I have a problem with a Fiac/Black and Decker CP5050 air compressor. I need to find an exploded drawing of the compressor or a comprehensive manual. The compressor comes up to pressure normally and hold it. If I use a spray gun, it gradually losses pressure until the gun doesn't work. If I stop using the gun the pressure comes back up. I've checked the filters and unions and they seem fine. Can anyone help please?