On mine I tried spray carb cleaner, soak carb cleaner and air. After 3 times, I bought a cheapo Harbor Freight Ultrasonic cleaner. Disassembled, put Simple Green in the Ultrasonic Cleaner and ran it til I thought the cleaner would overheat and die. Put it back together and it's been running strong for 3 years now. Those holes in the carb are tiny...
Good luck.