Review on Helicoil 5546 8 Metric Coarse Thread by Daniel Elgee

I have to admit I was nervous installing this product. I had to replace the threads on two cylinder bolts on the engine. I was worried about drilling the hole a little crooked and then the studs wouldn't line up. If I screwed up, I didn't have a "plan B". For all my misgivings, the first one lasted @ 45 minutes. After the first, the second lasted about 10 minutes. It's a lot easier than I imagined. Follow the instructions and it will work smoothly. One point though. When drilling a hole for a spiral, the taper at the end of the drill must be taken into account. When screwing in a spiral coil, it stops when it touches the cone. Make sure the full diameter drill hole is deep enough to allow the bit to go all the way. It's really a very simple process that does its job very well.