This is often caused by one of the carburetor's gas-regulating jets being clogged. When you remove the bottom cover of the carburetor, you will see two "towers," a big and a smaller one, each having screw-in brass fittings called jets. When the smaller one is clogged the engine will run, but not idle. Take both jets out by unscrewing them. Using Walmart's carburetor cleaner spray, clean both both until you can see light through their openings, then reassemble the carb.
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This is often caused by one of the carburetor's gas-regulating jets being clogged. When you remove the bottom cover of the carburetor, you will see two "towers," a big and a smaller one, each having screw-in brass fittings called jets. When the smaller one is clogged the engine will run, but not idle. Take both jets out by unscrewing them. Using Walmart's carburetor cleaner spray, clean both both until you can see light through their openings, then reassemble the carb.