Quoted By:
"Magcargo’s body is over 18,000 degrees Fahrenheit (significantly greater than that of the surface of the Sun, about 10,000 degrees Fahrenheit), which should be hot enough to carbonize flesh. However, it has made contact with Pokémon many times in the anime and none of them felt any burning from its body. This trait is shared with Ponyta, Rapidash, and its own pre-evolution, Slugma.
Despite the fact that water is vaporized on contact with Magcargo, it is doubly weak to Water-type attacks."