I just came back here to post same info. Thank you though for catching that.
I think the engine blew up today. The rpms were really high, I don't know why. I fiddled with the linkage below the carb, could manually get it to lower rpm but it wouldn't stay. I had a few minutes left to mow. Finished and drove over to the garage. Engine popped really loud, stopped and smoke came out, mostly from gas tank side. The engine spins very freely like there is no compression. Oil level to FULL. When spinning engine the pulley underneath the deck does spin as well. My guess is blown piston or valve head? Ugh.
I've got a hard decision to make. Replace engine or buy new mower.
I've nursed this 30 yr old mower along for 15 yrs. Replaced drive axle, chain roller. Steering & suspension bushings. Steering gear. Had to make or mend some worn parts. One of the front wheel axle w "control arm". Body & seat support. Made a new shifter lever. Replaced spindle.