Warranty on new cambelt

The cam belt itself will not fail on its own inside the expected life cycle plus a bit of leeway. They do fail because of associated component failure or wear, so really if you want a definite guarantee of miles from a new belt on a second-hand engine, then you would have to replace every part of the belt train.

Another example: in perfect conditions on a test bed a tyre might last a

mrcheerful

So, what determines the renewal point- time or miles?

Brian

Both - rubber goes brittle with age so if it's left too long, even if the mileage is minimal, then it could potentially snap. But it's also advised to replace after x thousand miles if that happens first, just due to general wear and tear and stresses I suppose, on the belt.

All together now..............

Ready?

"OH YES THEY DO!"

Huw

Not in my experience, there is always an outside cause, I have never seen a cambelt just break, it does not happen (inside proper life expectancy, anyway) All the failures I have ever seen have been due to external causes, either excess age, oil/fuel contamination, seized camshaft, worn pulleys, failed water pumps, failed tensioners and idlers, stones, bolts, covers etc. Never, ever just 'I don't know why it failed, must be a faulty belt'

mrcheerful

When lined up properly, they only fail if say, a replacement has been fitted but they only fitted the belt instead of, like Zetecs, the tensioners or fully pulley kits should've also been changed at the same time - in other words, if the job wasn't done properly. Or if something else fails which then causes the belt to go.

sorry but they do fail.

i had a few months old peaugot 406 some years ago.

went to start it & the cam belt failed.

destroyed the engine.

it was under warranty so peaugot picked up the tab.

Over the years I have had belts of all kinds fail for no apparent reason. A cambelt service life is just a good guess as to when it is safe to change it before it fails. A small proportion will inevitably fail before the recommended interval. Some car manufacturers have halved the service interval before now because of a high proportion of premature failures.

Huw

So it's suck it and see, really.

Rob

As per the people at Rover, who halved the service life on their L series diesel from 84k to 48k. Came as a shock when I was told that the 25 needed doing, especially as my old 200 was done early at 60k as I didn't like taking it to the max.

Rdgs

PDH

ISTR reading somewhere that belt change intervals were devised based on taking the average mileage they let go at, and then halving it - is this remotely true?

Probably near to the mark but biassed initialy more towards information supplied by the belt manufacturer, then later on experience gained in service. You would think they would play it safe with quality belts and other components from the start but they do make mistakes. Some manufacturers make more mistakes than others.

Huw

Indeed. At this precise moment, Mystic Pete is getting the words "Vauxhall" and "Ecotec".

People didn't say Ecotec stood for "Every Component On This Engine's Crap" for nothing....