Remove and disassemble the cylinder head. Check for flatness (warping) the sealing surface of the cylinder head using a regular template ruler (metal bar) and a flat feeler gauge (see fig. 3.72).
The maximum permissible non-flatness of the cylinder head is no more than 0.05 mm.
The non-flatness is eliminated by grinding the mating surface of the head at the service station; to do this, it is necessary to check the height of the cylinder head. The nominal height of the cylinder head should be 140.0 mm, the minimum permissible height, after grinding, is not less than 139.7 mm.
A repair cylinder head gasket, which is 0.3 mm thicker than the standard one, must be installed under the cylinder head that has been ground. The repair cylinder head gasket has a marking hole in the rear part (arrow, Fig. 4.52) in the area of the 4th (or 8th) cylinder.
