Hi everyone, just started my first ever attempt at changing a cam belt, on my Discovery 200tdi which I use for RTV's when I'm able to ,anyway, I digress, just stripped everything of and removed the timing chest cover to find the belt still in one piece apart from a section approx 7" long, where all the teeth had stripped off, just leaving the belt backing holding it all together. Is this normal/typical of cam belt failure?, or does it indicate some other problem?, engine still turns over fine,on the starter, also , strangely, this problem occured when the engine was ticking over!?, any thoughts/experience much appreceiated