Which method is NOT used for repairing a cracked engine block?

The method that is not used for repairing a cracked engine block is gluing. Engine blocks are subjected to extreme temperatures and pressures during operation, which makes it crucial for repairs to restore structural integrity and withstand mechanical stress. While gluing may be effective for some low-stress applications or temporary fixes, it cannot provide the necessary strength and durability required for an engine block repair.

In contrast, methods such as pinning, magnafluxing, and welding are commonly employed in the industry to address cracks in engine blocks. Pinning involves inserting steel pins into the crack to reinforce it, while magnafluxing is a non-destructive testing method used to locate surface and near-surface cracks by using a magnetic field and a ferromagnetic powder. Welding can effectively fuse the cracked elements back together, especially when done correctly with the right materials and techniques.

Overall, the choice of repair method is important for ensuring the longevity and reliability of the engine after the damage has occurred, making gluing an unsuitable option for this particular application.