Guessing doesn't do it!
If you had fuel somehow leaking into the cylinders, removing the spark plugs and examining them would reveal that.
You would also need to check for proper spark... all spark plugs removed. Use either an adjustable gap spark tester, available at any auto parts store... OR... you could use a #2 Phillips screwdriver, having the tip inserted in one of the spark plug boots so that the tip of the screwdriver is entered into the spring clip that normally grabs the spark plug tip, then hold it approximately 7/16" away from the block while cranking the engine.
The spark should jump that 7/16" gap with a strong blue lightning like flame... a real SNAP! The 7/16" gap is important. Using a spark plug to test or a smaller gap is a waste of time.
Look over the stator under the flywheel very closely. If it is cracked and/or dripping a sticky looking substance down on the timer base and power-head... replace it! That sticky looking substance dripping would indicate that at least one of the large coils within that stator has failed which would result in weak and eventually no ignition.
Stators in that flawed meltdown condition may work fairly well when cold BUT when hot, as with a engine just turned off and having all the heat rise up to that stators location... that heat will knock the stator out of action until it cools off again... "MAYBE" as it will fail altogether eventually.
