Diesel impact pile driver. 0:31 video.
https://www.youtube.com/watch?v=YS0i7OZE3R4
Previously:
https://www.homemadetools.net/forum/...178#post115841
https://www.homemadetools.net/forum/...4104#post79337
https://www.homemadetools.net/forum/...411#post135413
https://www.homemadetools.net/forum/...856#post140403
https://www.homemadetools.net/forum/...011#post153164