How to Check and Top Up Your Coolant (Engine Antifreeze)

Coolant, also known as antifreeze, plays a vital role in your vehicle’s engine health. It helps regulate the engine temperature, preventing it from overheating in summer and freezing in winter. If you’re driving a car, van, or campervan, keeping coolant levels in check is a simple maintenance task that can save you from serious mechanical issues and costly repairs.

Checking your coolant only takes a few minutes, and it’s something you can do yourself with minimal tools or experience.

What is coolant and why is it important?

Coolant circulates through your engine and radiator, absorbing heat and keeping the engine within a safe temperature range. Without enough coolant, the engine can overheat, especially during long drives or hot weather. This can cause damage to vital components and lead to breakdowns. In cold weather, coolant also stops the water in the system from freezing and damaging internal parts.

How to check your coolant level

Before checking, make sure the engine is completely cool. It’s best to wait at least 30 minutes after turning off the engine.

Open the bonnet and locate the coolant reservoir. This is usually a semi-transparent plastic tank that allows you to see the fluid inside. It will have clear markings showing the minimum and maximum levels. Your coolant should be between these two marks. If it’s near or below the minimum, it needs topping up.

While checking the level, take a look at the colour of the coolant. It’s typically pink, green, or orange, depending on the type used. If it looks dirty, rusty, or sludgy, it may be time for a coolant flush and replacement, rather than just a top-up.

How to top up your coolant

Make sure the engine is cool before opening the reservoir cap. Slowly unscrew the cap to release any pressure safely.

Add the correct type of coolant for your vehicle — you can find this information in your owner’s manual or on the coolant cap. Pour it in slowly until the fluid reaches just below the maximum line. It’s important not to overfill, as the coolant expands when it heats up during driving. Once topped up, securely replace the cap.

When to check coolant levels

For regular drivers, checking coolant every three to four weeks is a good habit. If you’re driving a campervan or going on long road trips, it’s wise to check before every journey. You should also check more often during very hot or very cold weather, and any time your engine temperature gauge shows unusual readings.

Coolant maintenance for campervan owners

If you travel frequently in your campervan, particularly in remote areas, staying on top of coolant levels is essential. Overheating in the middle of a trip can quickly become a costly and time-consuming problem. Make coolant checks part of your pre-travel routine to keep your journeys safe and stress-free.

Keep your vehicle running smoothly

Coolant maintenance is one of the easiest ways to protect your engine and avoid unnecessary repairs. It’s quick to check and even quicker to top up — making it a perfect task for your weekly vehicle check.