Cylinder Block Distortion

Using a scraper, remove gasket on the cylinder block surface, and also remove engine oil, scale, carbon, or other contamination.
CAUTION: Be careful not to allow gasket flakes to enter engine oil or engine coolant passages.
Measure the distortion on the cylinder block upper face at some different points in six directions (C), (D), (E), (F), (G), and (H) with a straightedge (A) and a feeler gauge (B).
Limit : Refer to "CYLINDER BLOCK ".

Fig 1: Measuring Distortion Of Cylinder Block Upper Face
Courtesy of NISSAN MOTOR CO., U.S.A.
If it exceeds the limit, replace cylinder block.