I purchased this Norvel 074 many years ago and have never run it. Yesterday was it's first run! Had to use heat gun to even turn over. It does not take much heat to free it up. I started with a 6-3 prop. Used Hobbico fuel w/25% nitro. I added a little extra castor oil to the mix. This is the rc version. So choked it to draw fuel to carb and added a few drops into venturi. I flipped the prop for some time and the best I get was a couple pops. Did not want top use a starter for fear of bending the rod. I decided to remove the muffler, now it was acting like it wants to run. Needle 2-1/2 turns out. Still using heat gun and finally it fired up and ran like gang busters. About 20 seconds into the run the prop flew off but engine is now really over speeding so pulled the fuel line loose to stop it! I thought I must have destroyed it, but after reinstalling prop it fired right up and ran great. The prop was on as tight as I could make it without stripping the threads so a little leary about that happening again. It did surge a little on the first run so I"m thinking maybe that caused the prop to fly off. Lucky I found all the pc's. I read some where the bolts that came with Norvel engines have soft threads, so will try to replace with better quality. Anyone else have similar experiences with this engine? Richard