’d check to see if those were inte-grated into the machine or if they were add-ons. I think integrated systems work more smoothly than add-ons, and they definitely reduce the amount of clutter from harnesses and consoles in the cab."

Nitty-gritty inspection. If the initial visual and technical inspection of a sprayer is promising, the Ritters say, it’s time to "get picky." The challenge is to know what to look for and where to look for it.

The key points to inspect on a RoGator differ from the key points on a SpraCoupe, which differ from the key points on a Hagie. But there are generic areas involving all used self-propelled sprayers that deserve specific attention:

  • Inspect all aspects of mechani-cal/chain drives on nonhydrostatic machines. Excess free play in drivetrain couplers, U-joints and drive chains merits closer analysis.
  • Pull the drain plugs on all final drive hubs. Rank-smelling, discolored gear oil justifies further investigation, perhaps with a flexible magnet to see how much metallic contamination is in the bottom of the gearcase.
  • Many driveshafts, from engines to differentials and hydrostatic drive units, are buried beneath cabs or spray tanks, making them difficult to grease. They’re even more difficult to replace if a "dry" U-joint fails.
  • Check the inside of wheel rims for oil from leaky wheel motors or hose fittings on hydrostatically driven machines. Shine a flashlight underneath spray tanks, cabs and mainframes to identify hydraulic leaks.

Boom focus. If a self-propelled sprayer passes static inspection, start the machine, move it to an open area and unfold and then refold the booms. Consider these points:

  • Bent booms sometimes unfold but have difficulty returning to their transport rests. Abnormal boom movement during folding and unfolding deserves closer inspection.
  • With the booms unfolded, check the operation of any automatic boom height control system. Moving a hand or hat under a boom height sensor should trigger that section to raise.
  • Position the boom at chest height, shut off the sprayer and visually inspect every foot of spray hose on the boom. Inspect every nozzle body and hinge assembly. It’s time-consuming and boring to closely inspect a 120' boom, but it ensures there will be no surprises with the sprayer.
  • Note whether the previous owner has installed protective sleeves along wear-prone sections of hydraulic and spray hoses. Protective sleeves can denote potential problems, but they can also be a positive sign because they indicate an operator who took time to worry about preventive maintenance.
  • Note the condition of the foam marker system. Air and liquid supply lines should be unkinked where they pass through boom hinges. If the weather is warm enough so the system doesn’t have to be rewinterized after testing, add water and soap to the foamer tank to see if the system creates foam and can alternate foam production from side to side of the boom.
  • If the weather is warm enough, add at least 100 gal. of water to the spray tank and do a dead-head test of the spray pump: turn off all the boom valves, turn on the pump, run the engine to full revolutions per minute and see if the pump can produce at least 80 psi to 100 psi when working against a "closed" system.
  • If possible, spray water from the entire boom. Check to see if valves controlling individual boom sections turn off and on appropriately.
  • Turn off the spray pump and the engine and reinspect the boom, especially the nozzle bodies and boom section control valves, for leaks. Inspect the main spray pump and spray supply lines for leaks, splits or bulging hoses.

If cold weather or other circumstances prevent spray-testing the machine, Pavlu encourages potential buyers to at least drive the sprayer around the sales lot, farmyard or down a road to check basic mechanical functions and in-cab technology.

"You can drive a sprayer with the booms folded and the pump off, create an A-B line and check out the auto-steer or row guidance," he says. "You can test most of the high-tech stuff in the cab without going to the field or putting water in the tank and spraying."

Once the mechanical and technological condition of a sprayer has been determined, it’s time to begin price negotiations. Sticker shock is common for first-time buyers.

"It’s a big price jump from a pull-type to a self-propelled sprayer," Dustin says. "We decided that the ability to cover more acres in less time, without buying another tractor we didn’t need, was worth the cost."

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Spell Check

3/25/2012 02:57 PM

  Having owned several self propelled sprayers, I would suggest avoiding used hydrostatic driven units, repairs will happen with a hydro drive and they can get very expensive. I now have just traded for our second Apache (which is mechanical drive) and it is a joy to operate. We traded our first apache off and never had any major repairs except some tree related boom damage. The mechanical drive system had no repairs unlike a Wilmar with Hydrostatic drive we had and you budgeted at least $2500 /year for hydro repairs.


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