This thermo-acoustic hot air engine has 2 cylinders & the flywheel is between the 2 cylinders. It is a powered by an alcohol burner. Firstly, light the wick, & then make sure you give it a good minute or so to heat up as well. Try to give a little push to the flywheel which is strong enough to coast the parts for several cycles. After a few seconds the flywheel will perform a full revolution and continuing running on its own. The engine can performs in 2 directions, clockwise & also counterclockwise.