Troubleshooting Compression Sprayers

If your sprayer is not working properly, check the following list to analyze the problem. Then follow the steps in the order they are given. Try the second step only if the first one does not work.

Problem: Sprayer does not pump up. No resistance when pumping.

Analysis: Plunger cup is not in contact with cylinder walls.

  1. Squirt a tablespoon of oil in top of cylinder to lubricate cup.
  2. Pry handle from cylinder. Check cup at bottom. If it’s leather, rub oil into it until it’s pliable. If it’s nylon or rubber, check for wear. If necessary, replace with new cup.

Problem: Air hisses out from top of tank when pumped up. Does not hold pressure.

Analysis: The cylinder seal is dirty or worn.

  1. Clean cylinder seal and reseal.
  2. Replace seal.

Problem: Liquid from tank fills cylinder and wells out of hole in top.

Analysis: Gasket at bottom of cylinder is dirty or worn.

  1. Clean gasket.
  2. Replace gasket.

Problem: Air leaks from hose connection to tank.

Analysis: Connection isn’t secure. Depending on sprayer:

  1. Be sure cap nut and lock nut are threaded down tightly. If that doesn’t help, release pressure, remove cap nut, and pull out supply tube. Remove lock nut. Remove inside fitting from tank through pump opening. Remove O-ring and clean surfaces where O-ring seals. If necessary, replace O-ring. Or. . .
  2. Inspect hose and clamp. Tighten or replace clamp. Check hose for splits. Cut off worn area and refit hose on tank.

Problem: Does not spray when pumped up.

Analysis: Spray wand is plugged up.

  1. Unscrew nozzle. Clean with round toothpick or copper (not steel) wire. Do NOT place to lips to blow out.
  2. Clean holes in ends of wand.
  3. Clean port at spray control valve.

Problem: Spray does not shut off cleanly.

Analysis: Air is in the line.

  1. Refill sprayer if it’s empty. Keep tank in upright position. Do not agitate while spraying.
  2. Clean and, if necessary, replace O-ring or gasket at spray control valve.

Problem: Sprayer does not shut off at all when handle is released.

Analysis: “Constant-on” latch is engaged or wand is loose.

  1. Release “constant-on” latch.
  2. Tighten wand at end of spray control valve.

Problem: Spray pattern is uneven.

Analysis: Nozzle is dirty or plugged.

  1. Clean nozzle as described above.
  2. Replace nozzle.