What is the purpose of using a thickness gauge and straight edge on a cylinder block?

Using a thickness gauge and straight edge on a cylinder block primarily serves to check for warpage. Warpage refers to the distortion or bending of the cylinder block that can occur due to factors like overheating or improper installation. When a cylinder block is warped, it can lead to issues such as poor sealing, ineffective combustion, and can compromise the performance of the engine overall.

The straight edge allows technicians to measure any deviations from a flat surface across the length of the block, while the thickness gauge provides precise measurements of any gaps or inconsistencies in the block's surface. This measurement is crucial because even minor warpage can affect gasket sealing and lead to engine failure if not corrected.

In contrast, while cylinder bore depth measurements and inspections for cracks are important, they are not the primary function of a thickness gauge and straight edge. Similarly, assessing oil leakage is related to surface integrity but does not specifically require these tools for evaluation.