Pre-Season Sprayer Checklist
The sprayer that breaks down in April is the one nobody looked at in March. Work down this list once before the season, mark anything that needs attention, and you'll leave with a parts list and the right tool for each fix. Your progress saves in this browser.
Which sprayer, and when?
The checklist
Tap OK, Needs work or Skip on each line. Tap a line to see how to check it. Work in order — tank to tip — so you're not re-doing anything.
What needs work, and how to fix it
Parts to order
Save it
Print the checklist for the shop wall or the cab, keep notes for next year, or clear it and start a second machine.
Pre-season sprayer inspection: why the order matters
Most spring breakdowns trace back to three things: rubber that dried out over winter (diaphragms, gaskets, hose), debris that settled in the system (strainers, nozzle tips, flowmeter), and a controller that was never re-calibrated after parts changed. Checking tank-to-tip in order finds the upstream problem before it shows up as a mystery downstream — a cracked suction hose looks like a bad pump; a bad pump looks like worn tips; worn tips look like a controller fault.
The 30-minute version
- Fill a quarter tank with clean water. Look under the sprayer while it fills.
- Clean all three strainers before you start the pump — suction, line, tip.
- Run the pump at spraying pressure for ten minutes. Walk the boom: every nozzle on, every nozzle off when the section closes, no drips, no weeps at the pump.
- Catch-test three nozzles across the boom against the chart. Over 10% means a new set of tips.
- Check the controller's flow cal, speed cal and section widths against the sticker on the flowmeter and the actual boom.
Winterizing a sprayer
In the Inland Northwest a sprayer left with water in it will crack a pump housing or a flowmeter body by January. Rinse, drain the lowest point, then circulate RV antifreeze (the -50°F pink kind, not automotive) with the boom on until every nozzle runs pink — then shut off with the boom still pressurized so the lines stay full of antifreeze. Pull the tips and strainers and store them in a coffee can in the shop; pull the console and the pressure gauge indoors. Order wear parts in the fall: lead times on pumps and Raven parts are shortest when nobody else is ordering.
Common questions
Pump has no pressure at start-up
Prime first — a centrifugal pump will not pull a prime through a dry suction line. Check the suction strainer bowl seal and the tank outlet valve, then look for a collapsed or cracked suction hose. If it builds pressure and then falls off, the suction strainer is plugging or the relief valve is stuck open.
Nozzles keep dripping after the boom shuts off
Diaphragm check valves in the nozzle bodies. Diaphragms harden over winter; replace the set — they're under a dollar apiece. See the nozzle body breakdown.
Controller shows a flow or speed error
Look the code up in the Raven error lookup. Most spring errors are a corroded connector or a flowmeter turbine stuck with debris, not a failed console.
How often do tips need replacing?
When a catch test reads more than 10% above the chart for that tip at that pressure. Stainless and ceramic last years; polymer tips spraying abrasive products can wear in a season. The calibration tool does the math.
Related
Sprayer calibration & tip check · Nozzle body parts · Strainer & mesh selector · Pump finder · Raven troubleshooting · Connector identifier · My Sprayer