Rocker Arm Assembly: Description and Operation

DESCRIPTION - ROCKER ARM





Rocker arms are made of light weight permanent mold aluminum alloy with a roller type follower operating against the camshaft (Fig. 35). The valve actuating end of the rocker arms are machined to retain hydraulic lash adjusters, eliminating the need for manual valve lash adjustment.

DESCRIPTION - ROCKER ARM SHAFTS





The rocker arm shafts (Fig. 36) are tubular steel and are supported by several forged aluminum alloy pedestals, which are fastened to the cylinder head. Four shafts are used, one for each intake and exhaust rocker arm bank on each cylinder head. The shafts are hollow to provide a duct for lubricating oil flow from the cylinder head to the valve mechanisms. One hollow dowel per pedestal is used to locate the pedestal to the cylinder head, orient the exhaust rocker shaft, and serve as a cam bearing oil feed passage.

OPERATION
The rocker arm is the pivot point between the camshaft lobe and the valve.