The timing belt in your car is one of the most important but often overlooked parts of your engine. It is a rubber-like belt that has teeth on the inside which connects the camshaft of your engine to the crankshaft. Like every part of your engine the timing belt reqauires some maintenance and upkeep every now and then to ensure that everything runs as smoothly as it possibly can. And while you probably know that you need to change your oil every 3,000 miles to 5,000 miles, and you might need to change your transmission fluid every 90,000 miles or so, not everyone realizes when is the right time to switch out a timing belt. It's also possible that you might be avoiding getting your timing belt looked at because you've heard it can be an expensive repair. While this is true, a broken timing belt can cause much more damage and bring with it much higher repair bills. That's why it's recommended that you change a timing belt every 60,000 miles to 100,000 miles.
What is the Timing Belt?
As we said, a timing belt is a rubber-like belt that has teeth on the inside of it. Many people will refer to it as a rubber belt, but they are often made of reinforced materials and embedded with nylon thread that also helps improve the strength and resilience of the belt.
Inside your engine the timing belt connects the camshaft and the crankshaft. As the crankshaft spins the pistons in your engine pump up and down into the cylinders and valves. The camshaft in your engine is what is responsible for opening and closing the valves.
The timing that the timing belt refers to is the precise time that these two shafts need to rotate in order to work together to allow your engine to burn the fuel and air mixture in the combustion chamber at the exact right moment, thus creating the power to move your entire vehicle. The camshaft must open the valves of the exact right moment to allow the pistons to rise up thanks to the crankshaft.
If you have what is known as an interference engine, you can get disastrous results if the camshaft and crankshaft are not in perfect alignment. In an interference engine, when your timing belt slips the camshaft will stop moving, the valves will remain open or closed, but the pistons will keep moving with the crankshaft. That can cause the pistons to hit the valve openings, slam into the sides of the cylinders, warp, break the cylinder heads, and more.
When your timing belt isn't working properly, the combustion reaction is not happening when it's supposed to. That means it could happen too early, too late, or not at all. That's going to greatly decrease your engine's efficiency or make it so that your engine won't work at all. Regardless of the severity, when the timing is off, you're definitely going to be suffering performance issues as a result. The longer this is allowed to continue the more likely you are to suffer serious engine damage. When the timing belt breaks, and the pistons end up hitting and breaking the valves in the cylinder your repair bills can end up costing upwards of $4,000 to $5,000. That's why it's of the utmost importance to make sure your timing belt is changed before it fails completely.
Can a Timing Belt Last 200,000 Miles?
As technology improves, the timing belts in cars are made better and better all the time. Many modern vehicles have actually swapped a timing belt in favour of timing chains again, the same sort of metal chains that used to be used in vehicles back in the 50s and the 60s. A timing chain is much stronger and will last much longer than a timing belt.
Many vehicles still do have timing belts in them, and you need to know the condition of yours if you hope to keep it in good working order. While the recommended timing for a belt change in most vehicles is between 60,000 miles and 100,000 miles your best bet is to check with your owner's manual to know for sure exactly when yours has to be changed.
Every manufacturer has a precise recommendation in the owner's manual for when you should be checking your timing belt and getting it changed. If you no longer have access to the manual you can Google it and find out for yourself.
There are many drivers who are willing to push a timing belt as far as it can go. It's not unreasonable to inspect a timing belt at 100,000 miles and see that it's still in relatively good condition. Like we said, these things are manufactured to be tough, and if you don't push your car too hard and engage in other routine maintenance to keep your car working as well as it can, it's very possible that your timing belt could be in good condition even after 100,000 miles of use.
As for the question of whether or not a timing belt can last 200,000 miles, that's really a mixed bag of answers. There are many forums online in which drivers discuss how long timing belts have lasted. Some drivers have had timing belts that lasted 200,000 miles while others have claimed 230,000 miles, 250,000 miles, and some even almost got to three hundred thousand miles on the same belt. That's even longer than the recommended lifespan of a timing chain.
So, is it possible that a timing belt could last for 200,000 miles? Absolutely. Should you expect yours to last that long? Absolutely not. Every mile you drive beyond the recommended distance for getting your belt changed is a risk that it's going to fail sometime soon. Obviously if you had a mechanic inspect it and have seen that there's very little wear, all the teeth are still present, and it hasn't been stretched out at all then it's very likely that it will still serve you for a while to come. But having a timing belt in that good condition after that much time is exceptionally unlikely.
