(3). Place the valves in a numbered holder as they are removed, because each valve must be reinstalled in
the same valve guide from which it was removed.
(9) Remove the valve spring (4) and spring retainers (5 and 12).
(10) Loosen the locknut (8) and unscrew the adjusting screw (7) from the valve tappet (9).
(11) Unscrew the locknut (8) from the adjusting screw (7).
d. Cleaning. Wash all parts in cleaning solvent and blow dry with clean compressed air. Remove all carbon and
scale deposits from the valve stem, head, and face. Clean the adjusting screw and tappet threads and coat them with
engine oil.
e. Inspection.
(1) Inspect the valve stein for warpage, flaws, cracks, breaks, chipping metal, and wear. Check the valve face
for pitting, grooving, scoring, cracks, and warpage.
(2) Inspect the threads on the adjusting screw, locknut, and valve tappet. See that the threads are not worn,
stripped, or galled. Replace all damaged or worn parts.
(3) Check the valve tappet for excessive wear, grooving, pitting, etching, scoring, and flaws. Replace worn,
grooved, pitted, or scored valve tappets.
(4) Inspect the valve seats for pitting, uneven wear, cracks, splintering, and damage. If the intake valve seats
are so badly cracked, worn, or splintered that they cannot be repaired by refacing, the engine block must be
replaced.
(5) Check the valve seats for out-of-round with a dial gage. The out-of-round must not exceed 0.002 inch.
(6) Inspect the valve springs for twisting, breaks, cracks, and metal fatigue. Test the valve springs on a valve
spring tester. The proper valve spring pressure is 47 to 53 pounds with the valve closed and 103 to 110
pounds with the valve open. Replace all damaged, worn, or twisted valve springs.
f. Reseating.
(1) Make sure that the valve tappet is in low position. If the tappet is lifted, crank the engine by hand until the
tappet goes down.
(2) Apply a small amount of valve grinding compound to the valve seat.
1
Exhaust valve
7
Adjusting screw
2
Exhaust valve seat
8
Locknut
3
Valve guide
9
Valve tappet
4
Valve spring
10
Intake valve
5
Exhaust valve spring retainer
11
Lock pin
6
Lock key
12
Intake valve spring retainer
Figure 53. -Continued.
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