Squeeze the radiator hose to see if the coolant is frozen. If it is, the water pump is likely frozen too and the serpentine belt burned off. That would explain the smoke and the lack of heat.
The proper coolant mixture is 50 percent water and 50 percent antifreeze. That will get you to a freeze point of close to -40 degrees F. Obviously a lower percentage of antifreeze will result in a higher freeze point, but so will a higher percentage of antifreeze. You can get close to -50 degrees F. With a little higher concentration of antifreeze, but then the freeze point goes up from there. Simple freeze-point testers just measure the weight of the coolant compared to the weight of water, and those lose their accuracy beyond -40 degrees. The point is, more antifreeze is not better. A 50 / 50 mix is the best you can do.
Now that the damage has been done to the belt, (I'm assuming), letting the engine sit like that is eventually going to crack the engine block. This assumes the coolant really is frozen. If you can pull the car into a heated garage, that will save the engine. If not, I would start it and run it for five or ten minutes a couple of times per hour to keep it from freezing again. It is likely the heater core will crack because the heat isn't going to migrate up to it and thaw it out, but when the coolant freezes inside the engine, it doesn't usually crack the block right away. Running the engine intermittently will keep the coolant from freezing in the block. Covering the front of the car with a blanket will help too.
If the engine has a block heater installed, plug that in instead of running the engine, but that also will not save the heater core or the radiator. If you are lucky and there is just a little too much percentage of water in the system, the coolant will not freeze solid right away. It will be more like slush. That is much less likely to cause broken parts but it will cause poor circulation, including to the heater core. You'll know for sure once it warms up and you see if there is coolant leaking out. If the coolant level goes down and the oil level goes way up, the block is cracked and it's all over for the engine. If you see coolant on the ground under the engine, it could be as simple as the ice pushed a core plug out. That is a major coolant leak that is relatively inexpensive to repair, but that often saves the rest of the engine from cracking.
Monday, January 6th, 2014 AT 4:10 PM