I believe this, or a very similar, engine is shown in one of the "How it's made" episodes. You can see it on youtube: https://www.youtube.com/watch?v=I3jE-PXV-6

I believe this, or a very similar, engine is shown in one of the "How it's made" episodes. You can see it on youtube: https://www.youtube.com/watch?v=I3jE-PXV-68 https://www.youtube.com/watch?v=I3jE-PXV-68