This isn't a question, but just a comment to help someone who may be having this problem. I have and OS .40 LA and it ran well for me the first couple of times I fired it up. About the third time, all of a sudden the prop nut and spinner flew off as soon as I put the starter to it. I did it over and over again. Tightened the nut as hard as I could, with the same result. Come to find out I was choking the engine too much and it caused too much fuel in the cylinder, plus wetting the glow plug and causing so much pressure in the engine, that it would not turn over, causing the prop to spin off. Hadn't ever heard of this happening, but maybe it's just a rookie mistake. Just my $.02.