I’ve researched “Fuel Tank Manufacture”.
After researching, I can’t place the manufacturing machine. It is still not available to build.
Hovering with the Mouse over “Fuel Tank Manufacture” in the Tech Tree, it shows “(New Slot) Make Flywheel”.
I can now build the Flywheel manufacture.
I think the fuel tank manufacture research is broken because of this at the moment.
If you need screenshots or savegames, I can provide this.