I am thinking you have the 20hp kohler.
first pull the fuel bowl and check to see if the float valve is stuck and not allowing fuel to enter the carb.
Second check your wiring, some of those units have a fuel cut off solenoid on the carb and any tripped safety switch will make it shut off.
always make sure your safety interlock switches are working.
Those engines have a bundle of wires that come very close to the exhaust and tend to melt with the high temperatures.