If valve was blocked to open rear port slightly, this would provide for lubrication and the cylinder head need not be loosened.
Nickel steel valves are used and are carried in castings or cages which screw into bosses in the cylinder head.
The whole mechanism is kept rigidly in place by the flanged hub, r, bolted securely to the cylinder head, F.
Exhaust valves, seating directly in the cylinder head, are removable through the inlet valve holes.
The valves are placed directly in the cylinder head and are operated by a common pushrod.
All valves in cylinder head, actuated by a single push and pull lever worked by a single cam.
The intake valve is withdrawn by the use of special tools through the cylinder head, the exhaust valve being first dismounted.
First off I thought Martha was goin' to choke or blow a cylinder head, I didn't know which.
Sometimes one cylinder head is cast in the same piece with the engine frame.
Then she unscrewed the cylinder head and dumped out the documents in the famous Carden case.