While you wait for answers, we may have found some information which could help you.
Click here for Lawn Mower Briggs & Stratton Pull StarterExcessive Compression?
Briggs and Stratton SP470?
Just overhauled 16 hp Briggs ans Stratton engine ?
what causes my Briggs and Statton petrol mower to hunt ?
How to fix a problem with briggs&stratton hp407engine?
b/s lawn mower small engine?