1950 Firestone 7.5hp failure

Motor failure from overheating and/or lack of lubrication to vital parts. Gas/oil mixture used was 16:1 with Recreational gas and TCW-3 marine oil, a common mixture for smaller motors pre 1960. I made sure I was getting a decent amount of water pumping the entire time by periodically checking the temperature of the exiting water; water exiting the motor was around 120 degrees. I suspect a blockage somewhere, perhaps around the the cylinder head area. At some point I will do an engine teardown and look for the issue. I've had a few other motors of the hundreds that I've repaired that failed in a similar way unfortunately.