My first move was to see if it was getting gas, I theorized that perhaps the fuel tank wasn't venting properly, which would result in fuel being unable to reach the carburetor. However after a few minutes of running the motor with the gas cap open, it still died. This ruled out a gas tank venting problem, however it still could be caused by a partially clogged fuel filter restricting the flow of gas to the carburetor. Unfortunately after cleaning the fuel filter with compressed air, the motor would still die.
My next action was to check the air filter, (if not enough air gets though the filter the motor will run rich, and die) but it seemed ok, and the motor still died when it was removed. Both of these tests showed that the problem was either in the carburetor, or was an electrical ignition malfunction preventing spark.
Testing whether the motor is receiving spark is easy, you simply remove the spark plug and hold it against a metal part, while turning over the motor. If you see a strong blue ark come from the plug, all is usually good, if you don't, there's no spark. Obviously the motor receives spark initially, otherwise the motor would never start, I wanted to see if the the engine was dying once hot because of a lack of spark. I ran the motor until it died, pulled the plug, and sure enough it didn't spark. So the problem was electrical. The series of components that create and time the spark are called the ignition system, and one or more of these parts was failing after a few minutes of run time.
If the spark is weak when outside the cylinder, it may actually be unable to spark at all, under the extreme pressure of a cylinder.
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