I have one of those clear plastic fuel filters in the line just before the carb and it's usually almost completely empty. As it idles it'll run empty, a little fuel will run in, and it'll run empty again. My fuel tank, pump, and lines are all new. I even replaced the new pump with another new pump, but it works the same. My truck runs perfect though. I can punch the gas and take off as fast as that old 216 will go or run it up to 80 mph and she'll never starve for fuel. I've seen some filters that stay full and some (like mine) that stay almost empty. I don't know what causes either condition but mine's run like this for 9 years without an issue.
