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TOP UP ENGINE COOLANT

Learn when and how and when to top up your coolant with Castrol. Understand the importance of coolant for optimal performance, it’s essential to car maintenance.

How to top up coolant

Modern engines generate huge amounts of energy and that energy heats engine parts to very high temperatures. That heat needs to be dissipated and the engine cooled. That’s why it’s important to keep an eye on your levels of coolant and know how to top up engine coolant or how to change it.

 

To replace your coolant, you need to follow a series of steps:

 

1. Make sure that your engine is cool and that you park your car on a level surface.

2. Open the bonnet and find the coolant reservoir. It’s a large plastic container with a coloured liquid inside.

3. Undo the hose outlet at the bottom of the reservoir and drain the antifreeze into a bucket.

4. Dispose of the drained liquid in an environmentally safe way.

5. Once the reservoir is empty, fasten the hose back on and re-fill the container up to the “Max” line with a mixture of engine coolant, anti-freeze and distilled water according to the ratio recommended in your manufacturer’s handbook.

6. Turn on the engine and let it run for a few minutes before you put the cap back on to the reservoir as you want to force any air bubbles out of the system before sealing it.

7. Then locate the bleed screw on the radiator to continue the process of forcing out any remaining air. Open the screw and undo it until a small but constant stream of water starts to flow. As soon as this happens, you can close the screw.

8. Replace any lost coolant and top up the radiator coolant to the ‘Max’ line and replace the cap.

 

Car overheating signals

 

If you become aware of any of the following symptoms, it’s a sure fire sign that your engine is overheating. You should take immediate action. 


1. If your temperature gauge moves into the red zone and the red light activates.

2. If you see steam coming out of the bonnet. This means that the coolant in your car’s radiator has reached boiling point and will need to be replaced. See the section on how to replace engine coolant.

3. If you smell burning. Once an engine begins to overheat, there are many materials that will start to burn. 

4. If your engine starts to make an uncomfortable ticking sound. This may indicate that your engine oil has become too thin and is failing to protect your engine adequately.

5. If you notice a pool of coolant on the ground beneath your car. This is likely to be a sign that your engine has overheated or that you have a leak in your cooling system.

 

What does engine coolant do?


Engines are designed to run within a given temperature and engine coolant, also known as antifreeze, protects engines from overheating. 
As well as protecting against overheating, engine coolant also protects your car’s moving parts against extremely low temperatures through the inclusion of corrosion inhibitors and anti-freeze agents.

 

When should I top up engine coolant?


There’s no hard and fast rule here and some motor manufacturers don’t list a change of coolant in their maintenance schedules. Others will say that it needs to be changed any few years. The important thing is to watch out for any of the signs of potential malfunction listed above.

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