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Radiator Overflow Tank

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A Guide to Installing the Radiator Overflow Tank Correctly

Basically, the radiator overflow tank's job is to guide the coolant fluid, which contracts and expands in the car. The tank is a transparent white plastic container that's found just near the radiator fill cap. If this gets busted, you'll have to get this replaced with a new one right away to avoid any leaks or problems that could possibly harm the coolant system. Installing this can be simple if you keep these steps in mind.

Required skill level: Intermediate

List of tools:

  • Pliers

  • Screwdrivers

  • Socket wrench

  • Replacement radiator overflow tank
  • Getting ready for the task

    Before doing the job, you'll have to take out the old radiator overflow tank from the car. This will entail you to let go of the hose clamp and to pull it really hard to unplug the reservoir. Once you find the mounting bolts, loosen them up by turning them clockwise. Take note that if you have an elongated tank, you'll have to locate the other bolts that are hidden. After, you can take out the old tank; if you find a computer, then you'll have to set this aside.

    Installing the new tank

    Once the old tank is out, you can safely install the new radiator overflow tank. Put it in position so that you can place the bolts. Be careful not to tighten them too much because this can cause the tank to split. To connect the new tank, attach it to the nipple and carefully tighten up the hose clamp. You'll have to either pinch it or screw it, depending on the kind that you have.

    Replacing the computer

    If you've securely installed the radiator overflow tank, you'll have to get the computer back as well. Be sure that you turn the mounting bolts clockwise and plug the adapter right back on.

    Capping it off

    For the finishing touches of the installation process, fill the tank with proper level and mixture of coolant. Take note that the tank comes with an open vent cap, which releases pressure while it opens for expansion of the coolant. As this happens, the fluid goes back to the tank and forces the air to exit. This is a sign that the radiator overflow tank is working correctly.

    Radiator Overflow Tank Articles

    • OES Genuine vs. Dorman: Which Radiator Overflow Tank Will It Be?

      Looking for a top-quality radiator overflow tank is quite tricky, especially when there are a lot of brands to choose from. You run around stores or browse through different online shops to get your hands on the right one. However, there are two brands that many car owners have attested to, and those are OES Genuine and Dorman. But, you can't have two of them installed in your car at the same time, can you? So, which radiator overflow tank will it be?

      Product fit

      Even when the choices are narrowed down, some people would still appreciate it if there are different products available under a specific brand. Of course, this will give you a whole lot of options and a greater chance of getting one that's compatible with your cooling system. Fortunately, both OES Genuine and Dorman offer radiator overflow tanks that fit a variety of car makes and models. So in terms of product fit, these two brands are winners.

      WINNER: OES Genuine and Dorman

      Price range

      Price definitely matters to most buyers because the more affordable a product is, the more sellable it would be. However, that's not the case most of the time because there are some consumers who believe that the more expensive the product, the more high quality it is. In reality, that's not true all the time. With Dorman, you can get tanks that are worth around $30 to $80, whereas with OES Genuine, you can get them for around $30 to $270.

      WINNER: Dorman


      You'd surely want to get your hands on a new radiator overflow tank that's top quality to avoid frequent changes. Dorman and OES Genuine replacement tanks are made from plastic and come with a cap. You can even install each one easily because it's a direct fit.

      WINNER: Dorman and OES Genuine


      Warranty matters in every product that you buy because this gives you the opportunity to return it should you discover any defects. Dorman comes with a lifetime limited warranty, whereas OES Genuine comes with a 12-month warranty.

      WINNER: Dorman

      The verdict

      These two brands have different qualities. Dorman may be better at some categories, but OES Genuine could also outdo the other. But, you can only choose one. With the comparisons done, there's no lying that Dorman is the better choice.