Sounds like a fuel pump or filter problem.
dirty carb bowl or water in the carb
Sounds like no gas is getting to the carb. Fuel pump maybe.
remove the the bowl on the carb and clean with carb cleaner, be sure to clean the main jet. and the small holes in the bolt that holds the bowl on, if these are plugged the mower will start but not stay running
I am pretty sure that you are going to have to put this vehicle in a garage and have a mechanic look at it
you should stay on your diet for about 6 to 12 months
you need to check the fuel pump and fuel filter if the fuel pump is not working start in the fuse pannel
More info needed, Carb or fuel injected????? Check TPS sensor in FI cars - common issue
By "will not stay cranked", I assume the engine runs and shortly dies. The engine is dying due to either fuel starvation or overflooding. Conditions that would cause this are: clogged fuel filter; fouled/bad spark plug; plug gapped wrong; fuel float not operating correctly; carburetor needs to be reset.
Just as long as you have enough gas to fill the float bowl on the carb is all that is needed to start a bike. It won't stay running long if that is all you have though, maybe 2 minutes.
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Possible buildup in the line from the gas tank to the carb.
either your starter is bad or u have engine problem idiot