Replace Engine Coolant


Fill the engine radiator through the coolant reservoir, a plastic tank near the radiator.

The Fix-It Club offers hundreds of free Fix-It Guides on how to repair household and automotive things. One of the most important car maintenance jobs is making sure that the engine has enough coolant to keep the engine running cool for many miles. Coolant, like everything else on a car, wears out with use and time. So it makes sense to replace coolant periodically. Many car manufacturers recommend coolant be replaced with new stuff about every two years or 30,000 miles.

Replacing coolant is relatively easy. Getting rid of the old stuff isn’t. For most cars, removing coolant means putting an appropriate container underneath the radiator and opening a small valve that allows the coolant to flow out. Once done, close the valve and refill the radiator and reservoir with coolant. (Refer to the car’s owner’s manual for capacity and mixture information.)

When you replace engine coolant, also replace the radiator cap.

When you replace engine coolant, also replace the radiator cap.

Also, replace the radiator cap when you change coolant. It costs just a few dollars. Its job is to keep coolant adequately pressurized, a relatively important task.

Fix-It Tip

Check your car’s shop or owner’s manual for specific instructions on replacing coolant. Some models require that air be purged from the cooling system because the engine is higher than the radiator.

Because antifreeze can be poisonous to animals and children, get rid of it properly. The best method is to pour it back into empty antifreeze containers and take it to a hazardous waste recycling center. Never pour it down a household drain!