I found the issue. It only went to 1/2 throttle due to the mechanism that prevents full throttle when in neutral.
A part of the linkage connecting the
gear selection to the throttle linkage came loose.
A search online provided the clue.
Then it was 45 minutes actually finding it on my
engine, figuring out how it was supposed to connect, and then trying to get it back together when I could barely sort of reach it with a screwdriver and needle nose pliers.
But it’s running again! And when I first lifted the cowling I found a loose nut laying inside that holds the
fuel filter. So that was another plus.