Timing Chains are not Forever

One of the most common misconceptions I see within the automotive industry is the fact that timing chains will last the lifetime of the vehicle. It has led to the belief that once a chain has been fitted into the engine that it will never need to be serviced or replaced. After all, it’s made of metal, which is more durable than a rubber based timing belt, and it’s self lubricating meaning that as long as the oil is kept fresh the chain will be in perfect condition. Unfortunately, like the majority of engine components this is not the case.

What is the Purpose of the Timing Chain?

The timing system is one of the most crucial parts of the engine. It keeps the camshaft and crankshaft in sync to ensure that the valves and pistons do not collide. The chain is linked to sprockets or VVTs attached to the end of the camshaft(s) and to the crankshaft pulley. Guide rails and tensioners are used in unison to create a strong tension in the chain as without this it can slip and become desynced.

How can the Chain Fail?

There are a few causes for a timing chain to prematurely fail, however it is typically due to poor maintenance of the vehicle. While all components are prone to natural wear & tear over time the lifespan of the part can be extended with the correct care.

Infrequent Oil Changes

Not changing the oil often enough is one key reason for failure. The oil is responsible for keeping the parts lubricated. As time passes and it is exposed to more heat and gases from the engine, the oil will become thicker and will fail to cover as much surface area as before. Ultimately, this can lead to the timing chain operating with metal on metal contact, greatly accelerating the wear.

Incorrect Oil Use

In addition, the wrong type of engine oil can also cause these same issues. It is recommended to follow the vehicle manufacturers specifications when choosing the right oil to top up the engine. Using incorrect oil can lead to similar issues mentioned in the previous paragraph.

Failing Components

As the timing system is made up of many components, it’s not the failure of the chain alone that can bring it to a halt. It makes use of tensioners and guide rails to ensure that the chain has the correct tension, as without this it can jump and become desynced. It is not uncommon for low quality or poorly installed guides and tensioners to fail and this is one of the more common causes.

What Happens when it Fails?

In the event of a failure the worst case scenario is that the valves and pistons will collide causing catastrophic failure. As these parts are vital for the combustion sequence, necessary for the engine to function, this damage can bring the vehicle to a standstill. If the cause of failure is due to the chain snapping, bits of metal will shoot around the engine bay like shrapnel, potentially causing extra damage.

As the valves and pistons are right in the centre of the engine, the disassembly required to access and replace them will incur high labour fees.

How do I Know if my Chain is About to Fail?

One of the most evident signs of timing chain failure is an audible rattling noise from the engine bay. As the chain loses tension, either due to wear or a faulty guide/tensioner, it will lose the tight grip that it has on the sprockets. This causes a very distinct death rattle from the engine and is a sign that the timing chain needs to be checked as soon as possible.

Other signs of timing chain failure include:

• Check engine light turning on
• Oil contaminated with metal shavings
• Engine misfiring
• Lack of acceleration
• Engine not starting

In Conclusion

Overall, it’s important to keep in mind the fact that all engine components are susceptible to failing. While timing chains are considered by some to be stronger than timing belts, they are still prone to failure without proper care. It is vital to look after the engine and ensure regular maintenance is carried out in order to prolong the life of the vehicle.

GT Automotive Timing Chain Kits

At GT Automotive we stock an extensive range of timing chain kits, covering the most relevant applications in the aftermarket. All parts are stocked and dispatched from our Oxfordshire based HQ and are carefully tested and inspected before being sent out. All of the metal components come pre-lubricated for added protection up-to and during installation. Our TCKs promise to match or exceed OE quality. Discover more about the quality of our Timing Chain Kits>