Review on 💡 Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit: The Ultimate Solution for Thread Repair by Joshua Castillo

I have a lawnmower to ride with a house I just bought and the exhaust manifold and muffler just hung on the cylinder head. One of the exhaust manifold bolts was stripped and needed to be drilled out, the other bolt was removed but the threads were destroyed by the previous owner installing the wrong bolt in the hole. I was looking for alternatives to removing the head for drilling and tapping at a mechanical shop and found this handy kit. It was very easy. The tap indicated the drill size required, 21/64 inch, which I had on hand. Drilling through the aluminum head was easy and threading was easy. The faucet was very sharp and cut right into the aluminum. I was nervous it would go in crooked, but the cone at the top of the faucet helped ease my anxiety. I did a half turn, then stepped back a little, blew compressed air into the hold to force the chips out, then repeated until I got to the bottom of the hole. The faucet was relatively easy to unscrew. After blowing compressed air through the freshly cut hole to remove the aluminum chips, the thread insert was screwed in directly by hand using the tool provided. The total time for both holes was approx. 15 minutes. The only criticism is the notch at the end of the thread insert not "notched" enough that the shank comes loose easily at the end. It took a few hits and eventually pulled in there with a tiny needle nose to finally get it. For this reason I am deducting a star. Overall I will definitely buy another set if I need them in a different size. Huge money savings compared to taking the head to the machine shop for trimming.