I have not tried to replace the fuel line yet, but i did take it out and blow some carb cleaner through it and replaced. The fuel lines can only go one way. One is slightly bigger than the other. And i used fresh gas when i poured it in. I had bought it about 3 days earlier. The only thing that i done wrong is i mixed a bottle that would make it 50:1 i stead of the weedeater recommended 40:1. But from reading other posts, that wouldnt prevent it from running. I will try the filter. Is there anything else i can try? Is there any chance the ignition coil is too far away from the flywheel? Would that cause it to bogg down any?