Dear all, some advice needed. I have a small oil leak coming out of lower bolt of the central cover timing side horizontal cilinder. You can see that something grind the cover on the inside. Just a new gasket, new cover or is the something else going on ?
The marks are what I would consider normal at a higher mileage. The rocker pins should be a fairly good fit in the head, after a while they can move sideways and possibly oscillate with the valve. This causes the damage you can see. Theoretically you could have the cover machined flat again, I just bought new ones. Also if the pins can move too much it will damage the head.
The rocker pins do move out a little and make those marks - nothing to worry about IMO. As for the oil leak, change the gasket.
I can't see it making any difference to the noise. The pins will only be moving occasionally, are a tight fit in the holes and the whole area is full of oil...
Have to say my 996 was a lot quieter when I changed the covers, but they were in a lot worse condition. I believed the covers pushed against the pins when fitted to stop them moving sideways. After some time with the slight rotation of the pins the covers dont clamp properly.
