Chevrolet Repair: 81 c10 fuel system problem, fuel starvation, fuel pump filter

Question
QUESTION: My truck has new distributor plugs wires rotor button carb fuel pump filter and sending unit i believe it may be the fuel evap system that has no vacuum to it that is the problem tell me what u think

ANSWER: HI MIKE,WHAT IS THE PROBLEM..THESE OLDER TRUCKS HAD A CHARCOAL CANISTOR THAT IF THE VACUUM VALVE WENT BAD IT WOULD REMOVE FUEL FROM THE CARB AND GET TO A POINT OF FLOODING..BUT TELL ME WHAT IS GOING ON.I KNOW MANY PEOPLE JUST REMOVED THE CANISTORS..TOM

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QUESTION: The truck idles fine drives great up untill high gear then it stops pumping gas to the carb after this happens the truck almost cuts out and goes back to its idle speed and u can tell the fuel isnt pumping as much and after a while it starts pumping perfect again again all the fuel system component are brand new

Answer
HI MIKE, I DO NOT THINK YOU HAVE A PROBLEM WITH THE VENT VALVE. BUT IF YOU WANT JUST REMOVE THE HOSE GOING TO THE FLOAT BOWL AND PLUG IT FOR NOW..OK LET ME ASK YOU THIS THE HOSE FROM THE SENDING UNIT TO THE STEEL GAS LINE BY THE TANK. HAVE YOU CHECKED THIS HOSES AND ALL THE OTHER HOSES TO MAKE SURE THEY ARE OK AND NOT COLLAPSED, THEY MAY LOOK GOOD FROM THE OUTSIDE BUT WHAT YOU ARE TELLING ME IS WHAT SOUNDS LIKE FUEL STARVATION..IF ALL THE LINES LOOK GOOD AND I ALSO WANT YOU TO CK THE FUEL FILTER [I KNOW IT IS NEW] BUT IF IT PICKED SOMETHING UP IN THE LINES THIS COULD CAUSE THIS PROBLEM..SO LETS SAY THE LINES AND FILTER ARE OK,MY NEXT STEP WOULD BE TO CK THE FLOAT LEVEL,THIS MAYBE TO LOW NOT ALLOWING ENOUGH FUEL TO KEEP THIS ENG RUNNING AT HIGHER SPEEDS AND RPM'S..THIS IS A 4 BRL ???  THESE REBUILD CARBURETORS ARE NOT WHAT THAY USED TO BE..ONE LAST THING IS THE CHOKE SPRING SET CORRECT SO IT IS NOT CLOSING THE CHOKE AFTER WARMING UP.THIS WOULD CAUSE FUEL STARVATION AS WELL..LET ME KNOW HOW THIS GOES,GET BACK TO ME..GOOD LUCK,,,TOM