Valve System Components
(1) Rocker arm. (2) Spring. (3) Valve. (4) Push rod. (5) Lifter. (6) Camshaft lobe.
The valve system components control the flow of inlet air and exhaust gases into and out of the cylinders during engine operation.
The crankshaft gear drives the camshaft gear through an idler. The camshaft must be timed to the crankshaft to get the correct relation between piston and valve movement.
The camshaft has two cam lobes for each cylinder. The lobes operate the intake and exhaust valves. As the camshaft turns, lobes on the camshaft cause the lifters (5) to move push rods (4) up and down. Upward movement of the push rods against rocker arms (1) results in downward movement (opening) of valves (3).
Each cylinder has one intake and one exhaust valve. Valve springs (2) close the valves when the lifters move down.