What is included in a timing belt check?
A timing belt check will involve a thorough inspection of the timing belt and its related components. These checks are particularly important to carry out on belts that are over 4 or 5 years old - because the timing belt is made of rubber, it will wear down over time and eventually break. When it breaks, the engine might stop running completely, or the components will be out of sync, causing serious damage to the engine.
Failing to replace the timing belt at the recommended time could result in engine failure, broken valves, cylinder head or camshaft damage, and cylinder wall damage, all of which are bad news for your wallet!
What does a timing belt do?
The timing belt, or cambelt, is a vital engine component with a key role to play in keeping your motor running smoothly. It ensures the top and bottom halves of your engine rotate precisely in time with each other. Essentially, this ribbed rubber belt with teeth synchronises the crankshaft and camshaft's rotation. It controls the sequencing and timing of the opening and closing of the valves on the cylinders in your engine to provide the right combustion.
Camshafts, made up of the main journals, the lobes (or bulges) and the ends, control the valves in the cylinder head. A rocker head takes the spinning motion of an overhead camshaft and turns it into the movement that opens and closes the valves.
Timing chains essentially perform the same function as cambelts but may be slightly noisier. The chains generally last as long as the vehicle (and generally require less frequent replacing), although the plastic guides they run over may not.
What causes the timing belt to break?
The main reasons a timing belt may break are its age and usage, or a failing water pump. Old age causes the materials to lose functionality, and overuse will wear a timing belt's teeth and tension. Contamination over time, from oil, water or other debris, can encourage deterioration. A failed water pump will seize the operation of the gears with such a force it can cause the timing belt to snap.
How do I know if my timing belt needs replacing?
Some common signs that your timing belt may need replacing are:
Engine is making a ticking noise
Engine struggles or fails to turn over
Rough engine idle
Engine misfires frequently
Drop in oil pressure or an oil leak
How long do timing belts last?
The lifespan of your timing belt is specific to your car and engine configuration, but is usually between 60,000 and 100,000 miles or 7 to 10 years. Because timing belts are made of rubber, they wear down over time and can eventually break. It’s therefore crucial that you have yours regularly checked for tears, splitting and general signs of wear to avoid the inconvenience (and expense!) of your belt snapping.
Is it expensive to replace a timing belt?
At between £200 and £500, it may seem like an expensive replacement cost. However, if you compare the cost to replacing your engine, which a worn or snapped timing belt can lead to, it seems like better value.
What happens when the timing belt breaks while driving?
The short answer is: It will damage your engine.
The long answer is: The camshaft stops turning, leaving some engine valves open. The heavier crankshaft continues rotating, causing pistons to crash into the open engine valves, bending or breaking them and possibly the cylinders. Damaged pistons and cylinders require the engine to be repaired or even replaced.
Will a broken timing belt badly damage my engine?
It depends on your engine type. There are 2 types of engine concerning this issue: an interference engine and a non-interference engine.
If your car has an interference engine then serious damage is highly likely. A non-interference engine is far less likely to suffer engine damage when the timing belt breaks.
Do you need to replace the water pump with a timing belt?
Your water pump has the same estimated lifespan as your timing belt. Although it's not imperative, it's highly recommended that both components are changed at the same time. Their operations are dependent on each other, and when replacing a timing belt, you have to remove the water pump to access it. There is no good reason not to replace one without replacing the other.
Does a new timing belt improve performance?
No. It can only restore the correct function, and timing, of your engine. It will improve your engine reliability, that's for sure, and you might sense your engine performing better if the old timing belt had become worn or loose. An incorrectly tensioned belt can lead to differences in your engine's timing. However, fitting a new belt won't improve your engine performance, only return it to its correct operation.
Can you drive with a broken timing belt?
No. Once your timing belt breaks, your engine will immediately stop running and turn off. Depending on which type of engine system your car operates with, will determine the amount of damage. Your engine won't start again, either way.
How long does it take to replace a timing belt and water pump?
Depending on your car and your mechanic, it can take anywhere between 3 and 6 hours to replace your timing belt and water pump. Given that you must remove the water pump to access the timing belt, and they both have the same lifespan, it's highly recommended to replace both at once. If you chose to replace both separately, you could end up paying almost double due to hourly labour rates.
