The timing belt, also known as the cambelt, is one of the most important components of the car, controlling the timing of the vehicle’s engine – it controls the internal combustion by ensuring that the camshaft (which controls the valves) rotates in synchronisation with the crankshaft (which controls the piston) making sure that the engine’s valves open and close at the correct time during each cylinder’s intake. In an interference engine (where the piston and the valves share the same space) a snapped timing belt will cause the piston and the valves to collide, resulting in serious damage to the costly and fragile valves.
How Often Should It Be Changed?
Timing belt replacement is recommended either on a mileage or time-based change – whichever comes first, this depends largely on the manufacturer’s specifications, the vehicle’s handbook should specify the change frequency. For some cars this may be every 4 years or every 60,000 miles but for others every 6 years or 100,000 miles.
Timing Belt Inspection
In contrast to its vital function, the appearance of the timing belt is unremarkable – it consists of a simple looking rubber belt with various attachments. A worn timing belt will appear glazed and glossy on the underside, the rubber will also become brittle, this loss of elasticity leaves it more prone to damage. Other signs of wear include fraying or cracks in the rubber. When changing replacing your timing belt, it is also advisable to change the timing belt tensioners and pulleys at the same time.
What Happens If You Don’t Change Your Timing Belt?
The timing belt is an integral part of the engine and without it the engine will either fail at an inopportune moment, or not start at all. If the timing belt is not checked at regular intervals it will inevitably over time, weaken and snap, causing hundreds of pounds worth of mechanical damage in an interference engine. In the case of a car without an interference engine, the vehicle is likely to stall if the timing belt has failed but no permanent damage will be caused – although the driver may be left stranded in an inconvenient location.
Depending on the make and model of the vehicle, the cost of replacing the timing belt itself may vary from approximately £200 to up to £1000 – although the actual belt itself is cheap, the reason behind the seemingly high price is often due to the actual physical location of the timing belt, which in order to access and change, the mechanic may have to disassemble and reassemble the engine – a laborious and time consuming process.
However, if damage to the engine has already been caused by timing belt failure, such as to the valves, pistons or water pump, the price will probably be considerably more.
Metal Timing Chains
Many manufacturers prefer metal timing chains for improved longevity, although these are less likely to wear out and if they do break, are likely to cause catastrophic consequences to the engine. Some manufacturers state that the timing chain will last the duration of the life of the vehicle, others however may suggest replacement at intervals.
To find out if your vehicle has a timing belt or timing chain, as well as the guidelines for suggested replacement, check your vehicle’s manufacturer’s specification.
If you would like more information regarding timing belt replacement, or any other type of vehicle servicing requirements, please contact Longmynd Service Station.