The most irritating of all routine maintenance for car owners. Replacing the timing belt is a delicate exercise in keeping perhaps the most important self-maintenance item in your engine in working order.
A timing belt acts as the conductor, operating all the essential components that kickstart your car’s engine when you turn your key.
When one breaks, it can have a significant impact on your ability to drive. However, fixing it yourself isn’t quite as straightforward as other vehicle checks.
Here is a guide to changing and replacing your timing belt.
Is it time to change my timing belt?
Timing belts are designed to keep your vehicle’s crankshaft in sync with the camshaft, ensuring the engine valves and pistons operate in sequence.
While production advancements have made them relatively durable on modern models, your timing belt will still need to be changed roughly every 60,000 miles.
Some common issues and signs it might be time to change your timing belt include:
The Engine Won’t Turn Over
What are the signs? A damaged timing belt will allow the starter to engage when you start the vehicle, but your motor will fail to ignite.
What are the signs? A worn-out belt can cause pistons to malfunction due to the valves being out of sequence, this will affect the fire rate of the now damaged engine.
What are the signs? An audible ticking noise is a huge red flag that your timing belt has broken to the point it’s causing combustion issues.
Cracked Timing Belt
What are the signs? A frontside oil leak is the most common sign of a cracked timing belt. Damage allows oil to seep through the cover held in place by nuts and bolts that can loosen over time. This may also be signified by your engine overheating.
Note: The owner’s manual can help direct vehicle owners towards other suspected signs of damage to their timing belt so keep yours close.
How regularly should I change my timing belt?
The regularity with which you should change your timing belt is debated amongst experts, but most agree it should be every four years, or when you’re above the 60,000 miles mark. Mileage is often a greater factor in the condition of your belt than age.
However, if you’re experiencing any of the red flag faults listed in the previous section, you should get your car checked for damages.
A routine servicing at a garage will look for oil leaks or belt contamination, both signs and factors of early belt failure.
How to do a visual assessment of your timing belt
While you should look to replace your timing belt at the aforementioned intervals and at the manufacturer’s suggestion, it’s still a good idea to do a routine visual inspection on your vehicles every 10,000 miles.
On most standard cars this process is simply a case of removing the plastic timing belt cover on the front of the engine. This will usually be held by a couple of Phillips head screws or clips. Some vehicles are more involved when it comes to assessments, but the belt will always be accessible in some way and found outside of the engine. Consult a professional or your repair manual if you’re unsure.
To inspect the belt properly, follow these steps:
- Assess the exterior of the belt for tiny cracks.
- Assess the rubber for damage, it should be fairly smooth with no chunks missing. Cracking all over the surface is a sign of damage or extreme wear.
- Flip the belt over gently to inspect the teeth. This can be done from the point furthest from both pulleys. You may struggle to flip the belt, but you can look under it and get a good appreciation of the condition.
- Compare things that don’t quite look right against your car manual for signs of damage.
Don’t underestimate the signs of damage. One broken tooth can be catastrophic for you and your vehicle, so don’t think you can plough on without addressing the belt’s needs.
Don’t hold off on this work, as the longer damage persists the likelihood of money coming out of your pocket or a claim on your car insurance becomes more real.
What is the price for a new timing belt?
Timing belts themselves are relatively cheap, but the cost will come in the labour and services taken to fix or replace it.
Replacing the average timing belt can cost anywhere between £200 and £600. It will vary depending on the degree to which you are seeing damage, and whether the belt snaps, or you’re just seeing signs of oil leaking.
Timing belts on larger vehicles such as 4x4s and HGVs will sit at the higher end of this spectrum, costing significantly more to replace.
Can I replace my timing belt by myself?
Considering timing belts play such an essential part within everyday vehicles, we advise contacting a professional mechanic to carry out the work on your behalf.
Lining up a timing belt incorrectly can have disastrous consequences and lead to significant long-term damage. Make sure you’re leaving nothing to chance on a vehicle you plan to be driving again soon.
What’s the difference between a timing belt, a cambelt and a timing chain?
Timing belts and cam belts are essentially the same components. They both play the same role in your engine, keeping the camshaft in order and handling the opening and closing of valves to maintain timely combustion. When your cambelt breaks, you can follow much of the same instructions listed above.
Timing chains, however, are slightly different. While timing and cambelts are made out of toughened rubber the timing chain is a more typical metal chain.
Timing belts feature squared-off teeth grooves to ensure the positive drive is maintained in high-pressure situations, whereas a driving belt will feature slightly sloping sides which wedge them into place and drive alternators and air conditioning pumps.
They both have the same job, but in their own ways.
A timing chain doesn’t have a maintenance schedule and operates within the engine. However, chains are reliant on regular oil changes to avoid blocked oilways to reduce oil pressure. It’s much cheaper to maintain the oil on your chain than outright replace it, as that requires engine dismantling.
If you’re still unsure of which one you have, contact the manufacturer or check your vehicle guide.
How can I tell if my used car has had the timing belt changed?
As the most expensive routine maintenance job on a car, drivers want to know when their car was last given this vital update.
Unfortunately, there’s no catch-all way of checking whether or not the timing belt has been changed. Any signs of this will depend on the method of replacement the previous owner used. You can also lift the case to check the branding on the belt. If it looks new, it’s likely been replaced recently.
Does Carfax show car timing belt changes?
For American readers, typical vehicle maintenance such as timing belt changes will not always appear in a Carfax record, unless recorded by the previous owner.
Readers in the UK can attempt to find this information out using the .gov MOT checker.