Of course it's up to you how long you want to push your timing belt past the recommended changing date, but just be aware that you're basically on borrowed time and make sure you frequently take a look at the bells, give it a visual inspection to see how it's doing, and make sure it's still in good working order so you don't get surprised by a break. As we said, when a timing belt breaks the damage it can cause is extreme. It's also remarkably fast. The moment a timing belt breaks in an interference engine, your engine will suffer extreme damage. If that happens while you're driving, you'll be stranded on the road with a very expensive repair bill on your hands.
How Do You Know When a Timing Belt Needs to be Replaced?
The natural lifespan of a timing belt is not the only way to know when it's time to change the timing belt. There are signs of a bad timing belt you can be on the lookout for that will let you know it's time to change it before you reach that 60,000 to 100,000 miles if something has gone wrong. Or, after the 100,000 mile limit, if you’ve still been using it but the performance of your vehicle has begun to suffer as a result. Be on the lookout for these signs and symptoms of a bad timing belt to know when to get yours inspected.
Timing Belt Noises
Your timing belt makes a distinctive sound when it starts to go wrong. Obviously there are a number of sounds you should be used to that come from your car when it's in motion, but this sound will be distinct and is a good way to alert you to the fact that something needs to be done. When your timing belt begins to fail it will start producing a clicking or ticking sound as it runs. This is very fast-paced noise, but it will also be distinguished from most any other sound that you're used to in the engine of your vehicle. If you hear this clicking sound, which is not unlike a spinning roulette wheel, it's a sign that your timing belt may be about to fail soon.
Engine Won't Turn Over
This is what will happen if the timing belt actually breaks in your vehicle. That said, this is the best way that your timing belt can break, on vehicle start up in such a way that you're not actually able to get the engine going. The reason this is a good thing, if you belt has to break, is because it definitely minimizes the damage to your engine as a result.
If the timing belt in your engine begins to wear out it will not be able to keep the camshaft and the crankshaft in perfect synchronous operating order any longer. When that happens, you're going to get the combustion reaction happening at the incorrect time. The fuel and air mixture injected into the chamber won't happen when it's supposed to and that means your combustion reaction can be happening too early, too late, or not at all. When it doesn't happen at all in one of the cylinders that's an engine misfire. You will suffer poor engine performance as a result losing power equal to the chamber in which the misfire occurred. That just means that if you have a four-cylinder engine and one chamber misfires you lose 1/4 of the power of your engine.
Oil can begin leaking under the timing belt cover if the gaskets between the engine block in the timing cover of worn out, or if the bolts sealing it in place have become loose. If oil ends of leaking onto the timing belt itself it can cause it to much more easily slip off the year at the end of the camshaft for the crankshaft, as well as degrade the belt so that it wears out faster.
If the teeth come loose from the inside of your timing belt they can fall into the gears, or if enough of them slip off then the belt itself will not have a smooth run between the camshaft of the crankshaft gear. The result of that can be some serious rough idling which causes your car to vibrate and shake, even if you're just sitting still in it.
Bad Oil Pressure
If the teeth break off your timing belt, they're most likely going to fall down below into the oil pan since it's located under your engine, and under the belt. If several teeth break off, they can actually get clogged in the oil pan and prevent oil from circulating properly through your engine. That's going to lower the oil pressure overall and lead II engine overheating as well.
The Cost of Replacing a Timing Belt
Unfortunately replacing a timing belt is not a particularly cheap repair job. Because of where the timing belt is located in your engine it does take some effort to get too. A mechanic is going to take a few hours to get this job done for you depending on the make, model, and year of your vehicle. The result of that is the repair itself can end up costing anywhere from $500 on the low end of the scale all the way up to a potential $2,000 or more. This is why a lot of drivers will see how far they can push a timing belt because it's a remarkably expensive repair job, but it's one you absolutely can't avoid at some point in time. Your car simply won't run without the timing belt, and the repair cost is one that you're going to have to endure at some point in time.
The Bottom Line
The precise timing of the combustion reaction in your engine relies entirely on the ability of the timing belt to do its job. You could argue it's one of the most important parts of your engine, if not the most important part to keep it functioning properly. It's expensive to repair when something goes wrong, but it does need to be done. Check out your owner's manual to find out the exact time that your timing belt will need to be changed and remember that it's likely to be somewhere between 60,000 miles and 100,000 miles. If you want to stretch it further, you do so at your own risk.