Refill coolant to keep your engine running at the right temperature

Keeping your engine running at the correct temperature helps to prevent damage caused by overheating, and your coolant is an essential part of your cooling system.

You need to periodically check and refill coolant in your car to make sure it stays at the correct level in your radiator. Before you get started, make sure you’re familiar with radiator safety.

Watch the video or keep reading for step by step advice on changing coolant.

What you’ll need

Make sure you have everything you need on-hand before you get started. To refill your coolant, you’ll need:

  • Coolant
  • Distilled water (if coolant is not pre-mixed)
  • Rags
  • A funnel (optional)

Using a 50/50 mix of water and coolant is usually recommended. Check your owner’s manual to make sure you have the right type of coolant. Using a funnel isn’t essential, but it can help you avoid spillage.

How to refill your coolant

Refilling your coolant is a fairly simple car maintenance task you can do yourself, as long as you follow the right steps. Before you start, always make sure your engine is switched off and cool.

Follow these steps to refill your car’s coolant:

1. Check the coolant level

Your coolant reservoir should be labelled, and they are usually translucent plastic. The outside of the reservoir should be marked with minimum and maximum lines for the coolant, and you can check here if you need to refill the coolant.

Refer to your owners manual if you are unsure about locating your coolant reservoir.

2. Mix the coolant and water

If the coolant is not already pre-mixed, use an empty container to mix equal parts coolant and distilled water to create the 50/50 coolant and water mix that’s usually recommended.

Longer life coolants are typically higher quality. Always use high-quality coolants for the best result for your engine.

3. Top off the radiator

If there is a cap on the radiator in your car and you can’t see the coolant level, top it off until you can see coolant at the bottom of the filler neck. There may also be a line indicating the maximum fill level.

4. Top off the coolant reservoir

If the coolant level is low in the reservoir, you can refill it to the max fill line but do not overfill it. The coolant mixture expands when it heats up and needs the extra room.

Keeping your coolant at the correct level is one of the ways to keep your radiator good working order.

What type of coolant do you need?

There are two major types of coolant: Type A and Type B. Type A contains anti-freeze and corrosion inhibitor, and Type B only contains corrosion inhibitor.

Mixing different coolant types can reduce the effectiveness of the corrosion inhibitor and damage your engine. If you are not sure which coolant type is already in your radiator, speak to an expert at Natrad for advice.

Do you have more questions about coolant? Read our FAQs here.

Things to remember

Refilling your coolant is a normal part of car maintenance. But if you find you have to top off your coolant frequently, this could indicate your car is leaking coolant. If this is the case, you need have a specialist at Natrad inspect your cooling system.

Along with refilling your coolant, you need to periodically flush and clean the system, and change the coolant entirely. This is more complicated and is usually best to have a Natrad radiator specialist do this for you.

For more information about radiator safety, repairs, or replacements, get in touch with us.