So here I am on the Cusp of a head stud and gasket install and come to find out I may have to replace the heads due to cracks. WTH?? After talking with a respectable east coast Diesel shop they said almost 85% of the heads they pull on 6.4's are cracked!!
However I have heard very little about serious issues as a result, so I began wondering- Is this normal or a serious issue?
Analogy- None of us like seeing a new chip in the paint, but does that mean the truck will look like a New York plow truck any time soon?
So I decided to go my Ford subscription to see what the official answer is and here is what I found:
Cleaning and Visual Inspection
NOTE: The cylinder head cleaning and the cylinder head distortion check procedures are different than other engines. Watching the video prior to carrying out the procedure may be helpful if doing the procedure for the first time.
Click here to view a video version of this procedure.
NOTE: It is important that the cylinder head be thoroughly cleaned prior to taking cylinder head distortion measurements. Failure to remove carbon deposits or other material from measurement areas will result in inaccurate measurements.
Clean the cylinder head. For additional information, refer to Cylinder Head Cleaning in this section.
NOTE: Cylinder heads that contain carbon buildup in the coolant areas may show evidence of surface pitting when cleaned. Surface pitting in the coolant areas is not cause for replacement of the cylinder head.
NOTE: Staining of the metal surface is normal and does not affect sealing ability.
NOTE: Witness marks or indentations in the cylinder head resulting from the head gasket fire rings are normal and do not affect sealing ability.
NOTE: The surface finish on the cylinder head may appear to contain "record grooves", which is a normal condition.
NOTE: The cylinder head combustion chamber area may exhibit very small "surface fissures" or "microcracks" during a Magnaflux inspection process. These surface fissures or microcracks are typically located between the glow plug and the valve seats. They DO NOT extend into the coolant jacket and will not cause coolant loss or cooling system overpressurization. The presence of surface fissures or microcracks is not cause for replacement of the cylinder head.
Inspect the cylinder head for obvious signs of damage or distortion.