the reason I was forced to keep exploring the issue, is that although that old needle-pointed NGK seemed to cure all ills and thing ran like Swiss watch with it initially, it did not last...began sputtering Thursday shortly after starting on front yard ...conked out altogether, and that conk-out and re-start attempt met with half-baked backfire back though carb/air cleaner even..
tried fresh used plug cleaned with wire brush...re-started, ran ok but not perfectly..
engine appears to have some plug-fouling issue...but I'm not sure source of fouling, rich mixture soot or oil and burned oil...or maybe some of both..
I do sort of get a vibe that thing runs a little rich for whatever reason..
