Next, we wanted to look at the valves and combustion chamber from the inside of the cylinder. To do this, we screwed the mirror attachment to the camera before lowering it through the spark plug hole.
With the 90-degree mirror attachment, we were able to look at the valve and valve seat. You could easily spot a burnt or bent valve here. One issue is the mirror attachment reduces the image size and clarity, as you can see in these pictures.
Here we were inspecting the head gasket fire ring's condition with the 90-degree mirror attachment. You could spot a blown head gasket easily with this without removing the head. Even with the mirror heads reduced resolution we could still see things no problem.
Here we were inspecting the thrust side of the cylinder. As you can see, you can still see the original honing cross hatching on the cylinder walls, but there is some minor scuffing and scratching. The bore is still in pretty good shape though.