If you're talking about a ratchet-head, then yeah, you can use it as a bowl. I've used those before, though 1/4 is the biggest I've tried. If it tastes like tire, the metal may have a coating that needs to burn off, or there might be some kind of residue on it.

As there's no sure way to know what kind of metal it's made of, I'd be careful. It's probably pot-metal, so it could contain lead and all other kinds of goodies. If you can't find foil (which is safer than some unknown), or a soda can, and you can't make a bottle bong, and can't roll a joint.. Then i guess you probably won't die using it two more times. But seriously, you can't find ANYthing to roll a joint out of?

Good luck, brother.

Addendum: You can even make a pipe out of fruit or veggies, for fuck's sake. Be creative.