Do I need to warm up the engine in winter?
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Do I need to warm up the engine in winter?

The topic of the need to warm up the engine in winter is eternal. There are probably more opinions on this than the stars in the sky. The truth is that for people far from developing and improving car engines, this topic will remain open for a long time.

But what does the person who creates and optimizes racing engines at the American company ECR Engines think? His name is Dr. Andy Randolph, and he designs NASCAR cars.

Two factors that a cold motor suffers from

The engineer notes that a cold engine suffers from two factors.

Do I need to warm up the engine in winter?

Factor first

At very low temperatures, the viscosity of the engine oil increases. Lubricant manufacturers are partially addressing this problem. They, roughly speaking, mix components with different viscosity characteristics: one with a low viscosity index and the other with a high one.

In this way, an oil is obtained that does not lose its properties at low or high temperatures. However, this does not mean that the viscosity of the oil is maintained with decreasing temperature.

Do I need to warm up the engine in winter?
Viscosity of different oils at a temperature of -20 degrees

In cold weather, the oil in the lubrication system thickens, and its movement in the oil lines becomes more difficult. This is especially dangerous if the engine has a high mileage. This results in insufficient lubrication of some moving parts until the engine block and the oil itself get hot.

In addition, the oil pump can even go into cavitation mode when it starts sucking in air (this happens when the suction rate of oil from the pump becomes higher than the suction line capacity).

The second factor

The second problem, according to Dr. Randolph, is the aluminum from which most modern engines are made. The thermal expansion coefficient of aluminum is significantly higher than that of cast iron. This means that when heated and cooled, aluminum expands and contracts much more than cast iron.

Do I need to warm up the engine in winter?

The main problem in this case is that the engine block is made of aluminum and the crankshaft is made of steel. It happens that in cold weather, the block compresses much more than the crankshaft, and the shaft bearing sits tighter than necessary.

Roughly speaking, the "compression" of the entire engine and the reduction of clearances leads to increased friction between the moving parts of the unit. The situation is aggravated by a viscous oil that cannot provide adequate lubrication.

Warm-up recommendations

Dr. Randolph definitely advises to warm up the engine a few minutes before driving. But this is just theory. How much does the engine wear out if the average driver starts driving every day in winter, as soon as they start it? This is individual for each engine, as well as for the driving style that the car owner uses.

Do I need to warm up the engine in winter?

What can you say about the opinion of respected experts about the dangers of warming up?

No one will argue that even among professionals there are those who are sure that prolonged heating of the engine can damage it.

In fact, there is no need to stand idle for 10-15 minutes. The oil takes a maximum of 3-5 minutes to reach its operating temperature range (depending on the brand of lubricant). If it is minus 20 degrees outside, you will have to wait about 5 minutes - that's how long the oil should heat up to +20 degrees, which is enough for good engine lubrication.

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