I have a Husqvarna 435 that was brought to me with low compression. I took it apart and noticed it had a stuck ring but the piston and cylinder looked otherwise undamaged. I pried the ring off, cleaned the ring groove out and replaced it with a new Caber plus replacing all the seals and using Dirko on the crankcase halves. I got it all back together and gassed it up and it wouldn't run but for about 2 or 3 seconds and then it would die. I taped the throttle wide open and it still wouldn't keep running. I've replaced the spark plug , the fuel is unleaded plus no ethanol, 40:1. Spark looks okay, wondering if I should spring for a new carburetor...I tried adjusting the carb on both screws from about one turn to one and a half, don't know what it's supposed to be set at..