What Is An Engine Block Heater And Do You Need One?
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For much of the U.S., the concept of an engine block heater is a foreign one. Even areas like the mile-high city (Denver), which faces its fair share of winter cold, are considered mild in comparison to states that border Canada. For example, in Grand Forks, Minnesota, the average temperature is below freezing for as many as 5 months each year. This kind of extreme cold is hard on an engine. Fluids can become thick in low temperatures, which makes starting a car a difficult prospect.
Fortunately, there are various ways to beat back the cold, including some your favorite cold-weather car mods like an engine block heater. The engine heater was originally invented back in 1947 by a North Dakota man named Andrew Freeman. Freeman added an electric powered heating element under the hood to warm vital engine fluids. Today, there are a few varieties of these heaters — some warm the oil, while others warm the coolant.
Whether or not you need an engine block heater comes down to your location and the severity of winters your area experiences. For example, if your local temperatures often dip beneath 10 degrees Fahrenheit, you could benefit from an engine block heater. If, on the other hand, things rarely get that cold, and if they do, it only lasts for a few days, you shouldn't bother with one.
The different types of engine block heaters
There are quite a few options in terms of the engine block heaters available. Some are applied externally, while others are more complex, requiring you to remove parts or tap directly into the coolant system. While not the only method of powering these heaters, most of them feature a plug that utilizes household AC outlets. And in case you're wondering, here's what engine oil looks like during a sub-zero temperature cold start – it's so thick that it won't even drip off the dipstick.
Some of the more basic options, like an engine block warming blanket, can be found for just over $300 and simply rest on top of an engine. Engine dipstick heaters are less expensive at around $50 and feature a heating element that goes down into the block to warm up the oil. Finally, you can find adhesive heating pads or magnetic ones, which can be installed on the oil pan or on the outside of the engine block and start at around $14 (for the adhesive pads) and around $40 (for the magnetic).
A few of the more involved versions of these products, like a frost plug heater, require you to replace stock components with parts equipped with small heating elements. Frost plug heaters warm up the coolant and come in a wide range of prices, depending on your vehicle's make and model. There are also inline coolant heaters, which go inside a coolant hose, warming and circulating the fluid gradually. You can find these starting at around $60, but you must ensure that the product will fit your vehicle properly.
Why idling your modern vehicle isn't typically a viable solution in chilly climates
You've probably heard that warming up your engine is just a matter of starting it and letting it idle for several minutes. However, this practice is largely a holdover from the automotive past, when cold engines with carburetors would fail to atomize fuel, often leading to vehicle stalling issues. However, modern cars are equipped with fuel injectors, which add more fuel to the engine, causing it to run rich while cold in order to solve this problem until the engine warms up. This, unfortunately, isn't the only misleading vehicle recommendation out there, as these are the worst pieces of car advice you've heard, and there are some doozies.
Here's the problem: Idling your modern engine and forcing it to run rich for extended periods can cause unburnt fuel to remove oil from vital places like the cylinder walls. Without the protection of oil, friction between metal parts increases, and so does engine wear. Furthermore, contemporary engines are often completely lubricated in less than a minute. So, idling a modern car to warm it up (in most cases) is unnecessary, as it takes much longer to heat up while idling than simply driving it gently.
That means that, if you simply crank the ignition once you get in the car, by the time you're buckled in and settled, the vehicle should be ready to drive. That said, you still shouldn't floor the gas right out of the gate, as this can put too much stress on the engine. For those in frigid climates, opting for an engine heater is much healthier for your vehicle, as it can warm up the fluids for a few hours before driving, without extensive idling.
