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Where is the cambelt located?
The cam belt is usually protected by plastic covers to prevent ingress of foreign objects . It is the drive belt
connecting camshaft & crankshaft .
Some people get confused between auxiliary drive belts and cam belts.
What cambelts are made from?
Cambelts
are usually made from a rubber based compound to provide
flexibility with a cord for strength. Rubber
deteriorates over time. The belt can be damaged and its
service life shortened by incorrect handling.
Getting the timing right
The Cam timing belt provides synchronisation between engine components . If fitted incorrectly
the engine may fail to start or run erratically. In some cases major engine damage may occur.
Cambelt replacement can be a complex job requiring
specialist skills and dedicated tools.
What causes the cam belt to fail?
Oil & fluid which leaks onto the belt can be injected into the belt as it runs over the pulleys, this can vary the dimensions of
the belt and cause the teeth to not mesh with the pulleys.
Seizure or collapse of bearings
of idler pulleys, pumps etc,
can cause the cam belt tension to be lost allowing
the belt to jump the teeth on sprockets causing loss of
synchronization and usually major damage.
Misalignment of pulleys can also cause premature belt failure.
How often should the cambelt be replaced?
Follow the manufacturers recommended service interval for belt replacement. Most manufacturers recommend timing belt replacement
between 40,000 and 120,000 miles. The driving cycle and operating environment will also affect replacement frequency.
Some
vehicles may require service item replacement more frequently. Cam timing belts also deteriorate with age. A vehicle covering
low annual mileage may require a timing belt change based on schedule.
How to minimise the chance of cam belt failure
Check for oil and fluid leaks onto the cam belt. Renew failing oil seals and repair leaks .
Replace the cambelt using a repair kit not just a belt.
The repair kit should contain idler bearings and tensioner. We recommend using a kit from the same manufacturer for best component
matching.
Some vehicles use the cambelt to drive a water pump etc. Check these components for wear and replace if necessary because
if the water pump etc fails this could cause the cambelt to break.
What damage occurs if the cam timing belt fails?
Cam timing belt failure causes loss of synchronisation between pistons and valvetrain. If the engine is of interference design
collision will occur between piston and valves, this may in turn cause
potential piston /conrod damage, bent or broken valves, cylinder
head damage, camshaft damage, etc.
Investigation of the damage caused by a broken timing belt almost always requires engine stripdown.
Vehicle Service History
If you have just purchased a second hand car and are unsure of the vehicle service history it is wise to have the timing belt
renewed as a precaution.
Many repairers will provide a reminder to customers when their cambelt needs replacing.
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