Ask a typical owner what type of inlet air filter he has and you’ll likely get a shoulder shrug. It’s one of those service items that many rely on the maintenance shop to look after.
But we think it’s critical enough to at least know what type of filter is on your engine and that it’s being properly maintained. It’s a required component to check during annual inspection, but we once spotted a paper air filter on a Cessna 210 that was so dirty and deteriorated we wondered if it was ever replaced. Incidentally, that engine needed overhaul long before its new owner planned. Clearly, air filter maintenance is an easy way to help protect the inside of an engine. According to Lycoming, dust or some form of dirt is frequently the principal factor in premature piston ring and cylinder wear.