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How to Test Condition of Antifreeze - Freezing & Boiling Points

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  1. step : Testing the Coolant Freezing Temperature (2:17)
    • Remove the cap from the coolant overflow bottle
    • Extract coolant from the bottle with the Anti-freeze hydrometer
    • Check the coolant level on the Anti-freeze hydrometer

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Hi, everyone. I'm Don from In this series of videos we're going to be focusing on vehicle diagnostics and maintenance tips. We hope that you find it helpful and when you need parts for your car or truck, think of Thanks.

In this video, we're going to show you how to check the freezing point of your antifreeze in the car. You're probably wondering why it's important to do it. Well, if you had just acquired your car and you have no service history, or you just haven't had the maintenance done recently, you want to make sure that coolant has a low freezing point, so you don't get stuck in the wintertime with a cracked radiator or other engine damage.

Here we have the tool. It's an antifreeze hydrometer. When you draw liquid in, the bulb up top here, through the tube, the arrow will then point to the freezing point of the coolant.

Now we understand the tool and how to use it, and we've got a little test laid out here. We've got all water, coolant mixed with 50 percent water 50 percent coolant, and then we've got coolant and water, but we don't know what the ratio is. If you're looking into your overflow tank or into your radiator, and you see greenish fluid and you say to yourself, oh, it's got to be fine, there's enough coolant in there, yeah, the level might be right, but the ratio might be off, so looks can be deceiving.

We've got our clean hydrometer going into fresh water, and you can see with the arrow, it's pointed exactly where it should be at 32 degrees. That's the freezing point of water. Get that out. Move over to the mixed coolant and water. Give it a couple taps. You'll see that this is very well protected coolant. Now we're going to go over to the coolant and water, and we don't know what the ratio is, so we're about to find out. As you can see, there's not much coolant, so this could definitely cause a problem in your radiator or in your engine block, so that's why it's important to check what your freezing point is.

Now we're going to test our coolant in our car. We're going to go through the overflow tank here, extract some coolant, and as you can see here our coolant's in really good shape.

We hope this video helps you out. Brought to you by, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.

Tools needed for replacement:

    Diagnostic Tools

  • Anti-Freeze Hydrometer

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