Monthly Archives: March 2015

Changing a Flat Tyre

To save space and weight, many new cars have a puncture repair kit which consists of sealant and a compressor, rather than a spare wheel.  If you don’t have a spare it’s a good idea to familiarise yourself with the kit provided so you’ll know what to do if you do get a puncture.If your car does have a spare it’s a good idea to practise changing a wheel at home in the daylight when the weather’s warm and dry, then if you do suffer a puncture you’ll be able to cope more easily, even if it’s dark, cold or wet. Check the handbook first as this might include vehicle specific advice if so follows the hand book advice. For your own safety don’t try to change a wheel on the hard shoulder of a motorway or at the side of a road. Turn off or pull over well away from the traffic and call for help. Don’t try to change a wheel on soft, loose or uneven ground. Don’t try to change a wheel with passengers still in the car, move everyone to a place of safety, well away from the vehicle and carriageway, don’t work under a car while it’s raised on a jack, don’t try to use the jack anywhere other than at the specified jacking points – attaching the jack in the wrong place can cause damage to the car and/or risks it collapsing when lifted. Before lifting the car, plan the job so that the vehicle is raised for the minimum amount of time, switch off the engine and turn on the hazard lights, apply the handbrake and engage first gear (or ‘P’ if an automatic). Secure the road wheel diagonally opposite the one to be replaced with a wedge, remove the spare from the boot/carrier – a carrier under the vehicle may be rusty and difficult to move, lay the spare on the ground where it will be convenient for fitting, remove the wheel trim (if fitted) – you may have to cut cable ties and/or lever the trim off, place the jack in the recommended lifting point closest to the wheel to be removed. Ensure that the jack head engages correctly (as shown in the handbook) and extend the jack until it just starts to lift the car on its springs. Don’t lift the car any further yet, loosen off the wheel nuts/bolts (most turn anti–clockwise to undo) using the vehicle’s wheel brace and locking wheel-nut adapter if required. (There might be a protective cover over locking wheel nuts, keep your back straight and body weight evenly distributed on both feet. When lifting the car raise the jack to lift the vehicle sufficiently so that the wheel is just clear of the ground, remove the slackened wheel nuts/bolts while keeping the wheel in position on the hub using a knee or toe – leave the top one until last so that both hands are free to lift the wheel away from the hub. Replace it in the carrier or boot well. If the spare is a temporary-use ‘skinny’ spare, note any restrictions on use – they’re typically limited to 50 mph and should be replaced with a normal tyre as soon as possible. Some dashboard lights may come on while a space saver spare is used because systems like ABS, traction control and some automatic gearboxes can be upset by odd tyre sizes. Check/adjust the pressure in the ‘new’ tyre as soon as possible. Get the wheel nuts tightened to the correct torque figure as soon as possible. Get the damaged tyre replaced or repaired as soon as possible.

Window Wipers

The first window  wipers were operated manually by moving a lever inside the car back and forth. Can you imagine having to do that nowadays? Today, most of us take our electric wind shield wipers for granted. The wipers keep the window clear, moving back and forth across the wind shield countless times as they sweep the water away. Wind shield wipers are found on car wind shields and some car headlights. The wipers combine two mechanical technologies to perform their task: A combination electric motor and worm gear (a gear consisting of a spirally threaded shaft and a wheel with marginal teeth that mesh into it) reduction provides power to the wipers. A neat linkage converts the rotational output of the motor into the back-and-forth motion of the wipers. It takes a lot of force to accelerate the wiper blades back and forth across the window so quickly. In order to generate this type of force, a worm gear is used on the output of a small electric motor. The output of the gear reduction operates a linkage that moves the wipers back and forth. Inside the motor/gear assembly is an electronic circuit that senses when the wipers are in their down position. The circuit maintains power to the wipers until they are stopped at the bottom of the wind shield, and then cuts the power to the motor. This circuit also stops the wipers between wipes when they are on their intermittent setting. The wiper blades are like squeegees. The arms of the wiper drag a thin rubber strip across the wind shield to clear away the water. When the blade is new, the rubber is clean and has no nicks or cracks. It wipes the water away without leaving streaks. When the wiper blades age or crack, road grime builds up on the edge and it doesn’t make as tight a seal against the window, so it leaves streaks. Wiper blades are designed to attach in a single point in the middle, but a series of arms branch out from the middle like a tree, so the blade is actually connected in six to eight places. If ice or snow forms on these arms, it can make the distribution of pressure uneven, causing streaks under part of the blade. If the wipers do not clean the window properly restricting the drivers view then this can be a failure on an MOT. Some wiper manufacturers make a special winter blade with a rubber boot covering the arm assembly to keep snow and ice out. Here at AE Services in Sutton we stock a wide range of wiper blades so if you are in need of replacement blades then book in now. For further details go to www.autoexpressservices.com.

