Air Pressure (or Steam) Engine

Disclaimer: This is my first ever 3D project (I just started learning Cinema 4D) so please be gentle on the critiquing...

I built this design (and had it working) in my high school metal shop a long, long time ago (well not that long ago...) and thought I'd recreate it for you folks. I still have my original one I made somewhere, so when I find it (...in a box in the garage...), I'll post some real pictures of it later. I'm also including my original C4D projects if anyone wants to play with