Learn About Your Car - Reasons Why Your Cam Belt Fails
Welcome to another blog from your local mobile mechanics in the North West and North Wales area. Fl mobile mechanics are dedicated to showing you how and why so you can better understand the job we do, the transparency of our company, and our dedicated vehicle repair service and service to you. In this blog, we're learning about timing belts and how they can go wrong, what can happen to your engine, and ultimately what it might cost to put them right. Year after year our dedicated
North West and North Wales mobile mechanics take care of vehicles and offer preventive maintenance to stop major failures like this from happening. Remember, prevention is better than cure. Remember, our mobile mechanics have years and years of experience and we are here to help. If you have had a timing belt fail on you, call us directly on 0300 124 6980.
If a vehicle’s timing belt fails, it usually leave the driver stranded on the side of a road needing a tow. A broken timing belt may also mean thousands of dollars in engine damage and repair bills! With the help of FL mobile mechanics, We've put together a list of possible causes as to why your car or van's timing belt has failed. Hopefully, this will help you identify the reason for a timing belt failure. Visually examine your timing belt drives for these top 9 failure-causing problems and it could help to prevent your drive grinding to a halt, avoiding unscheduled downtime. The most common thing that's going to happen if your timing belt fails while you're driving is that the valves are going to get bent. There's also the potential for the cylinder head to be damaged and the camshaft to be damaged as well, and you could end up the damage to the cylinder walls, the Pistons, and more. For in-depth advice or a quote, call us now on 0300 124 6980.
Why do timing belts break?
There are a few common causes for timing belt failure. These include failure due to age, tensioner, and pulleys. But let's look at this in more depth.
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Age and miles - The timing belt is usually made from a rubber material with teeth on one side to control the gears, pulleys, and components in the engine. With the heat and friction inside the engine, the rubber material will become worn with age and miles.
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Rubber teeth -These may wear down and no longer be able to grip the gears. This often results in a slip of the timing belt and potential damage to the engine.
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Cracking under stress - The timing belt may also begin to crack under stress. As the material cracks, it’s at higher risk for snapping and breaking in the engine.
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Water Pump Seizure - Timing belts run through the water pump, which means it’s at risk should something go wrong with the water pump. When the water pump seizes, the gears stop turning with a strong force that will almost always break the timing belt. Water pump seizure is often caused by a problem with the cooling system, ignoring coolant flushes, or missed maintenance for the cooling system.
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Damaged or worn pulleys - Damaged or worn timing pulleys will substantially reduce belt life. Worn teeth will cause belt wear and/or damage. Nicks or gouges can cut the belt. Inspect and replace pulleys that show signs of wear
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Debris in the timing pulley or drive - It’s the most overlooked, but debris can cause a multitude of problems for your timing belt & pulley. Dirt on the teeth can abrade the belt and oil can attack the belt materials. Use a stiff brush to clean off rust and dirt. Wipe clean of oil and grease. Debris can account for any of the above reasons for timing belt failure – so go clean those pulleys and fit a shield to that drive!
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Excessive load - If the timing belt teeth are shearing, excessive load is more than likely the cause. Tensile failure and even excessive tooth wear can also be caused by excessive load or shock loads, although the latter is less likely. To cure this problem you’re going to have to redesign the drive.
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Under-tensioned Belt - Tooth skipping, also called ‘ratcheting’, is probably down to your belt being under-tensioned. Under-tensioning can also cause excessive or uneven tooth wear and excessive drive noise so use a tension gauge to set the correct tension on those timing belts!
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Engine misfiring – as a worn out cam belt can play havoc with the engine's firing sequence. Slips will cause cylinders to open and close too early or too late. Such problems can cause the engine to fail if left unchecked.
Remember, A timing belt will eventually fail by loss of teeth in what’s considered normal wear, any other failure reason should be considered abnormal. This list of possible failures can show why it has happened. But then there is getting it repaired, and that's where we come in. Consult our Timing Belt Repair specialists. We are based in the North West and collect vehicles with snapped timing belts from across North Wales, the North West, and many other parts of the UK. With our fast turnaround and collection and drop-off service we really are leading the way in timing belt repairs.
To the bigger question of why a timing belt has snapped
Asking why is one thing, but a question what is missed out a lot when repairing a timing belt on a vehicle is what damage could this have caused? We can tell you from our own experiences and the number of timing belts we have replaced, repaired, and vehicles we have brought back to life, it Varys. Sometimes you can be really lucky and no damage will be caused. however, sometimes further damage can have been caused. More often than not, you will find that bent valves are an issue in getting your engine running again. In some cases, we have seen valves go through the piston head, and then you are into an engine rebuild.
