Overheating Engine-Freewheeling Fan . Toyota L Engine Guide

Overheating Engine-Freewheeling Radiator Fan

Have you seen a freewheeling radiator fan?

Radiator fan or cooling fan is a part of the cooling system of an engine. It is attached to the front of the engine facing the radiator to cool it whenever the engine starts and the car is used on a trip or a journey.

The radiator fan blade is not fixed like other fans such as electric fans. It’s neither like the processor fan of a computer that is too loose. The story below tells you more about this for you to understand in case you still don’t, why a radiator fan is designed in such a way that it can turn left and right but not too loose.

It was far from my own belief that this situation has been the long-lurking issue of engine overheating since the engine was overhauled.

Nobody of us noticed that this radiator fan is no longer working efficiently and posed us to wonder for several months.

Until just this week we happened to discover because we were trying to analyze if the water pump is working. As we were contemplating my assistant happens to touch and move the radiator fan, and there it’s freewheeling. Please see the video below.

In normal condition, the radiator fan should not rotate freely. It should hold the fan blades quite stiff but not permanently. It should rotate both clockwise and counter-clockwise but not too loose.

Because this radiator fan is freely turning left and right when the engine runs the radiator fan blades will not rotate to the maximum speed to cool the radiator. The result would be engine overheating even in highways and smooth roads. The more the engine overheats when rev is exerted to climb uphill.

That was the case so we have to restore this failing radiator fan. Please watch how it was disassembled.

So it was disassembled and cleaned and refilled with silicon oil. It is not so complicated it is easy to disassemble and clean.

What tools and materials you need to restore this model are a 10 mm socket wrench, a Philip screwdriver, an impact driver, and a silicon oil-four pieces of the size shown in the picture.

Overheating Engine-Free Wheeling Radiator Fan-10mm socketOverheating Engine-Free Wheeling Radiator Fan-Impact drive

Overheating Engine-Free Wheeling Radiator Fan-Philip Screw Driver

Overheating Engine-Free Wheeling Radiator Fan-Silicon oil

As you see it in the video the fan blades are no longer freewheeling.  The silicon oil holds it but not so firmly and not too loose so that when the engine runs the cooling fan rotates.


Why is the Cooling Fan Not Fixated?

The purpose of that design is to give flexibility to the fan blades so that when something hard is accidentally inserted when the engine is running it will not be forcibly broken.

As the hard object is still there and the engine continues to run the fan blades will stop without being broken and you will have the time to remove that hard object.

No engine breakage, no cooling fan breakage too and the journey continue.

If you are sure your cooling fan cannot be rebuilt go to the alternative ones. Have them here.

Overheating Engine-Freewheeling Radiator Fan-Car on a journey



6 thoughts on “Overheating Engine-Freewheeling Radiator Fan”

  1. Hi this is great. I appreciate the tips on your site. My wife and I are getting a new car soon and we will be looking to buy a decent one to last a while. So proper maintenance of the car will be really important. Thanks for sharing this information with me and other site visitors.

    • Hello, Kenny. I’m sorry for the delayed response. I have overlooked your message. Yes, proper maintenance is the only way to make your car last for a longer time. Bear in mind this freewheeling radiator fan for you might encounter this at least you’ve read and you can be guided.
      I hope you’ll come again and bring your ideas on what information you can avail here.

  2. Dear Accad,

    Thanks for the informative post on the radiator fan.

    The videos you embedded on your post are really helpful. I got new insights from your post.

    To be honest I am not aware anything about radiator fan but after reading your post, now I know about its function, why it is designed and the purpose of that design and its benefits.

    Very helpful post and wishing you great success!


    • I hope you will not use this in any way Paul.  You may have a new model of your own car. However, you can share what you have learned here to other people who have older models of car.

      Thank you for coming by and I hope you will come again next time.  Please share the good news.

  3. HEY Accad

    This is  good information.Here a while back  I had the same problem.when my car overheated.It took me a wile  figuring out how to change the fan.I  got it done . I would have saved time and money.following the steps shown on this site

    Thanks a lot great information for when you want to get a job done right.

    • Good to hear that Freddie. We have done it. Often times we thought a thing is always good but has not really checked on it. In a car, sometimes we need to really feel it through our hands, it is only then that we can see defects in them.

      We can really do it by ourselves when we have the right understanding of the systems or groups and how they function.

      Radiator fan or cooling fan as others say is a little bit covered so it cannot be immediately noticed when you are facing the engine unless you look under the cover and touch it, try to rotate it.


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