My prop is perfectly balanced and so is my spinner what do think about the metal ring that is part of the block coming off and messing up the threads on spark plug . I have had this happen twice the first time the waranty people said that i cross threadded the plug and i did not but i still had it fixed and i had them install the plug for me this time. I have burned less than a gallon of fuel and the same thing happend so obviously i did not cross thread it . I think maybe there is a problem with the design