Hi I have a craftsman mower with the Kohler 149cc engine, I bought it last march and ran great, but about a couple months ago I tried starting it and nothing would happen, besides the motor turning when I pull the chord. Didn't really need it at the time so I dismissed it. Well now I need it lol I changed the sparkplug, oil, checked spark plug wire, dumped old gas out, put fresh in, sprayed a little bit of carb cleaner into carb air filer port (there was some black gunk inside the port, not a lot, but enough.) and made sure the fuel line going from the tank to the carb was clear and not blocked. Like I said before it won't even attempt to start besides when I pull the cord. One time I tilted the mower back slightly and tried starting it and it made a backfire type of sound. That was only once though. Any ideas or tips are appreciated! And no I don't know alot about mowers obviously. That's why I'm asking y'all. Thanks for your time. Also it's the auto start type of mower if that helps. I wish I would of bought one you can prime.