Technician A says spark plugs that have tapered seats require no gasket. Technician B says spark plugs that have flat seats require gaskets. Who is correct?

Question

Quizplus · Accepted Answer

Both technicians are correct. Spark plugs with tapered seats are designed to seal directly against the cylinder head, eliminating the need for a gasket. Spark plugs with flat seats require gaskets to ensure a proper seal.

Technician a Says Spark Plugs That Have Tapered Seats Require