In 1991, I bought a STIHL weed trimmer, gasoline powered. It ran famously until 2011, lots of abusive hours, lots of E-10. When it died the piston was simply worn out... hence no compression. I don't know why your Weed Eater died, but you get what you pay for. I bought another STIHL.... cost 10-20% more than a Weed Eater... worth every penny. And, I don't have the option of going battery or electric for this machine. Too much remote work.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.