Jonathan Jablon

Just removed valve cover and found one of the rockers to be darker in color than the others. Wondering what could have caused this.

Coosawjack

Looks like no oil......oil is puddled in the valve stem end of all the other rockers!!

08'MustangDude

Not enough oil. The little oil it's getting is baking under the heat, and leaving all that
carbon build up. Can't tell from the picture if the push-rod is also dark and carboned
up, because the far left one looks dark in the picture as well.

There is puddled oil in there, it's just darker, and not as much as the others.

Either, it is an oil delivery issue, or that one is running hotter than the other ones,
but that can also be due to lower oil flow there. If that cylinder is running lean,
that exhaust valve can run hotter.