Pop Pop Boat Engine — Dry dock testing
This shows a common ‘Pop Pop Boat’ engine being tested out of the water. It shows how the water in the engine moves up and down both exhaust straws.
This is the Blade Attila video where he uses the motion of the engine diaphram to move a ‘whale tail’ at the back of his boat: https://www.youtube.com/watch?v=xsuIT1JyZn0&t=143s
