Summer Is Coming. Time To Be Cool

This winter we are currently experiencing may not be the most extreme British motorists have ever had, but it’s been bad enough. Slipshod repairs to roads means your car’s suspension system has been working overtime to keep you on the straight and narrow. The vehicle’s lights, washers and wipers have been working overtime and all through the process of driving the coolant in your radiator has been flowing through to draw heat from the hard-working engine.

All Year Round

It does this by circulating coolant liquid (usually water mixed with an antifreeze solution) through special cooling passages in the engine. The Coolant helps to regulate the temperature of the motor, ensuring it gets neither too hot nor too cold. Maintaining optimum levels of fresh coolant also helps prevent internal rust and corrosion, since coolant contains corrosion inhibitors.

Without coolant, the engine will overheat and eventually seize-up: Without antifreeze, in winter water alone or a weak mixture could freeze with likely the same outcome. Antifreeze though is not just for winter; it should be used throughout the year. Ideally, owners should check the car’s coolant reservoir once before the winter and once before the summer to ensure it is at optimal capacity (see the handbook). Using antifreeze in the engine in the Summer raises the boiling point of the cooling system’s water and ensures the engine does not overheat, on, say, a very hot day in a traffic jam and most of us have experienced that.

Cooling System Maintenance

Most modern cars have sealed systems that are essentially maintenance free but car makers do recommend changing the coolant and flushing out the system every thirty to fifty thousand miles. Note: This figure is not set in stone. How the car is used will make a difference, for example, a lot of stop/start driving or long distances in a very hot climate (not very likely in the UK, granted). Once, before the days of sealed systems, changing the coolant or fitting a new thermostat were simple tasks that most reasonably knowledgeable car owners could handle with ease.

These days though, the sight of vehicles stranded at the roadside with steam pouring out from the engine bay are largely long gone thanks to sealed systems; we just let the car get on with it. However just because the cooling looks after itself, that doesn’t mean it should be neglected. For example, hoses can wear out and other malfunctions can occur which is why we should all ensure our cars are regularly maintained by a professional car servicing garage. Yes, a skilled amateur car mechanic could change the coolant on a modern car but for most users, these days it is a more specialised task. Cars have become more complicated.

Distilled Water

Ideally,  the coolant in your car is comprised of distilled water and antifreeze. The ratio of these two fluids needs to be correct, or it won’t work as required. It is important to note that the ratio will vary between different car models. That sounds more complicated than it is as most mixing ratios are between 60:40 and 50:50.

Although these days tap water is not exactly a free resource, it would still be tempting to use it when mixing coolant: don’t. Tap water contains organic contaminants and minerals which can build up in your car's coolant system and lead to corrosion. As long as it’s the right ratio solution it is fine to use proprietary ready-mix brands from your local garage or motor factor.

Should You Do It Yourself?

As mentioned, modern cars are complex and the manner of draining the system is as easy as it used to be. It’s necessary to locate the drain pipe or tap (on a cold engine) and catch the water when it comes out for proper disposal (it’s toxic and dangerous to humans and animals). The system then has to be flushed to remove lingering contaminants before refilling with the correct mix. Access to the underside of the engine bay is needed and of course tools will be required.

It’s far better to let your garage do it. They will have ramps or inspection pits: They know how your car works and what its requirements are and they have the correct tools. The system requires bleeding thereafter to remove any trapped air. The system then needs to be checked for leaks from the radiator, the hoses (including the usually inaccessible heater hoses). Hose clamps need to be checked and replaced if necessary and so on, so you see it’s not quite as simple as it appears to be.

Let Your Garage Do it

At worst, this is probably a once in an ownership lifetime job. When you sell a car on it becomes another person’s issue. Your local car servicing garage has the knowledge and expertise to attend to this,  so when your car reaches a certain mileage, why not add a coolant change on to the regular service; the car’s going to be in the workshop anyway. This is how to stay cool this Summer.