Buzzsaw sound?

Has anyone heard a buzzsaw sound before when trying to start their car? I changed over the intake and carb and was testing out the new firing. I had a couple of dry fires, then got it running pretty smoothly. Was running pretty hot right away so I shut it down. Started it a few minutes later and then a buzzsaw sound.

Oil is good, coolant is good, I didn't know if this was a weak starter sound, a weak battery, or something like the engine eating itself
Author: ideologist