I'm at my wits end. Changed my impeller this spring to get ready for the season. Went to change the oil and there was water in the oil. Plugs were gummed up too, black gunk. Read that this can happen when the thermostat sticks open and engine runs cold. Changed thermostat. Haven't been able to get it started tho. I've checked gas and it's getting to the carb. Gas is good. I've pulled the carb and verified all the ports are open, and sprayed everything with carb cleaner. Changed spark plugs. Verified I am getting spark. Cold, each piston has 120psi compression at wide open throttle. Checked lanyard and switch and it looks good, and since I have spark I'm feeling good the switch is functioning. What else is there? It doesn't even pop off ever. You'll get a little sputter here and there, but it barely sounds like it might be firing. Help!