rattly old diesel!

[Rmachines]

My MK3 TDi makes a rattly noise when the revs are low and its vibrating, i have heard a lot of diesels make a squeeky rattle but mines getting worse now,  does any one know why they do this?  its not like the sound of a belt,  mabey the auto tenssioner vibrating, thats all i can think of.  Generally worse when cold,  once the revs are up and its smoothed out it stops.   It sounds almost like an un-oiled bike chain. 

Any ideas what makes this noise?

[Len]

All diesels are rattly and noisy!

[Rmachines]

Yea but i know the diffrence between a rattly diesel and a noise that wasnt there before,  I know diesels make that squeeking noise... but why? the XUD Pug engines do it a lot,  but i think its detonation or the fuel pump, this sounds similar but looser and more broken.

[danny_p]

check the cambelt pully on the cranckshaft.    it's hopefully not it  but it has a habbit of working loose on vag diesels and self machening the keyway in the cranckshaft.   if it gets exsessive it'll trash the cranck

[Rmachines]

Ok i will strip it off soon and have a look,  Cheers.