when should i change the CAM belt (or timing chain)

[anyweb]

hi guys,

my car is a merc c220 bought third hand, a german export i've had it since april 2005. It has 171000 kilometres on the clock which is quite a lot, and i do have all the original service history but no-where do i see that it has had this belt changed,

the reason i'm concerned is my mum's own merc 200, had the engine seized (cam belt went bling) and her mileage is less than mine,

so in a nutshell, at what mileage is it recommended to replace the cam belt (or timing chain)? (kilometres)

just noticed someone has posted the same question as me, except my car is petrol and theirs is diesel so i dunno if that makes a difference.

thanks in advance gurus

cheers
anyweb
http://anyweb.kicks-ass.net

 

[pascal]

Not sure about the smart car, But as far as I am aware, Mercedes dont do TIMING BELTS on road cars.


Pascal

So how your mums 200 belt broke is a mystery to me. Are you sure it was an MB

 

[anyweb]

hmm ok very strange cos i'm nearly sure that's what they said (in sligo ireland) that the cam belt/chain whatever went and the engine seized. in the end she needed a replacement engine in order to get the car driving again....

so are you saying that i don't need to replace any cam shaft belt/chain or anything like that ? or timing belt ?

cheers

anyweb

 

[woodturner-fran]

Every merc I know of has a timing chain rather than a belt (common on many many other cars). You don't change the chain, unless you are rebuilding the engine.

However, if the fanbelt broke that would stop the waterpump and the subsequent overheating would sieze the engine.
That the long flat belt that you see when you open the bonnet at the rear of the radiator. Check it for signs of wear( things like cracks on the underside, frayed parts etc et).

Replace if neccessary,

Fran

 

[anyweb]

well i'm not reffering to the fan belt (i know what that is at least), but obviously from what you are saying i;m referring to the 'timing chain'

i';m no auto mechanic so you can see i'm getting terms/words wrong but i hope you get the idea now,

when should i change the 'timing chain' bearing in mind that my mileage is now 171000 kilometres, correct me if i'm wrong but i was under the impression that these chains get loose over time and failure to replace them when loose will lead to an engine replacement.... (due to chain snapping etc...)

thanks in advance

cheers

anyweb

 

[sunking101]

Just leave it alone. If you were rebuilding the engine then it'd make sense whilst you're in there to replace the chain. Cars with timing belts are a different matter but chains are very long lasting and built that way.

 

[anyweb]

ok then, thanks for the advice,

i wonder why i have been warned to change the timing belt on the chrysler voyager we also have at 145000km,

and why did my mums car (engine) bite the dust (they said the timing chain broke causing the valves etc to destroy/damage the engine so bad it needed the whole engine replaced - merc 200)

it was because of that, that I wanted to be pre-emptive on this and replace the belt/chain before it starts to go bad

thanks anyway

cheers
anyweb

 

[woodturner-fran]

The voyager - well it may well have a timing belt (I'm just not familiar with it) and it may well need to be changed. I know on my renault scenic the belt needs to be changed every 70000 (although the main dealer will say every 50,000 to cover himself). In fact on the scenic they sell a kit and you do the belt, water pump and tensioner all in the one go. Its a right pain the **** of a job. First time I did it I got caught out - there was no key/spline on the bottom pulley so it was difficult to line up the engine when putting the tension back on the belt. Anyway, I digress.....

Of course the timing chain may well have broke.... it can happen... its just very rare. Because IIRC the timing chain is right at the back of the engine I would think you would need to take out the engine to replace it. Hence the reason why I say its only done when rebuilding an engine anyway. Kinda one of those ones where you have to balance up the cost of replacing the chain with the likelihood of it never breaking anyway and what a replacement engine might cost in a breakers yard....

Just hope it never happens!!

Fran

 

[jberks]

The only Merc I have ever heard of with timing chain issues was my dad's old 250 6cyl E class back in 1980. That used to wear the sprocket teeth until the chain just dropped off - probably a lubrication issue but as it had full dealer history, clearly a design fault. On the up side, on the 2 occasions in 150k that it failed, it didn't kill the engine.

Normally, chains go because the tensioners wear out, allowing them to jump a cog. It is usually preceded by the chain becoming noisy for a while first . If your mum is anything like mine (or my wife for that matter) she would probably have ignored it.

 

[996jimbo]

Taking up jberks point, the only issue with timing chains generally is with the tensioner. The mechanism by which the timing chain is tensioned can wear which normlly leads to poor running and starting as it screws up the timing.

At its most extreme the chain can jump a tooth though I'd imagine that would only happen due to sudden failure of the tensioner as you'd have problems running the car way before the tensioner worked so out of adjustment that the chain jumped.

Ultimately the chain like any other part can fail, but it shouldn't!

 

[anyweb]

thanks guys for the insights

so unless i'm hearing some god awful noise from the engine, i'm safe to not have to worry about replaceing my timing chain in my merc c220 with 170k on the clock

cheers

anyweb