The supply (siphon) tube may be loose or missing. First, make sure pressure is released from the tank. Then, remove the hose from the tank by unscrewing the coupling. Lift off the hose. If the supply tube is not attached, check to see if it’s loose inside the tank. If it is, remove it from the tank and insert it into the hose at the coupling, and reattach the hose to the tank. If tube is missing, call 1-800-9-SPRAYER for a replacement.

Follow instructions in your owner’s manual to disassemble the pump assembly. Check the plunger cup to make sure it is correctly attached. Add a little petroleum jelly. Inspect the check valve at the bottom of the cylinder to make sure it is on and is not obstructed by dirt. Reassemble. If problems persist, plunger cup or check valve may need replacing. Check your retailer or call 1-800-9-SPRAYER for a parts kit.

Chances are there is dirt or debris somewhere in the discharge line. Most likely the nozzle is plugged. RELEASE THE PRESSURE by slowly opening and removing the pump. Then, unscrew the nozzle cap and check to see that it’s clear. With the nozzle cap off, check the holes at the nozzle end. You may need to clean them or the nozzle cap. If the nozzle needs cleaning, use a broom straw or toothpick. Remove the wand from the end of the hose or shutoff. Run water through it with the garden hose. Remove the hose from the tank and with the on/off valve open, run water from the garden hose through it. Also, make sure that what you are spraying is not too thick. Very viscous (heavy or syrupy liquids) will not spray properly from any hand sprayer.
Check the gasket on top of the pump cylinder. It may be dirty and won’t seal correctly, or it may need replacing. Your dealer should have a replacement or you can order a parts kit by calling 1-800-9-SPRAYER. TIP: Put a bit of petroleum jelly on the gasket. The pump should seal with little turning pressure on the pump…not much more than “finger tight”. Trying too hard to tighten down the pump, especially the first time, may damage the gasket and actually work against you. You may download specific parts breakdowns for the Hudson sprayer you own. See Download Schematics on the product page of your spayer. For service information or parts ordering, phone 1-800-9-SPRAYER.
Clean O-ring and seating surface on control valve. Replace O-ring if worn.

Clean O-ring in wand and sealing surfaces. Replace O-ring if worn.
Lubricate plunger cup with petroleum jelly, (not oil), or replace plunger cup.
Clean O-ring on wand and sealing surfaces. Replace O-ring if worn.
Clean gasket sealing surfaces or replace gasket.
Be sure gasket is tight. If O-rings are used, clean sealing surfaces or replace O-rings; re-attach hose.
Clean check valve sealing surface or replace check valve.