I always hear about fuel problems. I bought a few used machines and to say the dirt in the fuel was the biggest problem. Not sure how it works? Do you sabotage a engine with dirt so it will not run right? I left my 272 Husqvarna with fuel in it for 10 years it was really low on purpose I left it set. Now I added about double what fuel was in there. Started in 4 pulls ran like a champ. What I did have over the years a 394 Husqvarna the fuel system so full of fine dirt I cleaned the tank for a while had kt 17 Kohler I bought a garden tractor that would fill the crankcase with fuel and hydro lock the engine. I notice it had brand new carburetor on it when I cleaned the tank, I found the trouble. Just be careful when you add fuel. Or just blame the fuel and I will not hear it anymore