yes, you're right. In hindsight, it could have probably been preventd if I had checked the prop bolts for tightness. I've been running the 40, 50, and 100 ever since they were produced and aavailble here in Germany and have never found a loose bolt. So as you say, I'll be sure to check them after every run. We use spring washers over here, I guess those are the equivalent of lock washers. Most loctite sold over here is Blue- red is very hard to find. What's the basic difference between red and blue loctite? Is red more permanent or...?
Thanks for the hints and ideas. Still waiting for my engine to come back and see what the experts say.