Let's take a look at what the possible outcomes are below
- Bent valves
- Piston head damage
- Bent con rods
- Damaged crank
The cost of all of this?
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Damaged vales the repair cost - Since the valves in your engine are the most likely to get damaged when your timing belt fails, it's worth knowing what you can be looking at in terms of repair causes this happens. On average, the cost of repairing so damaged valves in your engine will be somewhere between £120 and £3200. The make, model, and year of your vehicle will heavily determine which end of the spectrum you're on in terms of this particular repair bill.
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Damaged piston repair cost - If the pistons are damaged in your engine, you're also looking at a fairly steep repair bill to fix it. Replacing the piston rings in a car can cost anywhere from £300 and £3000.
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Damaged camshaft repair cost - If the camshaft of your vehicle suffered some damage as a result of your timing belt failing, then you can expect a repair bill that's going to be around £1200 to £4000 to get it replaced.
It's also possible that if your timing belt were to snap while you're driving you could have a one-in-a-million chance to suffer no damage at all just because the timing was so lucky. this is definitely not the kind of thing you want to bet on though because it's almost completely unheard of.
While there are a number of ways that your timing belt can fail if your timing belt breaks while you're driving your car it could be extremely dangerous and destructive for you depending on exactly what transpires. It's worth noting that there is no grace period when it comes to a broken timing belt. The damage it causes is absolutely immediate and once the belt breaks there is nothing you can do to prevent it. It will happen at that moment no matter where you are. If you're in the driveway, if you're driving down the highway, the moment your timing belt breaks the damage that's going to happen will occur right then and there. This could cause you to lose power and stall out right in the middle of a highway if that's where you are, or leave you stranded in a parking lot.
The chances of no engine damage when your cam belt snap
Interference vs Non-Interference engine - The effects that a broken timing belt will have on your engine very much depends on whether you have an interference engine or a non-interference engine. There are many different designs for engines in vehicles, but there are some general ways you can tell the difference between an interference engine and a non-Interference engine.
In specific, the big difference between these two types of engines is the way the valves open. An interference engine is a 4-stroke engine that will open one or more of the valves to accommodate the piston as it rises through the cylinder. In a non-interference engine, the pistons don't go into the open valve and this difference is absolutely key to what happens when a timing belt fails.
The timing belt synchronises the camshaft with the crankshaft. So, if you have an interference engine and the timing belt fails, the camshaft is not turning, and the valves will not open. The piston will still rise into the cylinder and then it will collide with the closed valve. This could damage the cam heads, the valves, and the pistons, and essentially destroy your entire engine.
If you have a non-interference engine and the timing belt fails, because the piston never enters the valve even when it's operating normally, you are not suffering the same damage that you would with an interference engine. That doesn't mean that your engine will continue to function because it won't, but the damage that is caused to it will be greatly reduced.
This may make you wonder why anyone uses interference engines in the first place. If an interference engine is at risk of such serious damage when a timing belt fails, and a non-interference engine can still do the same job, why use interference at all? That's because the compression ratio in an interference engine is actually much better than a non-interference engine. The compression ratio relates to the volume of the combustion chamber. In an interference engine, you have a far superior compression ratio which allows for increased performance and better fuel efficiency.
Essentially the choice between an interference engine and a non-interference engine is a bit of a gamble on the manufacturer's part. They are banking on the improved performance of an interference engine outweighing the potential disadvantage of a critical failure with your timing belt. Of course, if you properly maintain your timing belt you greatly reduce the chances of that kind of failure and it may work out all right. Unfortunately, you can't always account for everything and sometimes even when a timing belt is still well within its projected lifespan it may fail and that can cause serious problems for your engine.
Warning signs of a bad timing belt
In order to prevent the serious damage that can happen when your timing belt breaks while you're driving, there are some warning signs that you can be on the lookout for a head of time to let you know you should get your timing belt replaced. The first thing you can do is actually check your manufacturer's recommendations for when your timing belt needs to be replaced. It should be listed in your owner's manual, and typically you can expect to replace the belts between 60,000 miles and 90,000 miles. Some manufacturers will recommend a change at about 105,000 miles, so it really is something you should look up to know for sure. These are just recommendations, but they are the results of the manufacturer's experience with their own vehicle, and they're definitely something that you should keep in mind.
Noises coming from your engine?
