Today, we’re going to answer a few questions that regularly come up when discussing the performance of a timing chain. A timing chain is a hard-working yet sturdy component of your engine’s performance, ensuring that the pistons and valves open and close in perfect synchronisation and a range of other essential actions.

What is a timing chain?

A timing chain controls the pistons and valves in your engine cylinders, making sure they fire at precisely the right time without crashing into each other. For a full rundown of how your timing chain works, check out our article, What does a timing chain do?

All manufacturers fitted timing chains in their cars back in the good old days, yet with the introduction of new materials, most were replaced with rubber timing belts in the 60s and 70s. The new rubber options were easy to manufacture, much quieter, and easier to access and replace. However, timing chains made a partial comeback in the 90s, in specific models and marques, due to their advantages, and are once again a vital car part in the motor industry.

When should the timing chain be replaced?

Despite the suggested mileage for each marque’s timing chain replacement, most chains are expected to last the life of the vehicle. Therefore, the ‘recommendation’ for their change generally considers the expected wear and tear over those miles and the effect it can take on those chains.

At its serviceable mileage

The general rule of thumb is somewhere between 80–120,000 miles, but as you know, it’s essential to check what each manufacturer recommends in your vehicle handbook. With such a vast difference in possible ranges, it’s vital you know which is correct for your car.

When it’s wearing out, damaged, or dying

Chains stretch over time; it’s just how it is. So, if a chain elongates, even slightly, that little bit of additional slack can deliver a few tell-tale signs that it might finally be time to replace it.

If it snaps

It’s not a common problem, by any stretch, but if associated parts fail, it can lead to a timing chain snapping completely. As you can imagine, it’s a pretty serious problem, as the knock-on effect it can have on your engine can be disastrous and even fatal.

Symptoms of a failing timing chain

Engine misfires and starting problems

If the chain isn’t operating at the correct tension, there’ll be a knock-on effect on the engine performance. This can manifest in misfires, problems starting the car, its performance could feel sluggish or run low on power.

Rattling sounds

A worn chain or tensioner and a loose timing chain can cause noises from rattling and whirring to clunks and whines.

Some noises and poor performance issues will lessen as the engine warms up. This is because warming the car and engine gives the oil a chance to hit its correct working temperature and the tensioner a little time to remove some of the materialised slack. Eventually, however, the chain may suffer more stretch than the tensioner can accommodate, leading to more significant, severe issues.

What causes timing chain wear?

Lack of lubrication

The timing chain operates within the engine casing, lubricated by the engine oil. If oil levels are low, there won’t be the correct level of lubrication to keep the chain at its healthiest. Likewise, using the wrong grade or low-quality oil or oil filters can have the same effect.

If you skip services here and there—failing to change the oil and oil filter—more of the dirt and debris that accumulates under regular use will build, again, working into your timing chain and preventing its optimum operation. That gunky old oil can speed up chain wear, infiltrating the chain links, causing the damage you’d expect to avoid with regular maintenance.

Failing tensioners, guides, and silencers

Your engine uses a selection of tensioners and guides to keep your timing chain operating under ideal conditions. Some are manual and some hydraulic, but either way, if they wear out or aren’t properly maintained or operated, they can have the same effect on your timing chain, causing it to stretch or suffer over time.

Should I replace the sprockets at the same time?

If you’re going to all that effort to access the timing chain, it’s an ideal opportunity to change the complete set of sprockets, chains, and associated components. A worn or stretched chain will often impact the rest of the system, where a snug fit and precise operation are paramount.

As well as the sockets, other parts would also benefit from a check while your mechanic has access: the accessory belt, tensioner, idler pulleys, and water pump all play an essential role in your engine’s operation. Any of them can create problems that could seize your engine if they’re allowed to operate improperly and go unnoticed.

However, replacing all the components isn’t always necessary; your mechanic is ideally suited to make that call, so let them. Choosing an experienced and trustworthy garage to carry out repairs or replacements will deliver the peace of mind you need—knowing you’re getting precisely the job your car needs.

How can I protect my timing chain?

A regular maintenance and service schedule is one way to keep everything under the bonnet running as smoothly as possible. Using the correct quality and viscosity of oil along with top-grade oil filters will protect the moving parts in your engine’s operation, so they’re key factors everyone can abide by. Don’t skip your oil and filter changes—you could be asking for trouble.

Fixter can keep you safe

With a network of experienced and expert mechanics and garages, Fixter has your back, whatever the problem. If you’re concerned about a possible timing belt issue, or any other mechanical issue, we’re ready to help with our contact-free service and up to 30% savings.

About Fixter

Fixter is revolutionising the car maintenance industry, one repair at a time. Fixter was founded to make car maintenance as easy as booking a taxi. Digital, transparent and stress-free, with world-class customer service. Since launching in Manchester in 2017, Fixter has expanded to more than 100 towns and cities across the UK and provided thousands of car owners with honest, convenient and affordable car repair services.