I have a 54 chevy pickup with the 235 6 in it. It is stock . I am having problems keeping the fuel filter full? I have put an elec fuel pump on it an that worked for a while till it shorted out. So I went back to the stock manual pump and it works some times but then it will just keep enough fuel to keep it running. Sometimes? I just bought a new pump ( manuel) for it today thinking that the old one might have a problem. But it does the same thing> I have a glass fuel filter on it so I can see what is going on. It keeps about 1/4 of the filter with fuel? I have replaced everything from the tank to the carb?New tank unit,New lines,& rebuilt the carb. HELP! I don't know what else to try!