Small Engines (Lawn Mowers, etc.): craftsman 917.2766813, craftsman 917, air filter

Question
my tractor starts %26 runs about 3 mins then quits and won't restart until about 10min later i changed oil, air filter %26 plug .everything on the carb looks normal.< springs etc. > where or what should i do now ? has a Briggs 31p977-0635-e1 motor and i believe a nikki carb       thank you

Answer
Does it have spark when it dies?  When it dies, can you remove the air filter and spray starting fluid in the carburetor to see if it will start?

How old is the mower?  Have the valves ever been serviced?  Do you have a cylinder leak down tester?

Let me know.
Eric