What is a timing belt and when should you get it replaced?

timing belt, or cambelt, keeps essential components of your car engine (the camshaft and crankshaft) working in sync. The reason the timing belt is so crucial is that any slight disruption to the synchronicity of these components can be disastrous for your car engine.

Your engine’s camshaft lets fuel and air in and out of your engine, while the crankshaft moves the pistons up and down simultaneously. It’s vital that they work together in perfect harmony. The cambelt ensures the two are always aligned. It’s crucial that you have your cambelt replaced at the manufacturer-recommended interval.

What's the difference between a cambelt and a cam chain?

Some vehicles are fitted with a timing chain or cam chain instead of a belt. Cambelts are made from rubber composites, whereas cam chains are made of steel and drive sprockets, not dissimilar to those on a bicycle. Cam chains generally last longer due to their strength and lubrication.

If you’re unsure whether your vehicle has a cambelt or a cam chain, check your vehicle handbook.

When to change a cambelt?

Timing belts are always replaced depending upon the interval, whether that be mileage, age or both, as determined by the vehicle manufacturer. These timings are also subject to change if a manufacturer updates the intervals based on technical recalls./

How do I know if my cambelt needs changing?

Sometimes, your cambelt may need replacing earlier than expected. There are a few signs to look out for:

Engine noise

Listen out for any odd noises coming from the engine. If a cambelt is about to fall, there will be a rubbing sound coming from the engine area. If you hear this sound, turn off the engine and get it looked at by a professional as soon as possible.

Car isn't starting

There are a few reasons why your car may not start but one of them could be an issue with the cambelt. If your car doesn’t start and you suspect this could be the case, call your breakdown service.

Why has my timing belt broken?

There are a few causes of a broken timing belt but a common cause is failure to replace within the recommended interval. Another reason could be from ingress of foreign matter such as a failing or failed auxiliary belt. If the auxiliary belt weakens, fibres can become trapped under the cambelt, causing the belt to jump or fall away.

Your cambelt naturally experiences wear and tear over time. Always take it to a professional garage if you think there may be a problem. For peace of mind that your cambelt is in order, always have your annual car service so that any problems can be identified and repaired.

What to do if the cambelt breaks?

It’s a good idea to get your car regularly serviced so any potential issues with your cambelt can be quickly identified and prevent it from becoming a more serious problem. Even a slight issue with your cambelt can be catastrophic for your car engine, so it’s important to get it looked at regularly.

If your cambelt belt does break, the engine will stop which may mean that systems that rely on it could feel different. For example, the power steering may become heavier, and after a couple of applications, your brake pedal could become harder resulting in greater pressure being required to slow down. Should this happen, try and pull over to a safe place and call your breakdown service immediately.

How much does a cam belt cost?

The cost of a new cambelt will vary greatly depending on the make and model of your vehicle. Lower-end prices can be around £250, with timing chains being over £1,000 as they can often require the removal of the engine to enable replacement. A quote for a new cambelt should include the price of the belt, water pump (if required) tensioners and the cost of labour.

At Halfords, we stock a range of timing belts and timing chains for a range of vehicles. You can search by your car registration to find the right belt or chain for you with options for home delivery or click and collect.

Shop replacement timing belts

If you suspect there could be an issue with your cambelt, book an appointment online for a free cambelt check at your local Halfords Autocentre and one of our experts will take a look and provide you with a quote for a replacement.

Book free cambelt check

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