My girlfriends 87 normally runs great and stays at a very low normal temp. However this morning she drove it and as soon as it got up to operating temp it starts smoking from under the hood and temp rises drastically! It's a 22r carb'ed. I checked oil and it was low (about a quart) so I filled back up, then I checked antifreeze and it was low but not much, looked like most was in the overflow bottle.... Also when I try and shut it off it keeps running with the key off?? I need help! Thanks!

 

Rad cap or thermostat

 

Ended up being the rad cap and the fan belt ended up breaking shortly after! Went ahead and replaced thermostat and gasket also just to be safe! Runs great now!! Thanks!