Chrysler Grand Voyager 2.8 CRD 2007 - Engine Noise - Tinny Rattle - Dad's taxi

2.8 CRD Grand Voyager . 56k on 2007 reg

Engine has started maikng a tinny rattling sound LHS near fly wheel casing- Is this the cam belt tensioner chain or possibly something else ?

Dont want to start removing anything unnecessarily. Appreciate if anyone has exp. of similar please before I approach the dealer garage or receive a suggestion that a ££ full investigation is called for :-(

Thanks PB