I need more info. Does it crank and run and then die? Runs how long? In what ambient temps? How does it run? Rough, smooth? How does it die? Sudden engine stop, or sputter and then stop? Is it running at speed when it dies or at idle. When running, how does it respond to opening the throttle? How does the exhaust smell as it dies? gassy or acrid?

How long did the old fuel sit in the tank? How does the tank smell at the filler neck? Have you drained any fuel and was there water in it?

Not responsible for advice not taken...