Cylinder Block Distortion

WARNING: This page is about a different car, the 2013 Infiniti M56. However, it is still accessible from the selected car via links, so may be relevant.

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 ".
If it exceeds the limit, replace cylinder block.

Fig 1: Checking Cylinder Block Distortion

Courtesy of NISSAN NORTH AMERICA, INC.