Please see attached picture. Before starting, drain the fuel from both the gas tank and the float bowl.
1. Remove the carb from the engine by loosening the clamp on the intake inlet manifold. Flip carb over and take off the 4 screws holding the float bowl on.
2. Remove the float pin, push it through using a needle or other like tool.
3. Using a flat-blade screwdriver, remove both of the jets circled. Spray carb cleaner through the jets and passages that are circled. The spray should dissolve and remove any blockages caused by old gasoline.
4. Look through both jets. You should see light coming from the end of each one.
For carbs that are gummed up hard we use compressed air @ 120psi to clean the passages. In some cases using compressed air can actually lodge debris in harder than before, so please be aware of the risk before doing so.
Don't worry if a little gas spills out of the carb when you flip it over to get to the float bowl.