Cleaning Your Stihl

• The air filter and the area around it must be cleaned after every use. The pad or foam filter will quickly start to get clogged and your engine will start to suffocate. On the other end, the muffler and spark arrestor screen require cleaning after every 20 to 30 hours of operation in order to let hot gasses escape. Clean these parts with a rag, an old toothbrush and a mild cleaning agent, like dish soap.
  
  

Replace Filters and Plugs

• When the air filter starts to get past the point of cleaning, replace it. This will drastically improve engine performance. The spark arrestor screen also should be replaced if you can't clean it. The spark plug will also get corroded and dirty over time, so check it periodically, about every two weeks, to ensure it will fire properly.
  
  

Bar and Chain Maintenance

• Clean and sharpen your chain and bar after every use. This will ensure you only cut with a sharp chain, greatly reducing the risk of injury. The guide bar can be cleaned with a rag and flipped over to get even wear on the bar. The inside of the bar's slots can get clogged with old bar oil, so it will also require regular cleaning. The edges of the bar will also develop burrs on the edge that will need to be flat-filed very week or so.
  
  

Lubrication

• The nose sprocket on the tip of the bar should be greased every couple of weeks, depending on your use. The clutch assembly also uses a needle cage bearing, which needs lubricating every week. Underneath the clutch are the worm and drive spring, which require lubrication every 30 to 40 hours of use. If the engine isn't lubricated, parts will start to heat up, causing serious engine failure.
  
  

Carburetor Adjustment

• The carburetor has three screws, which should be adjusted regularly to optimize the amount of air and gas flowing through the engine. When you begin noticing performance problems, such as slow acceleration or stalling, you should readjust the carburetor screws.
  
  

Basic Repairs

• Fuel filters and fuel lines should be replaced at least once each season -- more, depending on your operating conditions. Fuel tanks also require bi-weekly cleaning to prevent dirt and sawdust from entering the fuel system and plugging it up. Sprockets and clutch drums should be checked periodically for wear. Sprockets should be replaced every two chains and clutch drums every four. These simple parts will ensure the engine will last as long as possible.