Antifreeze and Coolant

Engine coolant is essential to ensure your vehicle’s engine runs correctly and safely, therefore it’s imperative to understand what it is and how it is used. Here we explain the importance, use and properties of coolant and antifreeze, which are commonly sold blended in the correct proportions as a pre-mixed product, either in concentrated or ready to use forms.

What is coolant?

Coolant is a mix of water and chemicals, for example ethylene or propylene glycol, usually in a 50/50 ratio which is circulated around the vehicle’s engine as it runs. It takes heat away from the engine, brings it to the moving vehicle’s radiator for cooling by airflow, and thereby prevents overheating.

What is antifreeze?

While the terms antifreeze and coolant may commonly be used interchangeably, likely since, as mentioned above, the products are typically supplied pre-mixed, antifreeze has a specific purpose. Antifreeze prevents coolant from freezing in cold weather by lowering its freezing point and helps prevent overheating by increasing the coolant’s boiling point. Other benefits can include protection against corrosion in components including radiator, pump and hoses.

Is antifreeze the same as coolant?

No, antifreeze should be considered as an essential component of coolant that is present to prevent the coolant freezing.

Motoring products retailers such as Halfords tend to categorise these products as simply “antifreeze” on their website but label the products as “antifreeze and coolant” which makes some degree of confusion understandable.

Checking coolant level

The first step is to consult your vehicle’s handbook and follow the instructions therein on how to locate the coolant reservoir and filler cap.

When checking the coolant level, the engine should be cool. The coolant level should be midway between the marked min and max levels. If it is low, it needs to be topped up, otherwise overheating and potential damage can occur.

Can I top up coolant and antifreeze myself?

Yes, you can top up coolant yourself, but it is essential to use the correct variant for your vehicle. Incorrect fluid may damage your vehicle’s engine. Consult your vehicle’s handbook for the specific product to use, or if in doubt, contact a reliable service centre such as Dowleys.

Having located the filler cap, care should be taken when opening, ensuring the vehicle’s engine is cool as steam may escape under pressure, and carefully top up with the correct product to a level between the min and max marks. Do not overfill.

Which coolant should I use?

Coolants come in variants indicated by coloured dyes, each suited to a different group of vehicles, broadly based on age. You should consult your vehicle handbook for the correct product to use and again, we recommend you contact us if you are uncertain. We can carry out a seasonal vehicle check to ensure that your vehicle is in top condition as well as MOTs and full servicing too.

You may see suggestions online of emergency solutions, such as topping up with water, for low coolant levels but we do not recommend any of these options. Acquire the correct product or seek professional assistance as soon as possible.

Book servicing online, contact us for more information or call 01993 842345 for further assistance.