[gvthnks]

Dust and grass clippings might get pulled into the flywheel housing and over years build up and plug engine cooling fins and air flow passages. If you suspect that’s occurred, you can remove the sheet metal covers from the engine and debris to restore cooling air flow.

Besides ensuring the carb is squared away, this is critical. With the engine running, you should be able to put your hand in front of each cylinder and feel plenty of airflow coming forward from the flywheel. I know that "plenty" is subjective, but there should be a good volume of air coming through on both sides. If not, then there's a blockage somewhere. This assumes all the original sheet metal covers are in place and directing air over the cooling fins to begin with. If they're not, then the flywheel is throwing cooling air to the sides and not through the cylinder cooling fins it'll run hot anyway. You can use a pressure washer to clean the fins out if they're clogged, but I've seen them so bad that I had to use a thin screwdriver to dig out old grass and mud and oil. Engine ran so much cooler after that.