is generated from iron or steel alloys from such sources as:

Source:           Blocks, Gears, Rings, Bearings, Cylinder Walls,
                      Cylinder Heads, Valve Trains, some engine
                      Pistons, Shafts, residual Rust.

 Function:        Because of its strength, iron is the base metal of
                      steel in many parts of the Engine. 
                      Since iron will rust, it is alloyed with other metals
                      (i.e. Cr. Al, Ni) making steel.

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