 

What is a Coil?

An ignition coil is an induction coil in a car’s ignition system which converts current from the battery into the thousands of volts needed by the spark plugs to ignite the fuel. Like most car parts the ignition coils will not necessarily last forever and may need to be replaced at some point or other. This is not usually an overly expensive job and should take no more than a few hours to replace, getting you back on the road sooner rather than later. The coil that generates the high voltages required to create a spark is a simple device, basically a high-voltage converter made up of two coils of wire. One coil of wire is called the primary coil. Wrapped around it is the secondary coil. The secondary coil normally has hundreds of times more turns of wire than the primary coil. Current flows from the battery through the primary winding of the coil. The primary coil’s current can be suddenly disrupted by the breaker points, or by a solid-state device in an electronic ignition. If you think the coil looks like an electromagnetic you’re right, but it is also an inductor. The key to the coil’s operation is what happens when the circuit is suddenly broken by the points. The magnetic field of the primary coil collapses rapidly. The secondary coil is engulfed by a powerful and changing magnetic field. This field induces a current in the coils, a very high-voltage current (up to 100,000 volts) because of the number of coils in the secondary winding. The secondary coil feeds this voltage to the distributor via a very well insulated, high-voltage wire which in turn contributes to starting your car. Go to www.autoexpressservices.com for more information

Spark Plugs

The spark plug is an electrical gadget that fits into your cars cylinder head where it will spark, when you turn your key in the ignition, to ignite the fuel. The spark plug forces electricity to arc across a gap, just like a bolt of lightening. The electricity must be at a very high voltage in order to travel across the gap and create a good spark. Voltage at the spark plug can be anywhere from 40,000 to 100,000 volts. The spark plug must have an insulated passageway for this high voltage to travel down to the electrode, where it can jump the gap and, from there, be conducted into the engine block and grounded. The plug also has to withstand the extreme heat and pressure inside the cylinder, and must be designed so that deposits from fuel additives do not build up on the plug. Spark plugs use a ceramic insert to isolate the high voltage at the electrode, ensuring that the spark happens at the tip of the electrode and not anywhere else on the plug; this insert does double-duty by helping to burn off deposits. Ceramic is a fairly poor heat conductor, so the material gets quite hot during operation. This heat helps to burn off deposits from the electrode. Some cars require a hot plug. This type of plug is designed with a ceramic insert that has a smaller contact area with the metal part of the plug. This reduces the heat transfer from the ceramic, making it run hotter and thus burn away more deposits. Cold plugs are designed with more contact area, so they run cooler. The difference between a “hot” and a “cold” spark plug is in the shape of the ceramic tip. The engineer will select the right temperature plug for each car. Some cars with high-performance engines naturally generate more heat, so they need colder plugs. If the spark plug gets too hot, it could ignite the fuel before the spark fires, so it is important to stick with the right type of plug for your car. Here at AE Services in Sutton we recommend that the spark plugs are changed during a service which will usually be carried out once a year. Go to www.autoexpressservices.co.uk for more information.

 

What is the EGR Valve?

The EGR valve is vital to your car’s emission control; it controls a small passageway between the intake and exhaust manifolds. The EGR valve, or Exhaust Gas Recirculation valve, is a vacuum controlled valve which allows a specific amount of your exhaust gas back into the intake manifold. When the valve opens, intake vacuum draws exhaust gases through the valve. Exhaust Gas Recirculation helps to keep huge amounts of unburned fuel from being released into the atmosphere. This unburned fuel is thought to be a huge contributor to greenhouse gas build-up. The EGR valve helps your car run more efficiently and completely burn fuel by recirculating a portion of your exhaust gases and running it through the combustion process again. That’s why an EGR system became mandatory on all new vehicles some time ago. When the EGR valve malfunctions, it must be replaced. Unlike some emission control devices that can malfunction without affecting the performance of the vehicle, a faulty EGR valve can really affect the engine’s performance, or even cause it to stop running altogether. This exhaust gas mixes with the intake air and actually cools the combustion process. Cooler is always better inside your engine. The exhaust gases that your EGR valve recirculates also prevents the formation of Nitrogen related gases. These are referred to as NOX emissions, and are a common cause for failing emissions testing. Unfortunately, your EGR valve can get stuck, causing NOX gases to build up. You’ll know if your EGR valve is stuck or malfunctioning because your car will experience symptoms like rough idle and bucking on acceleration. EGR valves do not normally require maintenance or replacement for preventative maintenance, but the valve can become clogged with carbon deposits that cause it to stick or prevent it from closing properly. Dirty EGR valves can sometimes be cleaned, but replacement is necessary if the valve is defective.

