Blog Airless Sprayer, Paint Pump, Airless, Schematic

Published on October 29th, 2013 | by Grant Barnard


Airless Paint Sprayer Won’t Prime – Paint Pump Problems

Airless Sprayer, Paint Pump, Airless, Schematic

There is nothing more frustrating than your airless paint sprayer not working. The paint pump is the thing that is supposed to make your job easier. However it has to draw paint and prime properly before it can work.  So when the sprayer won’t pump paint, it kills your day. Always remember that if you are local and need the services of an Indianapolis Painters, call Grants Painting at (317) 800-4540.

The Most Common Sprayer Prime Problems

Inlet Ball

The inlet ball can get things in it that the rock catcher wont stop. This will totally stop the prime. The Fix – There are two fixes depending on the severity of what got the inlet ball to not seat properly. One is that you can simply give the bottom of the fluid section a couple good taps when its running. A few rounds of good taps with a hammer will usually do it. If that wont do it you may have a clump of dried up paint from the the sprayer. To fix this you will have to remove the bottom of the fluid section from the sleeve. This is done by removing the suctions hose and then the bottom of the fluid section from the sleeve by tapping it loose and unscrewing it. In there you will find a ball and sort of a cage for the ball(shown on right). Both items can be removed by tapping them with a hammer and screwdriver. Then of course a good cleaning will help you out. There is sometimes other seals in there so be careful to not lose any parts.

Upper Ball Valve

Sometimes, but rarely, you will have the upper ball stick when it should be releasing. To fix this you just need to pop the piston outlet ball up with just about anything that you can stick up there. Try to be careful not to nick up everything in there with a metal screwdriver. Usually a stick will work just fine. You will know if this is the problem because when you pop that ball up you will feel and hear a very slight pressure release. While this is rarely a main cause, when having issues this helps the start up process.


This problem is obvious because it really the only problem that happens gradually. If you have run quite a bit of paint through the system you might need to replace some common wear parts including packings. Having problems regularly with your pump is indicative of just some good ol’ maintenance is needed. Now this really can depend on what you are running through your pump but you can figure anywhere between 200 and 500 gallons of paint. Primers, thicker paints and cheap paints with sediment are all things that will destroy those packings quicker. Using the separator oil is the best way to protect your pump’s packings.

Of course all of these paint sprayer problems can be prevented with some easy care and correct operation. Please read the extension of this article: Easy Operation Of Your Airless Paint Sprayer.


Tags: , , , , , , , , , , ,

About the Author

Grant Barnard started painting in 2000 and started Grants Painting in 2008. Originally doing business in northern Indiana, the business was moved to Indianapolis and Greenwood shortly after. Today the Grants Painting has blossomed into a reputable painting contracting company with an ever growing extensive website including our How To DIY Articles. Grants Painting covers all aspects of coatings and specialized in epoxy flooring, interior painting, exterior painting and cabinet painting.

  • Ski

    Thanks for the answers. This was the best site I’ve seen on airless sprayers.

Back to Top ↑