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Engine Heater, Cold Start but oil at Operating Temperature already?

I’m taking a class at my local community college about engines. I have a conceptual question. I’m learning about cooling systems, and surprised that over cooling is actually thing. You don’t want to operate the engine for extended periods of time to cold, you want the engine to reach operating temperature as quick as possible. So you don’t want the engine to be too hot or too cold, but at operating temperature. Is there some sort of add on device that I can hookup to my car, like an oil pan heater, that is battery operated and doesn’t require 115 VAC (I park in a parking lot). That I could remotely turn on before starting the car. This would ensure that the engine oil is at operating temperature before I start the car. Would there be any benefit to getting the oil to operating temperature before starting the car?

It takes a lot of watts for a heater to warm the engine.

So, a 12VDC source isn’t sufficient enough to provide high enough of wattage for that task.

That’s why car engine heaters are 120VAC powered.



So if I could hook up at 120 VAC engine heater, would there be any benefit for this, or is that only for colder climates? Just a heating element that attaches to the oil pan. It would seem to me like starting the engine with the oil already at operating temperature of the engine would be beneficial, even if I don’t live in extremely cold climates. I live in Connecticut, so some winters get into single digits.

Why are you not asking this in class ? You are paying for it so use it .


Good point! I’ve been asking lots of questions, but didn’t have this one until we already went over cooling. I’ve really been enjoying the class though!

If there isn’t a convenient time in class to ask this question, stay after or go in early to ask the teacher.

I believe there would be a tiny reduction in engine wear, but not enough to have any real-life impact.

As already mentioned, the battery capacity you’d need for this would be prohibitively expensive, not to mention that charging it would be a pain.

It would be better to have the engine coolant warm when starting the engine. 95% of the oil is sitting in the bottom of the pan but the coolant is always throughout the engine and in contact with the block and heads.

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Interesting. Is there a coolant pre-heater device that can heat the coolant before you start the car?

It is true an engine would benefit from some kind of preheating. But the benefits are too small in most cases to warrant the expense of accomplishing it.

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They sell engine block/ frost plug heaters.

A frost plug is removed from the engine block, and one of these heaters is installed in its place.

The heating element is immersed in the coolant.


using synthetic oil will help starting at low temps

Yes as Testers post shows . But how many people really need to go to that much trouble ? Also how many are just going to drive off without unplugging the silly thing . What is this going to add to the engine life in miles . Probably not much.

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Yes, as has been posted above you can install a block heater if the engine has accessible freeze plugs. Many modern day cars don’t. There are also heaters that splice into a radiator hose.

Unless you live in a very cold climate you don’t really need any of this.



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Boy, did You get that wrong. Many - if not all - big rigs today have either a gas (benzin) or diesel heater system workíng on 24 volts installed. And an increasing number of cars (12 volts) are sold brand new with the same systems. One of my friends has a little sh??box Seat Mee with a factory installed heater which he turns on 20 min. on the remote before take-off and the cabin is cosy, the engine is at 60 celsius, the windows are clear due to the heater fan being turned on also even when its below 0 Fahrenheit. He has had the car for 3 years and the car still retains its original battery from 2012.


No type of oil pan or block heater is going to get the engine up to operating temp. They are only there to warm the oil or engine enough to be able to start the vehicle in frigid temps. Th quickest way to get the engine up to operating temp is to drive the car. It also means no remote start, no starting it and going back in the house for more coffee and no idling, just be gentle on the gas for a few blocks. Now all of this may be hard on you, but you were asking about what is good for the engine.

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It would appear you didn’t read the OP’s question.


Our last 2 cars came with block heaters in WI. The current cars did not. I used them when temp was 15 degrees or less. I was told once they stop heating when the coolant gets to 35 degrees. It sure makes those cold weather starts easier. In ND there were outlets by parking spots. Usually the body goes before the engines, Many cars without block heaters get plenty of miles on them, so I don’t know that it makes that much difference on engine wear. Hanging the cord over the driver side mirror was good enough for us.

Mister Tester. It should be quite obvious that I responded to YOUR statement, NOT the question from OP. And I still say that YOUR statement is wrong. It is not my problem that You are in a wrong place of this planet where it may not be possible to obtain features that is common in other parts of this planet.
What I AM stating is that -
OP - IT IS possible to buy accesorries to your car, which will keep your life easier without robbing a bank. Eberspacher and Webasto are just a few names to mention.
Over and out for ever.