I use GumBuster to clean the carburetors. The kit by cleancarburetor.com doesn't require the carburetor removed from the engine and taken a part to clean. The valve installed on the bottom of the carb gives access to all fuel and air jets. 20 minutes soak time to dissolve the gum. After the 20 minutes the pressure from inside the can pushes out all the dissolved gum from inside the jets. In average 98 snowblowers out of 100 snowblowers were fully recovered with GumBuster kit.