Hi all, after an extended search to find out which type of engine I had on an old Poulan PXT22 mower, it took some digging and a Husqvarna rep was finally able to track down that it had a Rato 140 engine, and not a Briggs and Stratton like I originally thought. Does anyone own one of these and how good are they? I have used it since it was left with the house I ended up purchasing. I have done an oil change once a year and it seems to run okay, i havent touched the spark plug or air filter. I have replaced the mower blade last year. Do you all replace mower air filters regularly or not bother? I was thinking of changing out the filter.. but not sure I want to spend 15$ on a new one.. guessing the one it has is about 5-6 years old (might be as old as 9-10 years old) I will be replacing the spark plug this year and putting in some 10w30 oil per their manual. (I have used 5w30 syn HM last year with no issues). Anyone have one of these?