What you're talking about is fairly dangerous if you aren't familiar enough with engines to answer this yourself. What you should do is put everything in the position it needs to be in to start the machine. Then, pour a little bit of fuel straight into the intake and try to start it, perhaps it's been sitting over the winter and the fuel has gummed up the carb. If the engine gets fuel, it will try to run on that fuel until it dries up. I am not suggesting you do this, but if you want to, do it at your own risk. Remove the top cover of the engine, and disconnect the small wire from the coil that grounds the spark back to the coil instead of allowing it to complete a circuit that allows the engine to run. That one wire is the ground wire, and it will allow the engine to run if it's a broken interlock switch someplace, and then you can narrow down which one it is, but if you remove the small wire, as long as the engine is MECHANICALLY sound, it will run if there is no issue with the fuel delivery system. I have seen may times, the pushrods snapping inside which are what opens and closes the valves. They're designed to break so more expensive components don't. Fuel in the oil, or water in the oil will ALWAYS break the pushrods, so if you have a harbor freight near you, get a cheap compression tester and check the compression of the engine. If it's zero, I'm betting my reputation that the p.rods are to blame. Try my steps; fuel in the intake, disconnect the ground and try to get it running, and then -actually, first thing's first, I would check the oil level, THEN the compression, then the fuel, then the ground wire. Have a nice day/night.
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What you're talking about is fairly dangerous if you aren't familiar enough with engines to answer this yourself. What you should do is put everything in the position it needs to be in to start the machine. Then, pour a little bit of fuel straight into the intake and try to start it, perhaps it's been sitting over the winter and the fuel has gummed up the carb. If the engine gets fuel, it will try to run on that fuel until it dries up. I am not suggesting you do this, but if you want to, do it at your own risk. Remove the top cover of the engine, and disconnect the small wire from the coil that grounds the spark back to the coil instead of allowing it to complete a circuit that allows the engine to run. That one wire is the ground wire, and it will allow the engine to run if it's a broken interlock switch someplace, and then you can narrow down which one it is, but if you remove the small wire, as long as the engine is MECHANICALLY sound, it will run if there is no issue with the fuel delivery system. I have seen may times, the pushrods snapping inside which are what opens and closes the valves. They're designed to break so more expensive components don't. Fuel in the oil, or water in the oil will ALWAYS break the pushrods, so if you have a harbor freight near you, get a cheap compression tester and check the compression of the engine. If it's zero, I'm betting my reputation that the p.rods are to blame. Try my steps; fuel in the intake, disconnect the ground and try to get it running, and then -actually, first thing's first, I would check the oil level, THEN the compression, then the fuel, then the ground wire. Have a nice day/night.