5.9 l runs out of fuel overnight, won’t prime

1989 grand Wagoner 5.9

Just got this in, thought I'd pick " the brain" before I dig in

Issue: if you prime the carb, it will run all day, start fine etc

It sits overnight, and no matter what you do or crank, won't prime the carb. Once you hit it with starting fluid, it will prime, and go all day

1. 2 rebuilt carbs, 2 new fuel pumps, filters, new gas tank

I'm thinking these have a pushrod on the pump? I haven't dug into it yet
Author: mopar440