When Will My Tyres Need Changing?

If you notice deterioration in the performance of your vehicle this could be a sign that your tyres need changing. If your car does not handle or grip the road as well as it should in poor weather conditions as it normally does, or it takes longer to stop when you apply the brakes this could indicate that your tyres have worn.  Tyres wear gradually and this can make it difficult to identify the reduction in performance, so it’s best to have them checked regularly and preferably by an expert. It is the driver’s responsibility to ensure that the tread on your tyres is not worn beyond the legal minimum limit of 1.6 millimetres. Tyre manufacturers mould tread wear indicators into the design of the tyre tread pattern usually at a tread level of 1.6 mm. As soon as the tread is worn to the height of the tread wear indicator, the tyre has reached the legal minimum tread depth and you should replace the tyre as soon as possible. You should also be aware that there are many different reasons for tyre wear. Your tyres don’t just get worn through age and use, but through emergency braking, under-inflation or over-inflation. And if your wheels are misaligned, one edge of the tyre can wear more rapidly than the other edge. Here at AE Services in Sutton we recommend a weekly walk around the car to check the tread, look for bulges or wear and to check tyre pressures every time you fill the tank. Our service package includes an inspection on your tyres which is then is recorded on the service schedule sheet so you know the condition of the tyres and any comments the engineer has made. Go to www.autoexpressservices.co.uk for more information.

 

What is an Air Filter?

Any engine that runs by internal combustion of fuel requires air to operate. That’s because without air, specifically oxygen fuels like gasoline and diesel can’t burn and provide the explosive force to power the engine. In modern vehicles, the air must be cleaned before it gets sucked into the engine’s air intake plenum and combustion chambers. If not, you run the risk of dust, dirt and debris quickly fouling up the engine, causing poor performance and potentially shortening the life of the car. Foreign particles act as abrasives on the metal parts of an engine, wearing away at engine bearings, piston rings and cylinders. In addition, modern engines rely on a precise ratio of air to fuel. When the engine is starved of air, the fuel mix will run too high which in effect puts added strain on the engine. Fortunately, we have engine air filters which allow just the right amount of air through the vehicles engine, while trapping the grit that would do our engines harm. But even the best air filter can withstand only so much abuse from the outside environment. So how do you, as a car owner, know when it’s time to change the air filter? That all depends on the usage and what conditions the car is driven. If the car is used in dusty, harsh conditions (think of stop-and-go city driving with lots of construction going on), then more frequent air filter changes are in order. If, on the other hand, you happen to be a weekend driver only, you can get away with less frequent air filter replacements. Your best bet, of course, is to consult the owner’s manual. All of our customers here at AE Services in Sutton will receive a free reminder as to when the next service is required on their vehicle. For further details go to www.autoexpressservices.co.uk

Common MOT Failures

Time for your MOT? Here are a few things you can check before you take your car to the garage for a MOT. All external vehicle road lights must be in working order, even the number plate bulbs will fail if not working! If your tyres are below 1.6mm on the tread this is a MOTfail, the spare tyre is not checked. Check your screen wash level & your wiper blades, they must clean your windows properly, if you’ve got the bonnet open, then it closes & locks that’s another check done as these are MOTfailures too! There are certain dash lights that will fail the MOT, these are Airbag Light, Amber Brake Light, ABS & ESP Light. Are all of the seat belts working? Pull them out & plug them in, if they do not click in & stay then this will fail the MOT. Check all doors open and close as this is an important safety issue & will fail the MOT! Honk your horn, if it’s working great, if not that’s a failure! The emission test is to check the gasses coming out of the exhaust these can be affected by poor vehicle maintenance, sensor malfunction or a hole in the exhaust, all of which can be repaired at our garage AE Services in Sutton. A few things you can’t check on your vehicle that can fail during a MOT: Steering arm, track rod ends, wishbones, tie rods, CV gaiters, CV joints, shocks, road springs, drop links, D rubbers, ball joints fueling system, brakes, chassis corrosion, head light aim, severe dangerous oil leak. If you MOT fails we can carry out the repairs need to pass your MOT and this can be done on the same day. Don’t worry, If you feel you are not confident in checking these yourself you can get them checked with our garage if requested before your MOT is due. At our garage in Sutton we offer a FREE text or email MOT reminder service.

