Timing belt and timing chain replacements

May 14, 2020
Timing belt and timing chain replacements

What are they and why are they replaced?

Generally speaking the engine is split into 2 parts and these sections (camshaft & crankshaft) need to be kept perfectly timed together. This is achieved by having a timing belt (also known as a cambelt) or a timing chain connecting them together. It's a vital part of the engine and if the belt or chain was to malfunction or the timing was to come out of sync it can cause catastrophic damage to the engine.

Essentially, the timing belt and chain are considered one of the most vital components within the engine. Quite simply your engine will not run if any of the timing components break or move out of timing.

Timing Belts

It is recommended that timing belts are changed as part of the vehicles servicing routine. Each manufacture will have their own guideline of how often to renew the belt, normally in years and miles. For example some may say every 4 years or 50,000 miles (whichever comes first), others can be as high as every 10 years or 140,000 miles.

When we renew a timing belt we always use a full timing belt kit, this ensures that all aspects of the timing system are replaced including the tensioners and idler pulleys. Some garages will offer a cheaper rate but will only renew the belt, rather than the whole kit.

On some vehicles the water pump is also powered by the timing belt and we will always change the water pump at the same time. The last thing you want is to commit to a scheduled timing belt change to then find in 4 months time the water pump starts to leak, or even worse it fails and takes out the timing belt too.

If a timing belt is to fail it will generally cause major damage to the engine often running into £1500+ bills for engine rebuilds, it is also possible for the engine to be beyond repair resulting in an engine swap. Therefor regular changes of the timing belt will not only save you money but also the stress of your vehicle being off the road.

Timing Chains

Some cars are fitted with a chain instead of a belt and these are considered maintenance free e.g. they won't have a replacement schedule like a belt does. This makes it incredibly important to act upon any engine symptoms or sounds as soon as they appear as it could be a sign the chain or part of the timing chain setup is failing. The chain consists of many components including tensioners, chain and guide tubes.

As a timing chain isn't part of a service routine it is essential to act upon any issues, symptoms or sounds that may occur during engine start up or normal running. Some symptoms to look out for are

  1. A metallic rattle upon starting the engine (especially when cold).
  2. Heavy vibrations or shaking (timing issues).
  3. Metallic clinking noises from the engine whilst driving/idling.
  4. Lack of power from the engine
  5. Engine management lights on

If you experience any of these symptoms then we strongly advise for the vehicle to be checked immediately as a failure of the timing chain can potentially leave you needing a new engine.