When maintaining the air filter, carefully check the color and contrast of the filter paper on the inside and outside of the paper filter element. The outer surface of the used filter element in contact with the atmosphere is gray-black due to dust deposition; However, the inner surface of the filter paper facing the air inlet should still present the natural color. If the dust on the outer surface of the filter element is removed and the original color of the filter paper can be exposed, the filter element can continue to be used.

How to clean the air filter?
1. Loosen the filter catch, remove the nut fixing the filter element, remove the cover and pull out the filter element. Take out the filter element and pay attention to prevent impurities from falling into the carburetor. Wipe the inside and outside of the air cleaner housing with a rag dipped with gasoline.
2. Start from the inside of the filter element and blow the dust on the inside and outside of the filter element evenly from top to bottom along the bevel direction. If there is no compressed air, gently tap the filter element with the handle of a screwdriver, and then brush the external dirt with a brush.
3. Check and clean the dry filter element. Turn on the light and put it inside the filter element to observe whether there is any damage, small hole or thinning part from the outside, and check whether the rubber gasket is damaged. In case of any abnormality, replace the filter element and gasket.
4. Replace the air filter element. Replace according to the regulations of each model. When replacing the filter element, pay attention to check whether the new filter element is damaged and whether the gasket is damaged. If any defect is found, it should be matched.