As I was watching the news this morning they reported that today would be a "Code Red" day. This means that the air will be very unhealthy and you should avoid doing certain things. One of those things is running lawn mowers. They seem to make a point of making sure you know not to run mowers for some reason. Recently I had read that all of the outdoor gas powered equipment combined accounts for less than 1% of total air pollution so I decide to log onto the EPA website and verify this. While I was looking for this specific info I ran across this web page. http://www.epa.gov/otaq/rfgnonrd.htm Pay specific attention to the paragraph titled "Enleanment". We are using gas here that has MTBEs in it all of the time, not just in the winter. We have what is commonly called "Boutique" blended gas. Could it be that the EPA is putting so much MTBE addititive in our fuel that our engines are, in fact, leaning out to the point of running too hot. The year before last I had to get a Kawasaki 14 hp engine rebuilt. The blowby was getting out of hand. The mechanic said the engine had overheated. I asked him how that could happen. He said it usually happens when the cooling fins getting clogged up with debris (nope, wasn't that, I keep them clean) or letting the engine idle for a long time on hot days(that doesn't happen either). Does the EPA owe me the price of a rebuild?