After 2 horrible Craftsman Eager 1 walkbehinds, I started dumpster diving for my so called lawn OPE. In 25 yrs I have worked up to a '77 IH sitdown and a '93 Toro RWD 3 speed with a Suzuki 4 stroke. Since I have freed up the choke flap, it lives up to the GTS. I have only had to drain the fuel out of it when I left it out in the rain. OOps. They both have shut offs and I run the carbs dry after every use. For smell and for my own sense, I dose every tank of e 10 with a splash of MMO. Following this regimen, my carb troubles have mostly ended. I used to use a lot of Berryman's Chem-Tool on the Tecumseh snowblower engines. It is a solvent that works sometimes by adding it to the gas. I have used it on my weed wacker and it had no instantaneous affect. I put it away for a week. As I was carrying it to my bench to tear down the carb, I pulled the starter and it lit right off.