ATT. carburetor GURUs please help

[Craigerf100]

Ok guys need some carburetor help
Edelbrock 600cfm manual choke
My original problem is when it started coughing and acting like it was flooded on start up. A bit of gas would cough up into the air when I had the air cleaner off.
This started shortly after I adjusted the throttle pump linkage cause I was having some lull on hard acceleration. I adjusted it back shortly after.
Once the the truck starts it runs great. Only when on start up Was there a problem.
And then the other day I shut it off to fill up; then it wouldn't start at all. it would turn over. But very little to no sputter or cough.

I've heard bad power valve possibly
I haven't had a chance to look at it.

What do U guys think it could be?

Thx