If the clearance between the stem and the valve guide is too large, the valve guide must be replaced.
After pressing out the guide bushings, expand the hole for the bushing to the required diameter.
Attention: Bushings are replaced with enlarged oversized bushings. Before installing the bushings, they must be kept in engine oil for at least three hours.
New bushings (1) are driven in from the top side of the cylinder head with the help of mandrels, maintaining a certain size (A).
After pressing the guide bushings, it is necessary to bring their inner diameters to the nominal size using reamers.