by The most common answer to this question is — according to the manufacturer’s recommendations. But there’s a nuance — it’s by recommendations not for the model, but for the specific engine. What other nuances should you know and what should you consider to avoid a timing belt breakage? Specialists from the online store Leoparts have shared their insights.
Why is the Timing Belt Needed and Why Should It Be Changed
TIM (Timing) is an abbreviation for the term “timing mechanism”. It refers to the system of components inside the engine responsible for delivering the fuel mixture to the cylinders and also for removing exhaust gases.
What does the belt do in this system? It synchronizes the operation of the crankshaft and the camshaft (or two, depending on the engine design). Both of these parts end with gears to which the timing belt is attached. Thanks to the belt’s operation, the valves and pistons never touch inside the cylinder. This task is important, so the belt must be perfectly tensioned — this is the job of the tensioner. There are also idler pulleys in the design — they are needed to “pave the way” for the belt in the engine compartment. In some cars, the timing belt also drives the water pump (impeller).
By the way, sometimes the chain performs the same function as the timing belt. A timing chain lasts several times longer and is considered a more reliable design. But it’s more complex to replace. Therefore, both the part itself and the service at the repair shop are much more expensive.
What Will Happen If the Timing Belt Breaks
Considering its main task, a timing belt breakage is a situation you should never allow. Because unsynchronized camshaft and crankshaft begin to rotate independently of each other. As a result, valves quickly “meet” pistons.
The least that awaits such an engine is bent valves, which are the least durable of all parts. Piston bottoms can also break — either directly from the impact or from valve debris. In general, the higher the RPM was at the time of breakage, the more serious the consequences. And the more expensive the repair. Up to an engine overhaul.
For diesels, things are even more complicated and “injurious” for the engine. Due to design features, the camshaft, its bearings, and connecting rods are often damaged.
That’s why it’s important to regularly check the condition of the TIM and change it timely.
The Timing Belt Replacement Schedule
The first option is based on the car’s mileage, in accordance with the manufacturer’s recommendations for your specific engine. The numbers vary greatly.
For example, for diesel engines of the VW Passat B6 1.9 and 2.0, the timing belt is changed every 90,000 kilometers. The same resource applies to the Skoda Octavia A6 with 1.4 and 1.6 L gasoline engines. And the timing belt in the Ford Focus 2 with a 1.6 L gasoline engine — even after 160,000 km. Renault Megane 3 1.5 dci owners are lucky too — their timing belt requires replacement every 150,000 kilometers.
But there are opposite examples, with shorter distances. For instance, in a Chevrolet Lacetti with a 1.8 F18D3 engine, the timing belt needs to be changed every 60,000 km. And in a car like the VAZ-2112, every 50,000 kilometers.
The second option is based on the “age” of the belt if the mileage is very low. The average calculated mileage of a car is 20,000 kilometers. If your car drives much less (for example, 10 thousand a year), then divide the manufacturer’s recommendations by 20,000 — this will be the number of years after which the belt should be replaced. On average, this is 5-7, maximum 8 years.
The third option is considering challenging or intensive operating conditions. If the car works as a taxi or frequently drives a lot, the belt’s resource decreases due to constant work and overheating.
How to Check the Timing Belt
Many manufacturers, besides the replacement interval, also have recommended mileage for checking the timing belt condition. In fact, this can be done at each maintenance service or during work in the engine compartment.
What Needs to Be Checked?
- Inspect the belt for cracks and fraying.
- Check for traces of oil or antifreeze.
- Assess tooth wear.
- Check the tension/stretching of the belt.
Why It’s Better to Change the Timing Belt as a Set
An important nuance in replacing the timing belt is that it’s better to change it along with a set of all the rollers and tensioners that work with it. Why so?
There are two main reasons.
The first — replacing the timing belt as a set is better for saving on labor costs. No roller lasts as long as two belts. And in most modern cars, changing the timing belt is a labor-intensive process. The cost of the set is less than the cost of labor.
The second — assessing the wear of the rollers is quite difficult. And a seized roller can lead either to reducing the belt’s lifespan or even to its breakage. That means you risk being a hero of the saying “a penny-pincher pays twice.”
So if you tinker with your car yourself and regularly inspect everything, you can take a risk. But if you, like most car owners, go to the repair shop to change the timing belt and trust your mechanics for control, then you should change it only as a set.
