diesels always hit, iirc it's a twit of a job on a t4,
valves themselves are quite cheep scrap heads to pillage bits from are cheeper still, but i would really recommend dial gauging the the tops of the pistons before trying to fix it, just to make sure there all still coming up to where they should. depending how hard it decided to hit it may just need a couple of valves or it chould be valves, rod, piston, con rod, tappets, cam even cyl head
