They can serve as some protection against dirt, but they cannot protect engines against bangs of ice, stones on the roads, pits and other. More than that, engines in many cars are not protected from the bottom at all.
Nad kaitsevad mootorit mõnevõrra pori ja vee eest, kuid ei suuda seda teha jäätükkide, kivide, aukude ja muu sellise eest. Mõnedel autodel pole mootor aga allpoolt üldse kaitstud.