There should be a small solenoid on the carb input. Take a look at it to make sure its open. If not your shutting the gas off to the carb.
See if its always 4 min that it runs. If so, thats how long it takes to go thru the gas in the bowl.
See if its always 4 min that it runs. If so, thats how long it takes to go thru the gas in the bowl.