Source: Ohio State University Extension

It's very likely you've already completed the harvest season and are in the process of storing all the equipment in a proper place. One piece of equipment requires more attention than others when putting it in the storage place: the sprayer. If you want to avoid potential problems and save yourself from frustration and major headaches, you will be wise to give your sprayer a little bit of TLC (tender loving care) these days. 

Yes, this is still a busy time of the year for some of you, but don’t delay winterizing your sprayer any more than necessary. The sub-freezing temperatures are just around the corner. This may not have any bearing on your planting or even harvesting equipment, but sprayers require special attention, mostly because of the liquid that may be left in some components of the sprayer.

Sprayers, just like any other piece of equipment should be protected against the harmful effects of snow, rain, sun and strong winds. Moisture in the air, whether from snow, rain, or soil, rusts metal parts of unpro­tected equipment of any kind. This is especially true for a sprayer, because there are all kinds of hoses, rubber gaskets and plastic pieces all around a sprayer. 

The sun usually helps reduce moisture in the air, but it also causes damage. Ultraviolet light softens and weakens rubber materials such as hoses and tires, and degrades some tank materials. How about the pump, the heart of a sprayer? You don’t want a pump that is cracked and/or not working at its full capacity because you did not properly winterize it before the temperature falls below freezing.

The best protection from the environment is to store sprayers in a dry building. Storing sprayers in a building gives you a chance to work on them any time during the off-season regardless of the weather conditions. If storing in a building is not possible, provide some sort of cover.

Here are some suggestions you may want to follow as you prepare the sprayer for storage: 

1. When storing trailer-type sprayers, put blocks under the frame or axle and reduce tire pressure during storage.

2. It is very likely that you did the right thing when you used the sprayer the last time: you rinsed the whole system (tanks, hoses, filters, nozzles) thoroughly. 

If you did not, make sure there is no leftover spray mixture in the tank. Dispose of it according to the chemical label, and rinse the system with some sort of a rinsing solution. Usually a mixture water containing 1%  household ammonia (for example 1 gallon ammonia for 100 gallons of water; ½ gallon of ammonia for 50 gallons of water, etc.) should be adequate for cleaning the tank, but you may first need to clean the tank with a mixture containing detergent if the tank was not cleaned weeks ago, right after the last spraying job was done.

3. Cleaning the outside of the sprayer components deserves equal attention. Remove compacted deposits with a bristle brush. Then flush the exterior parts of the equipment with water. A high-pressure washer can be used, if available. Wash the exterior of the equipment either in the field away from ditches and water sources nearby, or a specially constructed concrete rinse pad.

4. Drain all cleaning water from all parts to prevent freezing.

5. To prevent corrosion, remove nozzle tips and strainers, dry them, and store them in a dry place. Putting them in a can of light oil such as diesel fuel or kerosene is another option.

6. Pumps require special care. After draining the water, add a small amount of oil, and rotate the pump four or five revolutions by hand to completely coat interior surfaces. Make sure that this oil is not going to damage rubber rollers in a roller pump or rubber parts in a diaphragm pump. Check the operator's manual. 

If oil is not recommended, pouring 1 tablespoon of radiator rust inhibitor in the inlet and outlet part of the pump also keeps the pump from corroding. Another alternative is to put automotive antifreeze with rust inhibitor in the pump and other sprayer parts. This also protects against corrosion and prevents freezing in case all the water is not drained.

7. Cover openings so that insects, dirt and other foreign material cannot get into the system.

8. Finally, check the sprayer for scratched spots. Touch up these areas with paint to eliminate corrosion.