Re: 2nd motor broke. Was working fine, now makes clanky and metal on metal scratching
Use a screw driver with the plastic end against the bone right in front of your ear. It works like a stethoscope. The find where the noise is coming from. Take it apart, find the offending broken goodies, and repair/replace. I doubt running it wide open for 3 miles broke anything major, especially on a four stroke. I'd bet it's something like the pull start, flywheel, or something non "lethal".