The cylinder head group consists of the cylinder head, valves, valve guides, valve springs, stem seals, valve seat inserts, cylinder head capscrews, fuel crossover, collets, spring retainer, crossheads, and the injector sleeves. The exhaust valves are manufactured from a material that is capable of operating at a higher temperature than the intake valves. The exhaust valves can be installed in the intake valve location. Do not install the intake valves in the exhaust valve location. The valve seat inserts for the exhaust and intake valves are also manufactured from different materials. The exhaust valve seat insert can be used for both intake and exhaust locations. Do not use the intake valve seat in the exhaust location.
Mark, label, or tag the cylinder head components such as crossheads, valves, and valve springs with the cylinder number and location at the time of removal. This practice will prove to be a valuable aid in diagnosing any cylinder head or component malfunctions and to make sure the reusable components are installed in their original locations.