Hi folks , I recently bought a damaged st line x, 1.5 diesel,,I've fixed it since but a lot of people have been telling me that the cam box and belt need changed at around 70,000 miles , as no service history came with the car I'd like to know is there anyway of telling if its already been changed , i was told you can tell by the code on the cam box housing but I don't know what the code on mine signifies,, could someone help me locate a way of telling if it was done 

I'm not sure what you mean by cam box?

The cambelt is recommended at 10 years or 120,000 miles.

The cam chain does not have a replacement interval, as it was designed to last the life of the engine.  However we see these chains snap regularly so most people upgrade to the 8mm chain at the same time as the belt is being changed, unless the chain snaps early.

There is a Peugeot part number on the camchain housing that you can check to see if the chain has been replaced.  I don't know the numbers off top of my head but they were easy to find on Peugeot sites last time I needed them.