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When to change the timing belt, and what if the interval is missed?
The timing belt is changed at the interval given by the car's manufacturer. The interval is usually stated both in kilometres and in years, and the belt is changed at whichever limit comes first. If the change is skipped and the belt snaps, the engine stops, and in many engines the result is serious engine damage.
Where to find your car's interval
The interval is in the car's service schedule, which you will find in the service book or owner's manual. It depends on the make, model and engine, so different engines in the same model can have different intervals. There is no general figure that fits every car.
Not every car has a timing belt. Many engines have a timing chain instead, which is designed to last longer and usually has no regular replacement interval of the same kind. The owner's manual or service book tells you which one your car has.
Why the time limit applies even if you drive little
The belt is made of rubber, and rubber ages even when the car is hardly driven. That is why the interval includes a time limit too. In a city car used for short trips, the time limit is often reached long before the mileage limit.
If you buy a used car, look for a receipt or a record of the timing belt change. A note that the car was serviced does not tell you whether the belt was changed at the same time. If you cannot find any record of the change, it is safest to assume it has not been done.
What can happen if the interval is exceeded
The timing belt keeps the engine's crankshaft and camshaft in step, so that the valves open and close at the right moment. When the belt snaps or its teeth give way, the engine stops immediately and cannot be started again until it has been repaired.
In many engines the pistons and valves can then hit each other. That damages the inside of the engine, and the repair costs considerably more than the belt change would have. In some engines this does not happen, but you are still left stranded at the roadside.
A belt does not usually give any warning that it is wearing out. That is why the interval is best treated as a limit, not as a target you can drive a little past.
What the change includes
When the belt is changed, the tensioner and idler pulleys are often replaced too, and in some engines the water pump, because they sit in the same place and are easiest to replace at the same time. What is worth replacing in your car depends on the engine. When you ask for a quote, ask which parts are included in the price.
How to ask for a quote
Timing belt replacement is done on our own premises according to the manufacturer's interval, and the price is agreed by quote. Call or send a message and tell us the car's registration number, make, model and engine, the mileage, and when the belt was last changed, if you know. If the change coincides with a scheduled service, let us know that too. We explain the difference between the two types of service in our article on scheduled service or basic service.
Timing belt change coming up?
Timing belt replacement: price on request. This work cannot be booked online.