Bad Gas or what?

[Gpaw44]

Last week my truck ( 86 GMC 4.8 engine) started haveing a rough idle so I replaced the in line fuel filter and the carburetor filter and added some sea foam thinking it may have some moisture in the tank or bad gaa. The idle smoothed out but now I might be able to go about a mile before it dies. The first two time it died I let it sit for about an hour and it started right up. The third time I did not let it sit but pured a little bit of gas in the carb and it fired riight up and I was able to get it off the street. So I'm thinking is not a electrical issue but a fuel issue.
Is this a carburetor issue or a fuel pump going bad. I can see gas in the inline fuel filter at all times while it is dying.
Thanks for any suggestions for what to look for.

 

[fast 99]

Check fuel pressure and volume.

 

[Grit dog]

Sounds like dying fuel pump. Quick test, when it dies, disconnect fuel line to carb and crank it. If it’s not pumping gas handily then I’d say that’s it.
Although starts and runs again by priming the carb could be vapor lock? But presumably has a return line which prevents vapor lock in most situations.