Airblast Spring Start-up and Winterizing

Any description of airblast sprayer start-up must, contextually, make assumptions on how it was winterized for long-term storage. This cyclic relationship is why I use a chicken-and-egg title slide when giving this presentation.

Answer: It was the rooster.

The inability to describe one process without the other is further complicated by the possibility that the sprayer is brand new and was therefore never winterized. So, what follows is an attempt at a logical sequence of activities to restore a winterized sprayer, or initiate a new sprayer, for the spraying season. If the following steps conflict with those of the manufacturer’s, always follow the manufacturer’s. Do this for reasons of safety and to preserve any warranty.

New Equipment

If this is a new sprayer, you have an opportunity to perform some preventative maintenance.

Loosen, lubricate and re-tighten clamps. Always back gears off before tightening to avoid stretching them. (Image from Purdue Extension publication PPP-121: Preparing Spray Equipment for Winter Storage and Spring Startup)
Use double clamps on pressurized lines for added safety. Wider clamps are better and T-bolt clamps are better than worm-gear.
Put thread release on bolts and re-tighten with a torque wrench (not an impact tool). Use a paint pen to mark nut, washer and bolt for future visual checks.
Protect hoses and wires at rub points. Follow hoses and with a paint pen, number the hose-ends and connections for future reference.
Using a new tractor? You may have to re-calibrate to account for different gear ratios. When hitching a new sprayer, note that the distance from the ball on the drawbar hitch to the tip of the PTO should be ~14″. Don’t exceed maximum working angles for PTO shafts (usually <25 degrees).

Winterizing

Remove nozzles and look in the nozzle bodies for debris. Discard worn or broken nozzles.
Soak, scrub, rinse and store nozzles and nozzle strainers. You may replace them once the sprayer is clean, but I prefer to store them separately since they have to come back off during start-up.
Disconnect hoses where they attach to the booms and drain as much liquid from the sprayer as possible. (Image from Munckhof Sprayers)
Clean the sprayer (Triple rinse with cleaner) and scrub the exterior. Do not use pressure washers on bearings, fittings, pumps or any lubricated or moving parts.
Examine fan blades for cracks, build-up or nicks that can cause imbalance. Replace (not just repair) punctured entrance grills.
Don’t ignore tank damage. Poly tanks are prone to sun damage and cracks. Never climb into a tank to repair it. Quite often, replacement is the best option.
Clean and inspect wheel assemblies. It’s best to do this during winterization to prevent bearing corrosion as the sprayer sits all winter.
Remove any rust and repaint (or just touch up). Paint not only looks good, it protects.
The excellent YouTube channel Ask Tractor Mike proposed storing the PTO shaft indoors in two pieces, and to cut away a portion of the guard to facilitate reassembly later on. Also, use a paint pen to make the splines on the shaft for easier hook-up.
RV antifreeze is a 50% solution of antifreeze and water, with a rust inhibitor. It should not cause phytotoxicity is sprayed or dumped, but be sure to dispose of it away from water sources during start-up. Turn the pump to get antifreeze throughout the system. Close the nozzle bodies, loosely fit the tank lid and store indoors. (Image from Purdue Extension publication PPP-121: Preparing Spray Equipment for Winter Storage and Spring Startup).

Spring Start-up

When planning spring start-up, never assume the winterized sprayer is ready for immediate hook-up. Expect a minimum half day per sprayer.
Attempting to loosen or shift something that hasn’t moved in several months is risky. Pressure gauges snap off, fittings crack, welds break. Expect the unexpected and either have spare parts on hand, or a plan to get them quickly.
Parts are most likely to seize during the first spray. Bearings and PTO universal joints, especially.
Start-up is a good time to lubricate parts. Grease the guard ring bearing every 100 hours, the universal joint cross every 25 hours and the shaft and shear bolt regularly.
Insects, birds and rodents eat, or make homes, in sprayers. Professional rodent bait/traps, steel wool and peppermint oil/gel are possible solutions.
Check belt tension, alignment and wear. (Image from Purdue Extension publication PPP-121: Preparing Spray Equipment for Winter Storage and Spring Startup).
Pump maintenance is beyond this article, but change the oil every 500 hr or 3 months. Use a paint pen to write on the pump what type of oil it requires, and then date the filters.
Ensure tire pressure matches the ideal stamped on the tire. Or, if using less pressure to avoid spring compaction, ensure both tires have the same pressure.
Turn gauges using the nut, not the face. Ensure they are not opaque, leaking, plugged or resting above the zero pin.
On sprayers with mechanical agitators, look for prop wear and loose or damaged paddles. Fill the sprayer with water and looks for tank leaks. Tighten the bolts 1/2 turn if the packing gland on the agitator shaft is leaking. You may have to remove and repack the gland if the leak persists.
A reminder to always set the relief valve to the bypass position when starting up the sprayer. This is one reason why pressure gauges spike and can eventually fail.
Look for signs of hose wear and examine the sprayer for leaks while under pressure. Be careful when pressurizing the sprayer for the first time in the spring; this is when lines are likely to come loose or burst. (Image from Purdue Extension publication PPP-121: Preparing Spray Equipment for Winter Storage and Spring Startup).
Minerals chelate (i.e. scale) more readily on stainless steel than plastic tanks. In either case, the first tank of water and leftover antifreeze should be sprayed from the nozzle bodies with no line or nozzle strainers, and no nozzles. Replace them once the tank is sprayed out.
And finally, now that the mechanical side of the spring start-up is complete, calibrate the sprayer.

Thanks to Fred Whitford (Purdue University), Gail Amos and Mark Ledebuhr (Application Insight LLC) for reviewing the content of this article and for their helpful edits.

Sending
User Review
0 (0 votes)