Ok, so I’ve managed to go a little bit further with this over the weekend and pulled the head. Was just going to replace the broken rocker and retime with a new belt. Anyway, with the head off I can see that the valves have touched the pistons but remarkably the valves all seem to operate smoothly when the cams are rotated. There are 2 rockers that are visibly broken. I guess I now need to remove the cams and check all the other rockers and maybe for spun lobes.
