Airless Spray gun spitting or not shutting off completley possible causes.
Paint spitting from your airless spray gun when you pull the trigger or release the airless spray gun trigger can be annoying and ruin your airless paint spray job.
Spitting airless paint spray guns can be caused by several common issues.
Spitting when using an airless spray gun extension pole at the point of triggering on or off is very common. This is due to the fact that the on off valve in a spray gun is moved further away from the airless spray tip by the airless spray gun extension pole being placed between the spray tip and airless gun.
Airless spray machine manufacturer Graco have a handy accessory to eliminate this phenomena when using airless spray gun extension poles. The Graco CleanShot valve can be attached to any airless spray extension and provides a paint shut off at the tip where the airless gun shut off used to be before the poll was fitted. This Graco CleanShot valve assembly virtually eliminates this type of airless spray gun paint spitting.
If an airless spray gun extension pole is not being used and your airless gun has started spitting paint when you begin to spray and when you stop spraying, or one of these, and this did not occur previously then there may be wear on the shut off valve in the airless spray gun, or there may be dried paint or other debris causing the airless gun to not shut off correctly.
To investigate this issue the seat will need to be removed from the airless spray gun and the valve ball and seat inspected. Procedures may resolve the issue otherwise replacement of the airless spray gun ball and seat assembly may be required.
Before disassembling the airless gun check that there is not a build up of paint around the airless spray tip which is causing the spitting when the gun begins to spray. This could be another cause of paint spitting.
Another check to make before disassembling the airless gun and spending money on parts is to wash the machine out and test with a thinner liquid such as water. If the airless gun continues to dribble after the trigger has been released then the valve assembly in the gun is either worn, damaged or dirty.
Many airless spray machine operators forget that the airless spray gun has internal components that require storage protection the same as your airless spray pump requires. The airless spray gun and potatoes hose should be completely filled with airless spray machine pump saver or other anticorrosive storage liquids when the airless spray machine is not in use to avoid corrosion, drying of residual paint and premature airless spray machine component failure.
Correct cleaning and storage procedures will ensure your airless spray machine avoids premature failure through component corrosion which airless spray machine manufacturers cannot cover under any warranty.