Stihl MS 311

• Reduced-Emission Engine Technology - Caring for Nature 

The STIHL Inc. “Caring for Nature” seal identifies its powered products that are more environmentally conscious, producing zero or low exhaust emissions. STIHL Inc. defines “low exhaust emissions” as being cleaner than EPA and/or CARB exhaust emission standards.

• Pre-Separation Air Filtration System 

This time-saving technology boosts the efficiency of the engine’s filter system, doubling the time between air filter cleanings. Air drawn into the engine is first separated via centrifugal force, ejecting the heavier dirt particles before being routed to the air filter. This pre-separation means less dirt to be captured by the air filter, resulting in less frequent cleaning and maintenance.

• Anti-Vibration System 

STIHL has developed a system for minimizing the vibration levels of handheld outdoor power equipment. The STIHL anti-vibration system helps reduce operator fatigue and provides a more comfortable working experience.

• Side-Access Chain Tensioner 

The side-access chain tensioner makes it much more convenient for the user to adjust the saw chain with a bar wrench as opposed to the typical location of the guide bar adjustment screw.

• Decompression Valve 

The decompression valve, also referred to as 'deco' or 'deco valve', vents compression in the cylinder for easier starting. The decompression valve temporarily reduces the compression in the combustion chamber during cranking and helps reduce the effort needed to pull the starter rope. It is opened manually and closes automatically as soon as the engine fires.