Runs great for many hours. Farmer ran it out of gas, and wouldn't restart, even pulling it only made it burp.
I'm also tracking on a loose component like a cam or whatever that is slipping.
It seemed to be exactly one "tower" out. Lined up flywheel mark at TDC #1, and the rotor was way off. Moved the wires clockwise one position, i.e. advanced 90 degrees, and runs great.
I doubt sabotage. Will investigate how these things are actually built and look at slipping components.