Condensed Guide for Cleaning and Storing Field Sprayers By Bill Casady

The following cleaning procedure is recommended for all herbicides unless more specific instructions are listed for a particular product.

Cleaning
Add one-half tank of fresh water; flush tanks, lines, booms and nozzles for at least five minutes using a combination of agitation and spraying. Rinsate sprayed through the booms is best sprayed onto cropland to avoid the accumulation of pesticide-contaminated rinsate.

Thoroughly rinse the inside surfaces of the tank, paying particular attention to the surfaces around the tank fill access, baffles and tank plumbing fixtures. The use of a 360-degree nozzle, such as the TeeJet Model 27500E-TEF rinsing nozzle, permanently installed to the spray system can automate the thorough cleaning of tops and sides of the tanks. Several nozzles may need to be positioned carefully to clean tanks with baffles.

Pressure sprayers are useful for removing caked on internal and external residues. Hot water can increase penetration of dried residues, but the addition of hot water rinsing may cause unacceptable health hazards due to the vapors produced. Carefully review label safety precautions for the agrichemicals and cleaning products used. See MU publication G1917, Personal Protective Equipment for Working With Pesticides.

Fill the tank with fresh water and add one of the following cleaning solutions or a commercially available tank cleaner and agitate the solution for 15 minutes. Add one of the following to each 50 gallons of water to make a cleaning solution: two quarts of household ammonia or four pounds of trisodium phosphate detergent.

Operate the spray booms long enough to ensure that all nozzles and boom lines are filled with the cleaning solution. Let the solution stand in the system for several hours or overnight. Agitate and spray the solution onto an area suitable for the rinsate solution.

Add more water and rinse the system again by using a combination of agitation and spraying. Remove nozzles, screens and strainers, and clean separately in a bucket of cleaning agent and water. Finally, rinse and flush the system once again with clean water.

Storing
After thorough cleaning, remove nozzles and pumps and allow all parts of the sprayer to dry thoroughly. Seal all openings with tape or rubber stoppers to prevent insects, rodents and pests from nesting in the equipment. Then store the sprayer in a clean and dry location, especially when it will sit through the freezing weather of winter months.

Remember, maintenance is also a much more appealing job while the sprayer is clean. Before you back the sprayer into its final resting spot, perform a thorough inspection of all systems and make a list of needed repairs. While the sprayer is still clean, perform a thorough calibration and any maintenance needed to make it spray like a new one.

Bill Casady
Agricultural Engineering
573-882-4370