I have that 550 ex with auto choke and the new plastic carb. It would not start after a few pulls. So I pulled the spark plug and put some gas in the cylinder and tried that. It fired up but quit running after gas ran out. So I did all the diagnostics. I followed the fuel line from tank to carb to make sure fuel was getting to it. That was ok. So I took the carb out and took it apart to check for dirt and it looked clean but I made sure all the little holes were clear and put it back together tried it again and it fired but just won't stay running. So with the auto choke is there an adjustment that may be out of whack or is the throttle/governor off a little? I don't know why I am having this problem because I ran the mower last fall and after I was done I ran the mower until the tank was empty and the mower shut off. Any ideas? Thanks, Bill
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