How can I believe Tim and Savage? Cylinder Head Close Inspection!

These pictures were taken from 10x to 30x magnification, through a microscope. Initially, I was trying to identify what small black dots were on the face of the head. I discovered a load of pits and voids across the face of the head, in the combustion dome by the valves, etc. Most were not of a troublesome size or location. However, it should be noted that it is extremely risky to take a head like this, and re-flycut it to remove material in a warped-head condition. This is because you could potentially open up a big void- it's like trying to cut away at the opening of a cave. You could make matters far worse.

The surface roughness and flatness of the surface were very good on this head, in my opinion. Again, the flatness was within 0.0005" across the entire head surface, which is kind of surprising considering everything I expected to see.

20X magnification
Coolant passage opening, edge. The discoloration is burnt coolant and carbon. Note the fracture-looking pits. Further- and of great importance- note how the sealing feature of the gasket dug into the head.

In most areas of the head, this mark looks like a rope. In this area, and along the leaking side of the head, the mark looks like a continuous groove. This is a result of the movement of the head gasket when running. The rope or cross-hatched pattern of the mark is caused by the high and low spots of the tooling that cut the head. The flycutter cuts a series of circles across the head, these circles are alternating high and low spots in the aluminum, very small indeed. As the head gasket moved, shifted, and vibrated; the tool marks were worn down so far that they are no longer visible in the problem, or leaking, areas of the head. This is important to know when you inspect your head, as it will point out very readily where the gasket was actually loose.


30x magnification

Further pitting and apparent fracturing at the coolant passage opening edge.

Note again the depth of the head gasket seat groove in the head aluminum. It is not only continuous in this photo, but it is also significantly deeper.

Again, the discoloration is burnt coolant and carbon- not black gook from the head gasket coating.



Roughly 15x

This is a further view of the bottom of the timing chain side coolant hole. Tool marks are not visible in the head gasket sealing groove, caused by vibration and shifting of the gasket.











10x
And still further away.














30x magnification


This image shows a void under 30x magnification. Again- this could be a real problem for some heads- causing leak paths, potential starts for fractures, and could make flycutting for warpage a dangerous and risky operation.