It IS running out of fuel. Why it takes 4 hours to restart I can’t say, but when it boils the fuel out the carb is empty. It takes a bit to get the bowls filled up.
Do a google search on those carbs. It’s not a secret. You keep saying it’s cool, but that’s just WRONG. It can’t be. It may not be 400 degrees, but it’s hot enough to boil the fuel off.
I’ve had it happen at stop lights, waiting for damn train and once, the last straw with this one was a long line of traffic last year for road construction and it quit twice on me.
It’s boiling the fuel out of it.