As Iainfm said earlier the camshaft appears to have broken some time ago, the evidence being the state of the bucket showing it has not been going in and out and rotating as it should have been doing, the break is a stress fracture originating at a stress raiser in the fillet. Lucky it is 16v so the other exhaust valve for that cylinder was trying to do the work of two. Cam belt stripping/breaking caused the valve damage. So no unknowns there I believe. When you drop the sump to change the shells inspect the state of the oil strainer on the oil pump. Lubricate all well on assembly; and new filter and fresh oil as Iainfm says.
Last edited by armoore; 24-08-10 at 13:21.