Sprayer Will Not Build or Hold Pressure (All Manual Pump and Compression Sprayers)

Applies to: All manual pump-up and compression sprayers sold by The Fountainhead Group, including Field King, Smith, Grab & Go, DEWALT, CRAFTSMAN, HDX, Roundup, Scotts, and Ortho manual sprayers. Battery-powered sprayers are covered separately in the Battery and Charger Troubleshooting Quick Guide.

What causes this: A manual sprayer builds pressure by pumping air into a sealed tank. If air is escaping anywhere, pressure will not build or will not hold. In almost every case one of five things is letting air out: dirt or debris on the pump gasket or tank closure; a pump gasket or tank cover O-ring that is chipped, torn, swollen, or worn; a check valve at the bottom of the pump assembly that is missing or damaged; a piston O-ring that is dry, worn, or damaged; or a hose that is loose at the tank connection.

How to fix it: Work through these in order. Depressurize the sprayer and empty the tank before you start.

1. Clean the seal. Remove the pump assembly. Wipe any dirt or debris off the pump gasket (or tank cover O-ring) and off the tank closure surface where it seats.
2. Inspect the gasket or O-ring. If it is chipped, torn, swollen, or clearly worn, replace it. This is the most common cause.
3. Check the check valve. Look at the bottom of the pump assembly. If the check valve is missing or damaged, replace it.
4. Inspect the piston O-ring. If it is dry, lubricate it as described in the Maintenance section of your manual. If it is worn or damaged, replace it.
5. Reseat the hose. Re-insert the hose barb at the tank connection and tighten the hose nut.
6. Test with water. Reassemble the pump, fill the tank with plain water, pump it up, and confirm it holds pressure before putting chemical back in.

If it still will not hold pressure, or you are not sure which part you need, find your model number (see How to Find Your Sprayer's Model Number) and look up the article for your specific sprayer, which lists the exact gasket, check valve, and O-ring part numbers.

Need a part? Order at shop.thefountainheadgroup.com. Warranty claim or registration? thefountainheadgroup.com/register. Anything else, call The Fountainhead Group at 1-800-311-9903.