STIHL air filter system: longer life and better performance

Why your tool needs an air filter

When an engine is running it continuously takes in air. This air passes through a filter before it reaches the engine, in order to guarantee that the combustion process runs as smoothly as possible, and to keep wear and tear to a minimum. This is to filter out unwanted particles such as concrete dust, wood splinters and other fine debris from the surrounding air and to stop them from entering the engine, where they can easily cause damage. That’s why many STIHL chainsaws and all STIHL cut-off machines include an innovative long-life air filter system. 

STIHL air filter in chainsaws: extended service life

Most STIHL chainsaws have an innovative long-life air filter system with routing to take the strain off the downstream filter elements. It works like this: 

• First, the intake air is set in motion; this flushes out the larger and heavier particles in the air. This pre-filtered air is conveyed along the routing channel to the air filter in your STIHL power tool engine.
• The intake air is then passed through the high-capacity air filter, so the air delivered to the engine via the carburettor or STIHL injection system is clean. In many of our power tools, this air filter is interchangeable, so the filter material can be adapted to suit the conditions; polyamide filters for cold weather, for example, or our high-performance, innovative HD2 air filter made from polyethylene filter material. The HD2 air filter pores are up to 70% smaller than those in fleece and polyamide filters, meaning it can effectively filter even the finest dust from the intake air. The HD2 air filter is also oil- and water-repellent, as well as being equipped with a highly effective seal that prevents unfiltered air from getting into the engine, thereby prolonging its service life. What’s more, HD2 air filters can be easily cleaned and reused multiple times: just spray the removed filter with STIHL Varioclean, leave the detergent to take effect briefly, then rinse and dry the air filter before reinstalling it. 

STIHL professional tip: You can upgrade your standard air filter to the HD2 air filter. It comes in three variants to fit different chainsaw models 

Stihl air filter system in cut-off machines: cyclone-strength power

STIHL cut-off machines all have a long-life air filter system that includes cyclone routing, a paper filter, and a fine dust filter. The innovative cyclone routing system means no need for daily filter cleaning and a much longer filter service life. This is how the air filter system works in detail: 

• In the first phase, the cyclone routing extracts around 80% of the dust particles in the intake air. Unlike conventional systems, these particles do not collect in the air filter, but are expelled back into the environment together with the cooling air. 
• Next, the paper filter removes particles from the air that has passed through the cyclone routing system. This efficient routing helps extend the service life.
• After the paper filter, the fine dust filter traps virtually all of even the finest dust particles. 

Benefits of the STIHL air filter system

Long-life air filter systems offer a whole host of advantages. 

• Methodical cleaning: routing reduces wear and tear on downstream filters. 
• Better filtering effect: the load is shifted away from the high-capacity air filter. 
• Longer filter service life: service intervals for cleaning and replacing the air filter are significantly extended. These intervals can vary depending on the filter material and use. 
• Low-maintenance and user-friendly: STIHL long-life air filter systems do not require any special care .
• Easy maintenance: cleaning the air filter on a chainsaw is quite straightforward. Details of the process can be found in your operating instructions. 

Summary: STIHL air filter system 

• An air filter removes unwanted particles from the air taken in by the engine
• STIHL has developed a range of innovative air filters that are optimised according to the application. Your specialist STIHL dealer will be happy to advise.
• STIHL air filters guarantee a long service life for the engine, prevent premature wear on pistons and cylinders, and stop contamination of the fuel mix