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How to service a car safely

How to service a car safely

Servicing your car or fixing a problem yourself rather than using a garage is a rewarding experience, not to mention a money-saving one. However, a car is a complex piece of equipment and a heavy one, too. So if you’re going to work on it, take nothing for granted and do all you can to stay safe. A good way to do that is by thinking about how a professional mechanic would work on your car.

The professionals are attentive, vigilant and focused on the job. They understand the task from beginning to end, and use the right tools. They remain calm and unflustered, allowing them to think through any challenges and resolve them rationally. Finally, they have a highly developed instinct for safe working.

Here we run through the techniques you need to know to service your car safely, just like a pro.

Do your homework

Study your Haynes Owners Workshop Manual beforehand, away from the workshop. Make sure you leave nothing to chance and understand exactly what the job involves.

Make time

This is where you have an advantage over a professional mechanic who is often working against the clock. Set aside more time than you think you will need to do the job.

Spare parts

If you need any parts, make sure you get them beforehand, rather than having to take a break in the middle of the job. Having to stop and make a parts run interrupts your concentration and causes you stress, especially if the parts aren’t all readily available.

Prepare your working space­

De-clutter the area and have the tools you think you need laid out and ready, just like an operating theater. That includes having waste fluid containers at the ready, as well as all replacement parts.

Dress for the job

Working on your car is a messy and potentially dangerous business, so dress for it. Remove or secure any loose clothing that might get entangled in moving parts such as the belts or fan. The floor and get slippery, and parts and tools can be heavy, so wear sturdy shoes or boots, with oil resistant soles.

Tie back long hair

This is obvious, really, but long hair caught in a spinning drive belt could have very serious consequences.

Keep small children away

A workshop is no place for young children who can be a distraction to you or a danger to themselves. Coolant can look like a tasty drink to a toddler but will cause them serious harm if they drink it.

Let there be light 

Make sure you have plenty of light, especially if you’re working in the shorter winter months.

Keep calm and carry on 

Face every challenge positively, and think rationally. A stressed and anxious mind will simply make more mistakes and exaggerate the significance of others. If it’s all getting too much, take a break and relax, before restarting once you’re fresh again.

Don’t smoke!

Not only is smoking damaging to your health but there are way too many flammable liquids in a car to be playing with lit cigarettes.

How to use ramps, jacks and axle stands safely

Make sure the car is on level ground. Apply the car’s parking brake, put it in gear and then place wheel chocks at the opposite end of the vehicle from where you intend to work.

Now use a sturdy jack that is rated to take the weight of your car, making sure it’s supporting the vehicle at the strongest place as shown in the car’s owners manual, or your Haynes book. Don’t use your car’s spare tire jack. It is made only for emergency use, not regular service and is not up to the task of repeated use..

Having raised the car, you can now position your two jack stands under the correct jacking points as indicated in the manual.  Having done so, lower the car gently onto them. Leaving the jack in contract with the car can be an extra precaution.

Alternatively, you can use ramps of the correct specification to support the car. Since they support a wider area, some mechanics prefer to use these over jack stands. Of course, you can't use ramps if you plan on removing the wheels.

How to undo a radiator cap safely

If you car has a clear coolant expansion reservoir it will enable you to check the coolant level, with little reason to undo the radiator cap. Reasons for doing so might be to check that the cap itself is working, to flush out the system, or to check for oil and water deposits on the neck of the filler indicating possible head gasket failure.

If you must undo it, make sure the engine is cold, and allow at least an hour to elapse after you switch it off. A radiator operates under pressure and if you undo the cap when the coolant is hot, it will spray steam and hot water out of it, most likely scalding you.

As an extra precaution, make sure that when the cap is loose it is angled away from you to direct any residual pressure in the opposite direction. Covering the cap with a rag while opening is a good idea as well,

Safety tip: Never undo the radiator cap of a hot engine.

How to disconnect the battery

Locate the battery and check which are the negative and positive terminals (there’s one of each). The former will generally have a negative (-) symbol and the latter, a positive (+) one. The power lead to the negative terminal may also be blue or black, and the positive one, red. If you’re in doubt, check the manual.

Put on safety goggles at this point because if the battery is faulty, it may have leaked acid.

Using a wrench to loosen the batter terminal clamp, remove the negative lead first and then the positive. For safety reasons, always remove the negative first, because if removing the positive lead first you could slip with the wrench and create a short circuit if. For example, is the tool touches the terminal and the car’s body it will short the battery, create a shower of sparks, and even electrocute you.

Once both clamps are released, tie them away from anything metal on the car.  It’s a good idea to label them as well so you don’t mix them up.

To reinstall the battery, connect the positive terminal first, followed by the negative. There may be a spark from the negative cable as you connect it but it’s normal and perfectly safe, unless there are flammable liquids or gas fumes close by.

Safety tip: Disconnect the battery’s negative terminal first but reconnect the positive terminal first.

Safe car service summary

To service your car safely you will want to:

  1. Use insulated tools if you’re working on the battery or charging system.
     
  2. Make sure the parts in the area you’re working on  – for example, the exhaust – are cold. Engine parts run at very high temperatures.
     
  3. If it’s possible, pull a wrench towards you, rather than push it to free a nut or bolt. This helps to avoid your hand hitting a solid metal part when it slips.
     
  4. When working on the fuel system, be extremely careful of any hot parts, open flame, or electrical connections in the vicinity.
     
  5. Always have a fire extinguisher to hand.