TM 5-3825-229-14&P
6-4. CYLINDER HEAD AND VALVES (cont)
a. Removal (cont).
(1) Place cylinder head on bench with exhaust side down.
NOTE
Place valves, springs, retainers and wear plates in a rack as they are removed from cylinder head so
they can be identified and reinstalled in their original locations.
(2) Using a valve spring compressor, compress valve springs (4). Remove valve spring retainer locks (2) and
valve stem caps (1).
(3) Release valve spring compressor tool and remove valve spring retainers (3), valve springs (4) and valves (5).
(4) Remove valve spring wear plates (7) and valve stem seals (6). Discard valve stem seals (6).
(5) Remove valve guides (8) by pressing them out through bottom of cylinder head using a valve guide removal
tool and hydraulic press.
b. Cleaning and Inspection.
(1) Clean carbon from valves, valve seats, valve guides and cylinder head ports. Remove all oil and crankcase
deposits from rocker arm assemblies and push rods.
(2) Inspect valve stem caps for cracks and wear. Replace valve stem cap if cracked or worn.
(3) Replace valves if they are cracked, bent, burned or warped, or if stems are worn.
(4) Check rocker arms for cracks, galling, scoring or wear. Replace rocker arm and ball if excessively worn.
(5) Inspect rocker arm locknut threads for wear.
(a) Measure the rocker arm locknut breakaway torque from operating position using a torque wrench.
(b) Use the torque wrench to remove rocker arm locknut and observe any increase in torque.
(c) If the removal torque increases more than 20 in-lb (2.3 Nm), replace rocker arm stud.
(d) To replace a worn or damaged rocker arm stud, unscrew the stud using the lower nut. Coat lower threads of
new stud with oil and install. Rocker arm studs are installed, starting with a long stud on each end, then a
short, long, short, etc., ending with two short studs in center of head.
(6) Inspect rocker arm balls for cracks and wear. Replace rocker arm ball and arm if it is cracked, worn or
damaged.
6-3
