I have an 80 GK Saito FS that was mounted on the side in one of my planes, in a bad landing the gear came off, the muffler was hit and the extension pipe was torn out of the threads in the head, it does thread in the head somewhat but virbrates loose very easily. The cost of a new head almost makes more sense to part out the engine and buy a new one. Anyone ever had any luck repairing the stripped out threads? I tried some JB weld but that doesn't work, can it be repaired?