Good day everyone. I need some help with the installation of my hacker 50-16L. I thought I had it in correctly and still think I do, however, when I just ran it up for the first time the prop (with adapter and spinner) flew off. I had the prop mounted using the adapter that squeezes tight over the motor shaft when you tighten the prop. Is this the correct adapter. There is a rear mount adapter included with the motor but I can't seem to figure out how you would mount the motor using this rear adapter. Help would definitely be appreciated. Thanks