Troy Herman spins the valve in the opening to match the surfaces
to one another.Sometimes, the cylinder heads come back from the machine shop with
the springs, valves and valve seals already installed. In this project, new
hardened valve seats and valve guides have already been installed and
were covered in the previous installment of this rebuild, so for this step,
Herman began by matching the valves to the valve openings. He
smeared a valve grinding compound on the face of the valve and the
valve opening and inserted into the opening. A valve facing tool was
placed on each valve and spun in its respective valve opening by hand
for several minutes to ensure the valve face and head surface matched.