I was replacing the carburator on my riding mower that has 17.5 Briggs & Stratton intek engine.  I must have tighten the carb studs just a hair too much.   Now I have a vacumm leak causing the mower to surge off and on.  I was going to use a helicoil kit to tap two clean holes for the studs.  As i look closer at the Carb stud, the end that attached to the manifold....I don't recogonize what kind of thread it is.  It is like a wide thread found on wood screws.  see attached pic or a picture of this part via this link Carb Stud for Briggs and Stratton 31R977-0027-G1 engine.  So I don't know if I need a different type of helicoil and or need to take a different approach.  Looking any guidance or suggestions.   Thank you for looking.
	
		
			
		
		
	
			
			
				
			
			
