I just moved to South Dakota and the temperature is supposed to be in the teens overnight. I haven't had a chance to install a block heater, does anyone know if i can protect my block from the cold by leaving the radiator cap off tonight until I have a chance to get to town and get a block heater, anti freeze tester and all of the goodies I know I can count on?

 

Unless you have just straight water (which isn't a good idea no matter what climate you live in) in your cooling system "temps in the teens" should not be a problem. Even if you have straight water, for one night, just put a 100watt bulb on an extension cord and put it under the hood next to the block. Close the hood and leave the light on all night. If your coolant (antifreeze) is old, over the next couple of days you should flush out the cooling system and replace with fresh fluid. Make sure the thermostat is working, and make sure your hoses are in good condition. Ask some one who has lived there what the minimum temps usually are in the winter. 50/50 mix will protect from freezing down to about -34 degrees F. That should be good for most winters there but it CAN get colder depending on your location.

Don't know where you moved from but now that you live in S.D. you need to readjust your thinking on what cold means. Temps in the teens is nice weather there! Good luck.

 

I don't even plug my block heater in until around an hour before I drive to work in the morning, and even then only if it gets below zero, or maybe into single digits. If you're somewhere (like it can be here) where you may have days in a row where the temps don't get above the negative teens and the lows are in the negative 30's, then a block heater will help keep your engine from freezing. Otherwise, in more mild temps, I really think their only purpose is to avoid cold starts on your engine. In that case, you don't need them plugged in until an hour or so before you plan to start the truck. You're just wasting electricity and money if you're plugging in overnight in teens or single digits.