Start by replacing the spark plug, fuel filter and air cleaner (believe they make a kit containing these parts for this purpose.)
Also you need to pull the muffler and clean the spark arrester. My suspicion is its partically clogged. Just pull it and either replace with new (if bad) or hit it with a small propane torch (or hold it over a gas burner on your kitchen stove using needle nose pliers) to burn off the gunk.
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Start by replacing the spark plug, fuel filter and air cleaner (believe they make a kit containing these parts for this purpose.)
Also you need to pull the muffler and clean the spark arrester. My suspicion is its partically clogged. Just pull it and either replace with new (if bad) or hit it with a small propane torch (or hold it over a gas burner on your kitchen stove using needle nose pliers) to burn off the gunk.