retmil46 wrote:
With those outside temps, 2 hours just aren't going to do you any good. The sticker on the cord states that's only a 1000 watt heater, the equivalent of 5 or 6 good-sized light bulbs.
I'd try doubling the amount of time, go to 4 hours, and see what that does. I wouldn't be worried about burning out the heater or overheating the engine, most block heaters are designed to be plugged in all night as it is. If you're really concerned, call the service department at the dealer.
By way of example, I've plugged mine in here in NC when the temps were in the 40's for 4 hours. When I started the engine, the coolant temp gauge didn't even budge. But the engine reached full coolant temp in about half the time it would have if I hadn't had it plugged in.
From what I've seen, this block heater isn't designed to raise the engine to full operating temperature. More like it gets it to the point where it's the equivalent of starting it on a warm summer day.
Do we all have a coolant block heater, or an oil block heater? I don't know yet, but my father-in-law has a Ford Powerstroke Excursion and his is an oil block heater that actually heats and circulates the engine oil throughout the block. So his coolant is initially still cool.
If ours is 1000watt that is more in line with an oil heater...