Hi I have a briggs and stratton 5 HP engine ride on mower that will only start if I poor some fuel down the carby first then it will start fine and run fine but soon as I stop I have to do the same thing to start it again this engine is on a cox late 1960 mower
Any ideas

Do you have the numbers stamped on the blower housing of the motor? Model type code

By adding more fuel, your effectively choking the engine. First see if the choke is operating properly. See if the choke plate closes when it's supposed to.