I was so impressed with the way my new reversing valve worked on my double wobbler that I have to share it. This is by no means an original design, as I was helped by a couple of forum members to figure out exactly how this kind of valve would work. About the only difference in a valve like this working on steam as opposed to air engines, is that the air inlet tubes should be threaded into the main valve block and not just Loctited as I have shown. I know for sure that this reversing valve will work on a wobbler (oscillating) engine. I'm not sure if it will work on a conventionally valved engine like the Cretors Popcorn engine or not.