@BGrow76 I pulled them all one at a time looking for pieces of impeller. I also found a goose feather in the hose from the lake to the strainer.
I hooked the boat up to the hose. Pored coolant in the degas bottle until it wouldn’t drain into the system by itself. With degas bottle about half full, started the boat and checked water strainer. My 196 has the degas bottle at the back of the engine, so I tried to make that the highest point in the system, added coolant until level in the degas bottle stayed consistent. I’m not sure this is the correct method. There may still be an air bubble in there, but it’s running 165-170 as it did previously.