Valve: Testing and Inspection

INSPECTION
VALVE MECHANISM
1. Inspect each valve for following:
a. Damaged or bent valve stem
b. Rough or damaged face
c. Damaged or unevenly worn stem tip





2. Resurface or replace valve as needed.





3. Measure length of each valve.





4. Measure diameter of each valve stem.
Diameter
Intake: 0.2152 - 0.2157 inch (5.465 - 5.480 mm)
Exhaust: 0.2138 - 0.2146 inch (5.430 - 5.450 mm)





5. Measure inside diameter of each valve guide at points shown in figure.





6. Calculate valve stem-to-valve guide clearance. Subtract outer diameter of valve stem from inside diameter of respective valve guide.
7. If clearance exceeds specification, replace valve, and/or valve guide.





8. Measure protrusion height of each valve guide. Replace valve guide as needed.

NOTE: Intake and exhaust valve guides are different. Be sure to use correct valve guide.

VALVE SEAT
1. Inspect contact surface of each valve seat and valve face for following:
a. Roughness
b. Damage
c. Pitting
d. Cracks





2. Resurface valve seats with a 45° valve seat cutter. Resurface valve faces as needed.
3. Apply a coat of Dychem blue to valve face and valve seat and allow to dry.
4. Inspect valve seating by pressing valve against seat and rotating valve 360°.
a. If Dychem blue is not removed 360° around valve face, replace valve.
b. If Dychem blue is not removed 360° around valve seat, resurface valve seat.





5. Measure seat contact width.
6. Complete seat-cutting process by lapping valve to seat using valve-lapping compound.

NOTE: Clean valves thoroughly before reassembly, and insure that all traces of lapping compound has been removed.

VALVE SPRING
1. Inspect each valve spring for cracks and damage.





2. Measure free length and out-of-square. Replace valve springs as needed.