when i push down just for air paint comes out, very frustrating.... i have changed the needle, i have adjusted the amount of paint coming out, and suggestions, i have pulled the ab appart and have lubricated and cleaned the ab,
Suggestion one , When asking for help give all details , What make and model of airbrush is it? What PSI are you spraying at? What brand of paint are you using?
Different airbrush even thou the basic make up are pretty much the same , Have different ways parts go and fit to them.
Most time when you have paint coming on when the trigger is in the air on position it is due to a couple of common things. Paint dried in the nozzle not allowing the needle to seat like it should, Cracked Nozzle which allows the paint to flow past it.
The needle bearing acts like a valve that will stop the paint from flowing into the trigger assembly, Most time if it is allowing paint to pass through it will not allow it to come out the needle end of the gun. Why ? Because there is no air passage for that paint to hit unless enough is leaking to pool around the air valve assembly .
Now when you say you have adjusted the amount of paint that comes out , To me that sound more like a single action airbrush. not a dual action, Single action does allow you to adjust the amount of paint that comes out because when you press air on it is also paint out. Where dual action is just that press straight down for air on, and than pull the trigger back to allow paint to flow. the farther you pull back the larger the amount of paint and the bigger the pattern you will get.
So For advice that will help you please tell us what airbrush , paint and at what psi you are working.