what purpose does the engine block heater serve
In colder climates it a must have just to get the engines started, it warms not only the block but the oil and coolant as well, works the same on both gas and Diesel engines. Some diesels even have a fuel heater to keep the fuel from gelling in really cold temperatures. Hope this answered your question.
Yep, that is what it does, I live in the U.P. where it is cold in the winter time.
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