My 1985 Chevy Silverado 4x4 350 w/Holley carb and automatic trans has a problem when it starts up it will idle fine, once it warms up it looses power and then idles rough runs rough, and eventually won't stay started.

I am only a weekend mechanic at best and have try reseting the timing, changed out the fuel pump, and replaced some cracked vaccum hoses.

Another separateproblem that I have is when I fill up with gas sometimes the fuel pump won't give me a constant flow without stopping. The automatic cut-off shuts the pump off like it is full. So, then I wait until the next day try again on the same pump and it works. It does not happen everytime obviously, but no one that I talk to knows what is going on.