Ensure that the engine has been turned off and that the safety is on before you start. Begin by taking off the main chainsaw’s housing at the rear upper end of the unit with a suitable screw driver. Take off all the top screws and carefully remove the plastic lid before identifying the housing for the air filter unit. Now proceed to take out the filter and hold it upside down over a flat surface. Be careful that no dust of debris falls into the housing at this time as it may cause the replacement filter also to get dirty faster than usual. Now take the filter element – usually paper or foam – and clean it by tapping on the hard surface. If the filter does not get cleaned, it is time for it to be replaced with a new one. Insert the new unit into the filter housing and slot it back home within the unit. Once the filter is securely fastened in place, replace the main lid and screw back the fastenings holding in into place firmly.