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String trimmer runs rough
Brand:Stihl
Model:FS 40
Product:String Trimmer
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String Trimmer Runs Rough? String Trimmer Troubleshooting
02:25
Common solutions for: String trimmer runs rough
01 - Spark Plug
Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.
Genuine Part
Easy Fix
Genuine Part
Easy Fix
Common
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