Thanks for the info, especially the thread with pics! This being a parts motor, I removed then handle, released the torsion spring tension, and took the starter and the cam follower thingy off. No problem after that except the ugliness in the float bowl. I’m beginning to think this motor may have been fed a load of water via the fuel tank.
More generally: With things opened up there was no difficulty in unsticking the motor–some spray lube and gentle tapping on the piston heads did it. The Cylinder walls look OK, though I’m sure the rings are stuck. It it was a plain bearing motor I’d think it might be run. But it seems there is very little chance the needle bearings and their races aren’t rusted, such that running would result in self-destruction. Anybody disagree, and think a full disassembly worthwhile?
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