The noise your cars engine is making is always a good indication of something being wrong that you need to be aware of. The sound your car makes when it's running normally is hopefully something that you are familiar with. When something starts making a new sound, then you can look into the source of it so you can figure out what's up and do something about it.
In terms of your timing belt there is a distinct ticking noise that it might make as it starts to wear down. It's a very repetitive, fast-paced noise and it's unlike any other noise that your engine would normally make so when it starts, you should have no problem identifying it and realizing that there is an issue with your timing belt. The sound is not unlike someone spinning a roulette wheel very quickly.
There's also the potential for your timing belt to make a squealing sound as it begins to fail. The squealing sound of belts going wrong is not unique to timing belts, but if you hear a squealing sound on an intermittent basis it may be the timing belt struggling. This can happen for any number of reasons including acceleration or even braking.
Engine misfires and what they mean?
Because the timing belt is responsible for maintaining that precise timing as it begins to go bad, the timing in your engine is going to be thrown off. This can manifest as serious engine misfire. Because the timing belt isn't able to keep the camshaft and the crankshaft exactly synched the way they're supposed to, you run the risk of your valve opening and closing at the wrong time, or the fuel pump injecting the fuel into the chamber when it's not ready for it anymore. This can cause spark to happen at the wrong time, or not at all. If there is no combustion in the cylinder on one of the strokes, then you're having a serious misfire and you will lose proportional power. Continuous engine misfires can lead to damage to your engine as well as reduced performance and reduced fuel economy.
Is your car idling rough
This is a problem that can stem from a number of different causes in your vehicle, but a faulty timing belt can be a contributing factor that you need to be aware of. When you're experiencing rough idling, it means that your car is vibrating and shaking as though the engine is struggling, even though you're not pushing it all. When you turn on your car and the engine starts running and you haven't even started moving yet, it will seem like the engine is having a rough time and it may shake enough that you can feel it in the cabin. This is rough idling, and it is definitely something that you want to get looked at before it becomes too big of an issue.
Has your car got an oil leak?
Oil can begin leaking from around the timing belt cover if the nuts and bolts begin to loosen. You'll be able to see oil on the driveway in front of where the engine sits when this happens, and you may also be able to see it inside the engine. The problem in terms of your timing belt when this happens is that, if it's leaking inside the engine belt cover, then you may end up with oil on the timing belt which can cause it to wear down much faster. There's also the potential for the teeth to come off your timing belts and, since your timing belt is above the oil pan in your vehicle, the teeth can fall into it and plug the pan. When this happens, the oil is not able to circulate properly any longer, so you risk that lack of lubrication in your engine which can lead to overheating.
The facts are...
Until we strip it down we will never really know the true cause of the damage. And as much as Fl mobile mechanics love to be transparent and straightforward, we simply cant tell you what the out come would be until our expert mechanics get into the internal workings of your engine. In fact, no one can tell you and if they can, they are just guessing! Your engine is a metal object that no one can see through. Even though a timing belt is a seemingly simple piece of technology, it does an extremely important job and if you push it to the limits you risk breaking it while the car is in motion. Once your timing belt breaks while you're driving there is nothing you can do to fix the problem any longer. The potential damage to your engine will be severe and very expensive. For that reason, you never want to ignore the warning signs that something is going wrong with your timing belt. As well, you need to be aware of the manufacturer's recommended lifespan of any timing belt. If your owner's manual says your timing belt should be changed at 60,000 miles and you've made it to 80,000 miles, you're driving on borrowed time. There's a good chance that if you're already experiencing any of these signs of a bad timing belt that it's not going to last much longer for you.
How can you protect your vehicle and your family
Preventive maintenance with Fl mobile mechanics - The best thing you can do for your vehicle is keep up with preventative maintenance! Coolant flushes are designed to keep the cooling system operating its best and catch problems early (before they cause a water pump seizure). Regular inspections may catch signs of wear and tear on the timing belt early. Check your manufacturer’s maintenance schedule
If you buy a used car
If you’ve ever bought a used vehicle, you’ve no idea of its history. Fl mobile mechanics recommend getting your timing belt changed to ensure nothing detailed in this blog happens to you! This again is part of our preventive maintenance campaign and understanding your car so that we can take care of it better for you. Many people say you should know when the timing belt was last replaced before you purchase an older vehicle. Unlike a serpentine belt or a fan belt or auxiliary belt as it’s also known, a timing belt is not visible when you pop the hood. However, there are still ways you can tell when it’s time to change out this critical engine belt. Remember you can book us to sort all these issues for you online or over the phone. For any advice you need, call us today on 0300 124 6980
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