Hi Guys!,

I have a 2001 Mondeo Zetec S, 2,5 V6.

After around 3000rpm there is a knocking that sounds timing chain related still starts and drives fine besides knocking, although not driven for long.

Is there anything that is prone to failure i.e. plastic guides or tensioners?

any help or advise would be appreciated.

Thanks! in advance.

Knocking on the V6 is not usually good news.

Big end/crankshaft bearing on the way out. Hope it's not that but they are known for it.

yeah have heard they are prone for it, although not big end i believe, it will start tapping more than a knock, if you give it more gas, even the tinniest bit the noise stops?

Could be timing chain?

Yeah this is what i was thinking, i imagine chain is fine i was just wondering if anyone has heard of any common problems with tensioners or guides or anything :/

All I know is that if you replace the chain you need to replace the tensioner and guides too. If they are worn it will reduce the life of the new chain.

couldnt agree more with Rick.

Either you replace everything or nothing to be honest.

the tensioners are aged, weakened and when you take the tension off them they will move and become more brittle, then you put a new tight chain or belt on there and all of a sudden your looking at a strong belt with poor support, the tensioners will go first, in which case there was no point changing the belt...

Oh of course i would change everything in one go, seeings as i would have the engine stripped, i may swell change the rest :)

Definately worth it!

To be honest theres no common problem as such, just the age affects them. Just as long as you lock the timing when you change the belt you will be fine :)