Bought an st170 recenly garage said guy who owned it before me done cambelt ? ive got reciept for timing belt kit but no reciept for labour because app he got his uncle to do it. sounds fair enough cos sort of thing i would do(if its expensive to fix buy the part get my old man to fit it) ive asked my ol man but he not sure. Is there a way of telling if it has been done ? without stripping stuff down?