If you work in a machine shop you should have everything available to you. I would chase all the threads first. Just to see how it works. (Most likely not). To fix the right way. Use something that will fit in hole to be repaired to check depth Put paint mark on drill th hold same depth. Make up a block to keep drill square. Your dill and tap will be oversize. Not sure what the drill is but Tap comes with helicoil. Use a tapping block to keep your tap square. Be sure to use oil on the tap. Or Your next move is a keensert. Use helicoil tool to install. Repaired ready to rock and roll.