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AA Rescue Guide to checking your coolant

Advice from AA Patrol, Trevor Freeman

Here AA Patrol, Trevor Freeman, who has been rescuing broken down Irish motorists for more than 7 years, shares his step by step guide on how to check and refill your coolant tank if required to avoid a breakdown.

Before you get started

There are two important things to remember before you get started:

All modern cooling systems are sealed and as a result they shouldn’t ever really need topping up between car services provided everything in your vehicle’s engine is functioning correctly.

It’s a pressurised system and as such should only be checked or topped up when the car’s engine is cold.

Identifying your vehicle’s cooling system:

Your car’s cooling system will usually have a coloured cap, however the best practice if you don’t know where it sits within your vehicle’s engine is to check the car manufacturer’s manual.

Checking your vehicle’s coolant level

In most cars, the coolant tank will have a maximum and a minimum mark on the exterior. More importantly your vehicle’s coolant tank is made of a transparent material so that you don’t have to remove the cap to check it. The coolant should be between the maximum and minimum marks.

How often should I check my car’s coolant level?

To avoid a potential break down, we advise motorists to check their car’s coolant level weekly. This weekly check, which should form part of your regular vehicle maintenance activities, will allow you to spot a coolant leak and pre-empt a break down. An undetected coolant leak will cause your car to overheat when you drive it.

For more information on what to do if your car breaks down click here

Topping up your vehicle’s coolant tank

If you notice that your vehicle’s coolant level has dropped it’s important to take it to a good car mechanic. We recommend an AA or SIMI appointed garage for this. To find an AA appointed garage in your area click here.

In the meantime, to prevent your car breaking down you will need to top up the coolant level. To do this, first and foremost you need to make sure that you’re using the correct coolant.  Secondly you should make sure that the car’s engine is cold.

Most antifreeze will need to be added to water before they are added to your car’s coolant system. The general rule of thumb tends to be 50:50 but you should check your vehicle’s instruction manual to make sure you’ve got the right mix. 

When you’re sure your car’s engine is cold you then need to open the coolant tank’s cap. There might be some residual pressure in there so you might hear a little hiss. You’d then take the container with the suitable anti-freeze mix in it, using a funnel if needed and top your vehicle’s coolant level up until it reaches the maximum mark making sure not to overfill it. Going past this mark means you’ve taken away some of the room the coolant needs to expand as it’s an expansion tank.

AA Members enjoy access to Ireland’s largest and best equipped Breakdown service plus fabulous deals such as cheaper AA Car and Home Insurance, a discount on AA Car Servicing and savings on a wide range of accommodation, tourist attractions, restaurants and retail outlets. To become an AA Member click here or call +353 (0)1 617 9977