i have an iwata hp-c and the trigger is sticky. When I release it is slow to close and blows by a bit. I think I gummed it up since my packing seal on the needle needed tightening and was blowing paint into the trigger area. Fixed that. Also I've been putting lube on the trigger and may have gummed it too. Question is how hard is it to remove the assembly, and might I need a new assembly? If I have the stem packing seal too tight would that argument the problem?