Tiny bubbles in the In- line fuel Filter- not the wine!

[TallJohn]

Greetings from sunny Sacramento Calif. Started up my 64 yesterday and was tinkering around. I noticed the clear in- line fuel filter was bubbling like an aquarium! The car was running OK. I checked the clamps at the fuel pump and filter and followed the line back to the metal line at the passenger door. Everything looked fine . The rubber between the fuel pump and the metal line just mentioned is old but nothing looked cracked or leaking. The line and clamps at the gas tank are new as I had the tank re-done about 8 months ago. Before I pull the gas tank and replace the fuel line leading up to the fuel pump, can anyone tell me if what I'm seeing is normal or has had a similar problem? Thanks. John.