While you wait for answers, we may have found some information which could help you.
Click here for Briggs Mower StartPetrol or diesel?
Briggs and Stratton SP470?
my briggs and stratton 3.5hp starts up then cuts out straight away?
My Briggs & Stratton 10.5 engine will start but dies after about 15 mins?
McCulloch lawnmower parts removal ?
lawn mower engine hunting?