Update,
I went to my local lawnmower shop with both engines a couple weeks ago. The chap took a look at the crankshaft of the orange engine with the damaged keyway. He said he has seen worse and it would be salvageable with a longer key. Apparently you can get em' cut to any length. They don't do rebores, but sent me to some performance car shop were they do. They asked for $140!!! (to machine that sucker). But first they need to see the oversized piston, to measure the new diameter. They also said they have seen worse and that a light hone and new rings might do the trick. But it could smoke a bit. Bugger if I am going to spend close to $200 just to get the internals back to spec.
Anyway, all the parts on the orange engine are painted. I will be putting everything back together in the next few days and depending on the weather, shall start her up and see how/if she goes. What this rebuild has taught me, if anything, is that a lot of meticulous effort, time, money, tools and parts are needed to restore a beat-up, run-down, rusty, small, 30+ yr old engine to its former glory. Some people will also mention, that it will never be the same as it was, when it was new. So true.
