Valve Spring Cleaning and Inspection

Clean the valve springs in solvent.
Dry the valve springs with compressed air.
WARNING: Refer to Safety Glasses Warning .
Inspect the valve springs for broken coils or coil ends.
Measure the valve spring tension using the EN-22738-B tester. Refer to Engine Mechanical Specifications (LKW)

Fig 1: Measuring Valve Spring Tension
Courtesy of GENERAL MOTORS COMPANY
If low valve spring load is found, replace the valve springs. DO NOT use shims to increase spring load. The use of shims can cause the valve spring to bottom out before the camshaft lobe is at peak lift.