Installing a Radiator Overflow Tank

  • 1-3 hours
  • Beginner
  • 25-50
What You'll Need
Socket set
Overflow tank

A radiator overflow tank is used to help with the coolant fluid that expands and contracts in automobiles. If you look near the radiator fill cap, you should see a clear plastic reservoir tank. It has a small hose attached to the cooling system of the vehicle. Listed below are the steps that it will take to complete the installation. If you have a mechanical background, you should be able to complete this in just a matter of 20 minutes or so.

Step 1 - Preparations

Now that you have the tools in hand it is time to remove the old radiator overflow tank. Release the hose clamp and pull firmly to unplug the reservoir from the tank. Then turn the mounting bolts counterclockwise to loosen them. If you have an elongated tank, look for bolts that may be hidden by engine components.

Step 2 - Removing the Old Reservoir

Pull the old radiator overflow tank free to remove it. Sometimes you will find the computer to the car on top of the reservoir. So carefully set aside the computer to remove the reservoir. This is true for General Motor products.

Step 3 - Putting in the New Tank

You can now put the new tank in and position it so that you can secure the bolts, but do not over tighten them. If the bolts are over tightened they can split the tank. The bolts tighten clockwise.

Step 4 - Connecting the Tank

Connect the new radiator overflow tank’s lower hose by connecting it to the nipple and tighten the hose clamp. You may have to pinch them or they may be the screw type. The OEM models have the pinch type clamps.

Step 5 - Replacing the Computer

Once the new tank is in place, gently replace the computer and any other engine components that were removed. The mounting bolts will be turned clockwise and then you can plug the adapter back in securely.

Step 6 - Finishing Touches

Be sure to check the proper levels of fluid in the tank before you go to refill it. The tank is equipped with an open vent cap. This releases pressure as it opens to allow the coolant to expand. As the coolant expands, the fluid is forced into the tank by the lower hose, thus forcing air to escape into the tank. This will allow the cooling system to expunge the air which will cause lowering the cooling ability and regulate the coolant pressure.

As you can see, the installation of the reservoir tank is very simple to do. Anyone without a mechanical background can install one of these in a very short time. All you need is the proper tools and the new equipment. If you should ever be unsure of what to do, you can look the instructions up online or have a friend give you hand. It is a great way to save some money by doing the repairs yourself. You can even teach someone else how to install a radiator overflow tank and help them save money too.