Valve Inspection
^ Tools RequiredJ 9666 Valve Spring Tester
J 8001 Dial Indicator
1. Use a carbon removing brush in order to clean the carbon from the combustion chambers and the valve parts. Be careful not to scuff the chamber
2. Clean the following areas:
a. The carbon and the sludge from the valve pushrods and the valve rocker arms.
b. The valve stems and heads on a buffing wheel.
c. The cylinder head and engine block gasket surfaces.
d. The bolt hole threads in the cylinder heads and the engine block.
3. Inspect the following areas:
a. The cylinder head for cracks in the exhaust ports and combustion chambers.
b. The cylinder head for external cracks in the water chamber.
c. The valves for burned heads, cracked faces, or damaged stems.
d. The valve springs for squareness.
4. Use the J 9666 in order to measure the valve spring. Replace the spring if the spring tension is less than 332-362 Nm (75-81 lbs.) at 43.43 mm (1.710 inches)
5. Measure the valve stem-to-guide clearance.
^ Excessive valve stem-to-guide clearance will cause an excessive oil consumption and may case a valve to break. Insufficient clearance will result in noisy and sticky functioning of the valve and will disturb the engine assembly smoothness.
^ Clamp the dial indicator on the exhaust port side of the cylinder head.
^ Locate the indicator so that the movement of the valve stem from side to side (crosswise to the cylinder head) will cause a direct movement of the indicator stem. The indicator stem must contract the side of the valve stem just above the valve guide.
^ Drop the valve head about 1.6 mm (0.0064 inches) off the valve seat.
^ Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading.
^ Ream the intake valve guides for oversize valves if the clearance exceeds .069 mm (0.0027 inches) on the intake valve.
^ Ream the exhaust valve guides for oversize valves if the clearance exceeds .081 mm (0.0031 inches).