Now that I have the motor all apart ... I have to say I'm surprised these things last as long as they do! There was no oil in it, no grease - nothing. There was just a thin oil film on the internal parts, and not much of that. Rust is starting to form on the crank counterweights. Then there were several machining burrs left behind. Maybe mine missed inspection, but you gotta wonder...
I was hoping to get a motor with the spark plug in the center of the head because of the way I'm going to set up the steam inlet, but the plug on this one is at an angle. So ... I decided to make a new head.
I cut down the original to use as a pattern, sculpted over it with Sculpy and baked it. I added an old timey "H" and the word, "steam" just for fun. Tomorrow I'll use it as a plug in a sand mold and then cast a new one in my backyard foundry.
Clay leaves a lot to be desired, so we'll see how it looks when I get it cleaned up after casting.