Grettings all. I have a Lycoming O-320 B3B that I am going to rebuild. After 10 years in the semi-pro drag racing arena, I have the skills and tools to rebuild the engine. My Lycoming overhaul manual says to use a test club to fire the engine up and test run it. The test club looks like a propeller, so why shouldn't I use a propeller? Thank you for any info.