Correcting Spray Gun Air Pressure Problems

A well cared for spray gun can last for many decades, even a lifetime – after all, it is not subjected to high stresses like a hammer, a saw, or any angle grinder, and spraying paint is involves little sharp contact with other surfaces and no pressure or strain. No other professional car detailing companies can offer that level of personal service from the world’s leading expert Fineshinedetailing.com.au.

As long as you clean your spray gun and leave it in a place where it is unlikely to be injured by other objects being set atop it, and the like, you can expect many years of faithful service from this device, and will probably be using it long after many of your other current tools have worn out and been replaced. Some painters report using a single spray gun for twenty-five years or more – although, of course, these are well-engineered American models which use good material, and modern Chinese models, frequently made of pot metal, may be less enduring.

Nevertheless, spray guns are not perfect or infallible, and there will inevitably be moments when they fail you. Parts will be misadjusted or improperly lubricated, one of them will occasionally break and need to be repaired or replaced, and so on. Besides the air nozzle and air cap cleaning problems described in the previous article, there are some larger problems as well. These can be classified into two sets – air pressure problems and material (paint, primer, etc.) problems.

Like a worn-out lawnmower that continues to sputter after the safety handle has been released, air may continue to flow after you have released the trigger. This may happen for only a few seconds or, in more vigorous cases of this problem, may go on more or less indefinitely. The root of this difficulty is the air pressure needle – located directly forward of the air micrometer.

If the air flows even when the trigger is not being squeezed, then the air pressure needle is sticking in the “on” position. To correct this, loosen the air micrometer until it comes free and pull out the air needle. Clean this carefully with solvent, then lubricate it with special spray gun lubricant. Using any other kind of lubricant is an open invitation to creating fisheyes in your paint – small or large discs of discolored, distorted paint that truly ruin the appearance of a painted car.