Cylinder Head And Valves
(1) Push rod. (2) Camshaft lifters. (3) Guide support. (4) Rocker arm shaft. (5) Rocker arm. (6) Exhaust valve. (7) Valve seat insert. (8) Inlet valve. (9) Inner valve spring. (10) Outer valve spring.
The valves and valve system components control the flow of inlet air and exhaust gases into and out of the cylinder during engine operation.
The inlet and exhaust valves are opened and closed by movement of these components; crankshaft, camshaft, camshaft lifters, push rods, rocker arms, and valve springs. Rotation of the crankshaft causes rotation of the camshaft. The camshaft gear is driven by, and timed to, a gear on the front of the crankshaft. When the camshaft turns, the cams on the camshaft also turn and cause the camshaft lifters to go up and down. This movement makes the push rods move the rocker arms.
The movement of the rocker arms will make the inlet and exhaust valves in the cylinder head open and close according to the firing order (injection sequence) of the engine. Two valve springs for each valve help to hold the valves in the closed position.
There is one inlet and one exhaust valve for each cylinder. The valve seat insert for the inlet and exhaust valves can be replaced. The valve guide bore is machined in and is a part of the cylinder head.