Abstract: The pulling tool has a pulling head for gripping an insert, such as an ene valve seat or a pre-combustion chamber, and for pulling it out of a recess. A gripping mechanism for an annular insert, such as a valve seat, may grip the insert by its inner edges. Such a gripping mechanism includes a shaft that slides freely through a bore in the body in a direction parallel to the body. At the end of the shaft is a cone, which cooperates with at least two toothed claws. The toothed claws may be pivotally mounted on a lower extension of the body or may be integrally formed with one another as a collet and flex radially outwardly. The body may have a lever that, when depressed, lifts the shaft, pulling up on the cone, causing the claws to move outward, and causing teeth to penetrate the metal of the insert on its inner diameter to lock into the insert. A gripping mechanism for an insert having a central or eccentric opening, such as a pre-combustion chamber, may have a pivoting claw arm with a tooth on one end.