Well, With new engines you normally dont get a flywheel or a clutch with, you get everything else. But then there are some engines that dont include a carb. The problem is that .15 thing might not fit on a .18 engine. The .15 carb wont work on the .18 engine coz an .18 engine needs more air than a .15 carb can give. As for the flywheel, 1st of all you need a flywheel tool.

Ryan.