Your car’s engine contains many components, one of which is either a timing belt or a timing chain. Although the timing chain doesn’t get as much attention as some other car parts, it is extremely important. If the timing chain fails, it can cause an array of problems—including catastrophic engine damage.
Do Timing Chains Need to Be Replaced?
You may be wondering—how long does a timing chain last? Unlike timing belts, timing chains are designed to last the life of the vehicle. Of course, that doesn’t always happen. Timing chains can break for a number of reasons, which we’ll discuss shortly.
When to Change the Timing Chain
Timing belts require routine replacement—timing chains do not. Unless the timing chain is broken, stretched, or otherwise compromised, there’s no reason to change it. If there is something wrong with the timing chain, your car will likely exhibit one or more problems.
Symptoms of a failing timing chain include:
- Timing chain noise
- Engine misfire and poor performance
- Difficulty in starting the vehicle
- Illuminated check engine light
- Engine vibration or shaking when idling
- Engine won’t start
There’s a possibility you’ll hear a noise coming from the area of the timing chain cover. This noise is often caused by a loose timing chain that may be due to a faulty timing chain tensioner, guide or other issues.
More serious problems will start to arise if you ignore the early signs so make sure to give the timing chain a check as soon as you hear a noise coming from its mounting location.
What Causes a Timing Chain to Break
Some timing chains suffer design flaws from the factory. Others experience accelerated wear due to lack of vehicle maintenance (i.e. oil changes). Timing belts are not lubricated by engine oil, but timing chains are. And that makes regular oil changes vital to their longevity.
A timing chain can also fail due to a lack of tension. You see, a collection of tensioners and guides hold the chain snuggly in place. Should any of these components break, the chain will be free to slap around against other components, such as the timing cover. Obviously, that can cause severe damage to the chain.
What Happens When the Timing Chain Breaks
Your engine will stall if its timing chain breaks. If you’re driving on the highway, the engine can instantly shut down without any warning. If this happens to you, immediately and carefully pull over to the side of the road while your car still has its momentum. This can happen with any type of internal combustion engine.
Of course, a broken timing chain may have other adverse effects on your engine depending on what type it is. There are two kinds of piston engines you need to consider if you want to know what could happen when your timing chain fails.
For the first part, there is the non-interference engine. In this type of engine, the travel distance of the piston does not reach the area of the valve’s lowest point. The only thing you need to worry about if you have a non-interference engine is stalling.
However, the case is different if your car uses an interference engine. An interference engine features a piston that can travel up as far as the area where the valve reaches its lowest point.
In short, a broken timing chain will result in a collision between the piston head and the valves. And that usually means you’ll be shopping for an engine build or replacement.
What is a Timing Chain?
The timing chain keeps the camshaft(s) and crankshaft in sync. For your car’s engine to run properly, the valves, which are operated by the camshaft, need to be timed with the movement of the pistons that connect to the crankshaft. Also, on some vehicles, the timing chain drives other components, such as the water pump and balance shaft.
It’s important to note that not all vehicles use a timing chain. Some cars use a timing belt, instead.
Timing Chain vs Timing Belt
Timing belts and timing chains both serve the same purpose—and that’s to keep the camshaft(s) and crankshaft in sync. But there are differences. For one, timing belts need to be replaced periodically in accordance with the vehicle manufacturer’s maintenance schedule.
Timing chains do not require routine replacement and should last the life of the vehicle.
There are also differences in design. A timing belt is a large black rubber band that loops around the pulleys and a series of tensioners. It features teeth that hug the grooves around the outer side of the pulley. The belt has either a smooth or patterned outer surface.
Timing chains, on the other hand, are like bicycle chains, only thicker and denser. These are relatively heavier than timing belts as the chain links are made of steel.
How Much Does it Cost to Get a Timing Chain Replaced?
The cost of replacing the timing chain varies depending on where you’re having it replaced and your vehicle model. Prepare to have a repair budget of around $1,000 to $2,500 for both the part’s cost and labor if you’re expecting a timing chain replacement.
If, however, you are the DIY type, you may purchase a timing chain and install it yourself at a price of around $80 to $250. But since timing chains should be installed properly to avoid severe engine damage, consider bringing your car to a certified mechanic.