Pop-pop engine (part 2)

Continuation of the last video, showing how to make a small tin boat and an alcohol lamp. The engine is difficult to make but runs very well and has high resistance to heat and pressure. High temperature silicone works great here, it's defined to temperatures until 250°C but as long as the water keeps flowing, the engine temperature doesn't even come close to that. I tried to make several other types of engines, but these engines never worked properly: either they were unstable, or they displaced little water, or they exploded... You may have noticed that in the previous video the motor was very silent, but in this video the motor makes the characteristic "pop-pop" noise. I don't know why this happened, maybe it's the stronger heat source, or the boat moving, or the water temperature... I don't know.