One of the things that tend to get ignored on small engines is the air filter. We forget about them in our cars as well, but your small engine filter is working in conditions that would probably make your car cry. Motorcycles, mowers and other power equipment are used in dusty, hot conditions. Over time ignoring your filter can lead to some pretty serious problems like hard starting, poor performance, fouled spark plugs and even engine failure.
As a general rule, outdoor power equipment (like lawn mowers) should get a new filter element every year. If you are using your equipment in dusty, harsh conditions it should be changed more often. On dirt-bikes, if you are riding here in Sunny Central Washington, you may need to service your filter after every ride in the summer. If you are riding in conditions that are not dusty you can go longer. But you should inspect your filter after each ride and service it sooner rather than later. Don't wait for it to turn into a blob of dirt.
Depending on the equipment there are different types of filters and ways to service those filters. Many pieces of outdoor equipment use a double filter system; a pre-filter and a paper air filter element. The pre-filter is typically made of foam or a combination of foam and mesh. In most cases these filters can be blown out with air or even better washed with soap and water. If you choose to wash your pre-filter make sure it is completely dry before installing back on your machine. The paper filter element can be serviced if it is only slightly dirty. Simply blow it out with compressed air. However, be careful; these filters are made of paper and are easily damaged with high pressure air. If the filter is very dirty, oil fouled are starting to look gray, replace it. When in doubt throw it out. Just be sure to replace it before use. Don't be tempted to run your engine without an air filter.
Off-road motorcycles and ATV's often use a two stage oiled foam filter. These filters are meant to be washed and oiled regularly. If you have never washed one there is much too it, but there is more than one method. The safest is to purchase a commercial foam air filter detergent, always follow the directions on the packaging. But to give you a general idea, wash to the filter with detergent, rinse thoroughly, allow to dry completely (overnight in a warm place) and apply filter oil. The "other" method which is cheaper, but requires a bit more caution is to wash the filter first in solvent and then in hot soapy water. Dawn liquid dish soap or a similar product works well. Rinse completely and then allow to dry over night. If you go the solvent route it's important to wash the solvent out as quickly as possible. Over time the solvent will start breaking down the glue and even the foam of the filter.
When it comes to oil there are lots of products on the market, just be sure it is the appropriate oil for your filter. K&N oil for example is designed for a specific type of filter and should not be used on a foam filter. When you are applying the oil, be sure to saturate the filter and squeeze out the excess. Some instructions will say to submerge the filter in oil; you can do that but it requires allot of oil, is messy and not really needed. Make sure to apply the oil extra thick on the sealing ring, or use filter grease to insure a complete seal.
If you are thinking of skipping the oil and just running the foam filter dry, stop right there. If you choose to go that route the filter will only catch the large particles and allow the fine dust to pass right through and into your engine. We have done some very expensive repairs for customers who have gone this direction.
If you have a K&N filter or similar product it's recommended that you use K&N filter cleaner and oil. Pleated filters are great but require an extra measure of care when cleaning and oiling. Always follow the manufactures instructions.
Last but not least, always remember to wear appropriate gloves and eye protection and avoid skin contact with cleaning chemicals, solvents and oils. Those warnings on the label should be taken seriously, even outside the state of California!
Keeping your air filter clean can be the difference between a good day and a bad day with your equipment. It's one of those maintenance tasks that don't require much mechanical expertise or time. But as always, if you don't feel comfortable taking care of it yourself or just don't want to do it, give us a call and let us take care of it.