I have 3-weedeaters (1-Echo GT200R and 2-Craftsman Weedwackers 31cc engines.All 3 have Zama carbs and I have put rebuild kits in all three but I still have excessive amount of fuel leaking from the carburetor throats when trying to start them. I have replaced the fuel lines, checked for binding or crimped lines--checked the gas caps--checked the muffler for excess carbon --adjusted the needle valves out about two turns. The Echo will run at idle with a full choke but will not accelerate to high speed. The two Craftsman will not even start.The two Craftsman trimmers have remote primer bulbs and I have double checked the routing of the lines which seems to be correct. I cannot figure out what is causing the fuel to run out of the carburetor throat.Any help would be appreciated.