Lack of oil from rocker arm

Hi,

Do you mean there is no oil supply to 4 of the rocker arms or the oil isn't draining from the cylinder head?

If it is lack of supply, something is blocked. If you have oil to all except 4, chances are there is a build up of sludge or corrosion. If the problem is oil isn't draining from the head, then the ports in the head which allow oil to drain back to the oil pan are plugged.

Let me know the specifics.

Joe