First I’m not criticizing your approach. If your enjoying this endeavor, that what its all about. Equations and theories are far above my IQ level. I have to deal with results. My method is to inspect and clean the gear case, fuel system, and ignition, checking for spark. If there are no obvious issues, I try to start the motor. If I cant get one to run, then I get out the ignition tester, compression gauge, multimeter, exct. and try to discover the issue. I don’t disassemble the power head until I’m convinced that is the problem. The parts aren’t available to correctly rebuild one, and as the rings are seated, I feel its best not to disturb them. This is not to say you have made a mistake, its just what works for me. I can tell you that because of the fuel at the time your motor was new, the compression ratio’s in most motors were rarely more than 6 to 1.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.