My Car Won’t Start!

There are many reasons that a car may not start.  A dead battery is one of the most common reasons. Usually, you can hear a clicking noise but the car won’t start. When a battery dies or loses its charge, it also loses its electrical power. That prevents the battery from supplying the electrical power needed to start the vehicle. The car may crank over, but still won’t start. The fuel supply to your engine will need to be checked. An engineer will check to make sure that the electrical spark is getting to your spark plugs. While an alternator is a relatively simple component containing only a few parts, it plays a critical role in any vehicle’s operation. Essentially it turns the mechanical energy of the engine’s rotating crank shaft into electricity through induction. Wires within the alternator cut through a magnetic field; this in turn induces electrical current. That current is used to power your car’s accessories, e.g. headlights. The alternator also keeps the battery fully charged, providing the power it needs to start the car this is also a common item that could need replacing. A bad ignition coil can prevent electrical power from a vehicle’s battery from reaching the engine spark plugs. If the car is silent when you turn the key in the ignition, you will need to have the battery terminal connections checked the cables may need cleaning or replacing.  A starter motor is responsible for turning a vehicle’s engine and forcing the pistons up and down. When a starter motor fails, it lacks the strength to turn the vehicle engine on. A blocked fuel filter can prevent fuel from flowing into a vehicle’s engine, and that can prevent engine combustion. A fuel pump is responsible for pumping fuel from a vehicle’s fuel tank into the engine so the spark plugs ignite the fuel and cause an engine to start and run. If the fuel pump loses its fuel pumping ability, your car won’t start. All of these possible starting issues can be checked out here at AE Services in Sutton by one of our fully qualified engineers.

What Tyres Should I Get For My Car?

Buying tyres for your car as with most things is easy if you have access to the internet and you have some knowledge of the different tyre makes and sizes available. It is also mind boggling for those of us who do not have a clue about which tyre to buy, so here is a brief guide to the differences between tyres.

The most commonly used tyres and the cheaper option for those of you watching the pennies are a budget range tyre starting at around £30 plus vat each, Event, Nexon, Maxus, Kenda, and Sunny to name a few. The public will not be as aware of these make of tyres as they are of say Avon and Goodyear which is reflected in the price. The budget range are recommended for around the town driving so if you are only driving your car to the supermarket, taking the kids to school, basically A-C driving then budget tyres are all you need.

Mid-range tyres are the next option for those happy to spend a little bit more. The obvious difference apart from cost is that the mid-range tyre will last longer than a budget, depending on the driving. Firestone, Bridgestone and Goodyear manufactured in more recent years are a few of the makes that we supply to our customers here at AE Services in Sutton requesting a mid-range tyre. Prices will generally start at around £45 plus vat each. The mid-range tyre will be recommended for those who do the occasional motorway journey as well as around the town driving.

For those drivers where money is not an issue, the make of tyre is of importance or you are an everyday motorway driver then a premium tyre is what you are going to need. The price is usually higher in the premium range as they will be manufactured by well-known companies that have been making and selling tyres of great quality for many years. Continental, Dunlop, Michelin and Avon are the commonly used premium tyre here at AE Services in Sutton and vary in price considerably starting at around £60 plus vat, going up to and over £90 plus vat.

Vehicle tyre sizes are normally shown in the form ‘195/65R 15 91W’. You can find this size on the side wall of your existing tyre, or in the vehicles handbook.The first number, in this case ‘195’, is the width of the tyre at it’s widest point, in millimetres. The next number, shown here as ’65’, is the ratio of the tyres side wall height to the width of the tyre, shown as a percentage. In this case the side wall height would be 65% of the width. The “R” stands for radial, if there is no letter then it is a cross ply tyre. The third number after the R, in this example ’15’ is the diameter of the wheel the tyre is designed to fit, in inches, tyre sizes are a combination of metric and imperial units. The next part, ’91W’, denotes the load and speed ratings. The number is the load rating and the letter is the speed rating.