If the bolt stuck in the engine is protruding from the surface, tightly clamp pliers onto the bolt, and try turning it out. If the bolt doesn't come out, use a propane torch to heat the bolt and surrounding metal surface until they turn a dull red color. Don't overheat the bolt, as you may damage the engine or surrounding parts. Try turning the bolt once again using the pliers.Continue Reading
If the bolt still doesn't come out, grind or file the protruding part until it's aligned with the surrounding metal surface. Use a drill bit or center punch to locate the center of the bolt's shaft, and create a starter hole for the drill. With the aid of a left-hand drill set, drill through the bolt shaft. Use a drill bit that is smaller than the shaft.
If the drill bit doesn't unscrew the bolt shaft, use a larger drill bit. Repeat until you're left with remnants of the bolt's threads in the hole. Use a dental pick or threading tap to remove the remnants. If the threads were damaged in the process, tap new and larger threads into the hole, and find a larger bolt to fit there. Alternatively, fit a HeliCoil in the hole you tapped.Learn more about Engine