It was just on the news that propane will be the future fuel source for lawn mowers. According to WISN 12 news, the government will start checking emissions in small engines in 4 years. It costs $800 to convert and the engine will burn cleaner, use less fuel, more efficient and last longer. When gas was at $3.00 per gallon, propane was a little over $1.50 (according to news station). You can convert ANY gas lawn mower over to propane. Sound good?