[grumpycamel]

I am worried that a cam belt will last 120,000 miles. It doesn't have to necessarily snap to cause damage. If one or more of the teeth on the belt goes then thats enough for it to cause problems.

 

[Gromit]

There's nothing wrong with a bit of preventative maintenance, Grumpy - change it at around the 70,000 mile mark if you're worried.

My previous car had a reputation for knackering automatic transmissions prematurely (they were Jatco 'boxes of somewhat dubious reputation) so - on the recommendation of my Tame Mechanic - I had the fluid changed at 60,000 miles. The Jaguar main dealer thought I was crackers but I had the last laugh - it was still running beautifully when I sold the car with over 100,000 miles on the clock and no transmission troubles at all.

 

[Boxbrownie]

Actually with a timing belt if you do loose a few "teeth" from the belt you wouldn't even notice it, as each pulley is griped by many more teeth than would be the case with a chain sprocket system.
Virtually all the failures we ever saw in development vehicles were due to a faulty belt structure (very rare) or physical damage caused when the new belt was fitted, ham fisted levering etc.
Usually the belt will start to delaminate from an edge and the first sign will be a strange noise as a bit of cord from the belt structure whizzes around inside the cover making a **** of a racket. It is very rare for a belt to just snap without some kind of noise first, but a chain can in fact keep going up until it just gives way a link as the tensioner will keep it all tight.
Basically either way is a good design, and either design can have flaws.........Russian roulette anyone?

 

[billybentley]

Big difference is at 5 years 50000 miles. Mr Audi wants £500 to change the belt. With a chain you can keep that money in your pocket. Or allow the wife to spend it !!!

 

[grumpycamel]

There's nothing wrong with a bit of preventative maintenance, Grumpy - change it at around the 70,000 mile mark if you're worried.

I agree with you Gromit, a bit of preventative maintenance can save you a **** of a headache later.

 

[grumpycamel]

Actually with a timing belt if you do loose a few "teeth" from the belt you wouldn't even notice it, as each pulley is griped by many more teeth than would be the case with a chain sprocket system.
Basically either way is a good design, and either design can have flaws.........Russian roulette anyone?

Thats good to know BB. Lets face, most cars won't make past 60,000 miles before they're out of warranty. If the belt snaps at say 100k miles and is 6-7 years old, you'll be lucky to get a goodwill gesture out of Audi.Whatever happened to the "safe" engines that the Toyota and other Japanese manufacturers were developing? It has a set of internal cogs that allow the engine to spin down safely if the belt snaps, hence only a belt replacement is necessary instead of engine rebuild.

 

[grumpycamel]

Big difference is at 5 years 50000 miles. Mr Audi wants £500 to change the belt. With a chain you can keep that money in your pocket. Or allow the wife to spend it !!!

With chains they do stretch over time but the pre-tensioner takes care of that but occasionally they may need replacing if the engine starts sounding too rattly. Owned a few Saabs and BMWs to know that.I tend to use an independant VW-Audi specialist after the car gets to about 6-7 years old. I find that any goodwill that Audi gives for repairs decreases to nothing towards that age. The independant specialist has changed the timing belt on several of my Audis and has always been around £350 total including water pump. He only uses genuine Audi parts as well. Better than £500 but not as good as keeping your money in your pocket!

 

[Boxbrownie]

The only "safe" engine is the non-interferance design.....although not enough are nowadays, the belt/chain breaks and the engine stops, little mechanical damage but still a bill which is not welcome, but a helluva lot cheaper than the alternative of bent valves, punctured piston or bent rods, not so many are for reasons of design and requirement to fulfill emission/performance parameters.
Belts are even durable enough to run in oil nowadays, unthinkable a few years ago............tech changes, embrace it and enjoy the journey........you spent enough on it!

if any of this sounds odd blame it on the input of excess brandy tonight,,,,,cheers Anna

 

[darkmatter]

if any of this sounds odd blame it on the input of excess brandy tonight,,,,,cheers Anna

Another evening with Anna Falactic eh? Sounds like you're going steady

 

[Gromit]

On the contrary, he's sounding decidedly unsteady - probably just prior to collapsing under the weight of alcohol.

....or Anna.

 

[grumpycamel]

The images in my head.... arrrggghhh!

 

[Boxbrownie]

The images in my head.... arrrggghhh!

You should worry..............scared for life here