indeed, I have some propulsion systems in the belowdeck parts thread
here
I could use some input though, so if you draw engine systems please send them to me and I will check them for you and put them in the thread. an separate engine parts sheet would belong there, and I am working on one in the same style as my (yet unreleased) main sheets, so it would maybe be better to just sent me the drawn parts.
especially diesels, waterjets, azipods, nuclear reactors and the older gas turbine types are wanted by me. also, diesel/gasturbine generators could be useful.
note that many manufacturers give the exact sizes of their recent models, sometimes even with downloadable 3D models. these are perfect for building references like these. older types are harder, as the reference is 'historic'.