HK advertises that all of these engines have been run for 7 minutes. If that were true they would have seen that the prop wobbles. Don't tell me something if it isn't true. I don't know what the problem is, all I know is the prop has a wobble to it. I'm talking by turning it over by hand. Lords know what would happen if I started the engine and got it up to 6,000 rpms. but you know what, I am going to start the engine and see what happens. I will take it out of the plane because it is worth more than the engine.