I just finished changing head gaskets in my 351C motor. I noticed that the middle
oil return passage in the gasket as just a small hole (Maybe .093 diameter). Now after I run for a while, the
oil pressure drops and the
oil seems to be blowing out the breather cap. Its appears as though I'm filling the valve covers with oil. I checked on the old head gasket and the hole was about the same diameter.
Would I be way off base to take a drill and open up that return hole in each side?