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Five fluids you should check regularly

It might be a machine, but it’s not a miracle. Here’s what you should check and top up on a regular basis.

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Just as humans need a steady supply of water, cars also need fluids to continue running well. Without the correct levels of solutions in the right place at the right time a car will, sooner or later, give you trouble.

Leaving fuel to one side – because without it, your car is definitely going nowhere – there is an array of other vital fluids that your vehicle’s engine requires for it to continue working in a safe and reliable manner. Leave any of these neglected and you could be doing some lasting damage to your engine.

So don’t disregard dashboard warning lights or other tell-tale signs when it comes to your fluid level checks and top-ups, which should be done regularly. Here are the main ones to look for and how to replenish them.

It’s crucial that you use the correct fluids for your vehicle, as the wrong fluids can cause expensive damage. If you don’t feel confident doing any of these yourself, get an expert from your local garage or workshop to do it for you. The main thing is – don’t ignore it.

Engine oil

An engine’s lifeblood, the importance of motor oil cannot be overstated. It lubricates moving parts so that they’re not worn by friction and adds an element of cooling while helping to reduce the build-up of sludge from older oil. 

To check the level, find the dipstick in your engine bay – it’s usually coloured brightly. Pull it out, wipe it clean and then re-insert. Remove it again and look at the level of oil showing on the stick. There will be a high or ‘full’ marking and a low or ‘minimum’ one. You want to see oil between these markings, towards the higher end.

To replenish, find the oil cap –it should be obviously marked in a bright colour or with an oil can image on it. Fill with fresh oil slowly and check the dipstick again for the new level.

Engine coolant

Another vitally important fluid – it stops the engine overheating. It’s basically water but with an equal measure of anti-freeze solution in there to stop things icing up over the winter months.

In an emergency, water alone can be added to the coolant system but this should be topped up with anti-freeze as soon as possible. The coolant reservoir is plastic and should have markings on the outside showing the maximum and minimum levels. Check this when the engine is cold.

The filler cap will have the word ‘coolant’ on it and perhaps a thermometer symbol. Pressure can build up in the system so when you unscrew the cap, do so slowly and with a rag held over the top to catch any splashes. 

Brake fluid

Brake fluid is part of a hydraulic system and enhances the pressure you exert on the brake pedal. Without the correct level of fluid your brakes will be seriously affected and become much less efficient.

The brake fluid master cylinder is under the bonnet and has a reservoir attached to it which has the ‘full’ marking on it. The fluid level should be topped up to this level. Only use the recommended brake fluid for your particular car.

Power steering fluid

This is certainly one to keep an eye on, although power steering fluid doesn’t need tending to very often, unless there’s a serious problem with your system.

It’s designed to last about 80,000 miles, though some modern cars will go on longer than this. Checking it can be done in a similar way to the brake fluid – the reservoir will be made of plastic and the level marking should be on its side for easy inspection. If it does need replenishing, carefully remove the cap and pour some new fluid in.

Windscreen washer fluid

It’s probably the easiest of them all to check and replenish. The reservoir will have a windscreen symbol on it – the cap can be opened and the contents inspected at any time as the fluid is not pressurised and does not get hot.

There are many additives available to buy that you simply add to water before filling up. These help to clean the front and rear screens better than if you used water alone.

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Tom Johnston
Tom Johnstonhttp://johnstonmedia.com/
Tom Johnston was the first-ever reporter on national motoring magazine Auto Express. He went on to become that magazine’s News Editor and Assistant Editor, and has also been Motoring Correspondent for the Daily Star and contributor to the Daily and Sunday Express. Today, as a freelance writer, content creator and copy editor, Tom works with exciting and interesting websites and magazines on varied projects.