This was an attempt at making a fully working radial engine. The problem is that radial engines have an odd number of cylinders and this is very difficult to do with K'Nex without cutting up the parts, which i don't like doing. It was reasonably successful in that it spun over as it should and the cams worked and operated the push rods and rockers.
The slideshow on the right gives a small amount of information that may guide you in building this model.