my line trimmer starts runs but then stops after 20 seconds .approx. Has clean fuel,filter, think maybe there is a problem with the fuel line or tank not sure am i on the right track?
Mine did the same, it was a perished fuel line. Take the plastic cover off and give the fuel lines a wiggle. In my case they simply broke off in my hand (perished lines let air in/fuel out). They are easy to replace, and should cost only a couple of dollars.