TM 10-4320-315-24
4-4.
MAINTENANCE OF CYLINDER HEADS - (Cont)
(b)
Slowly release valve springs (1) and remove spring compressor.
(c)
Remove spring caps (3) and valve springs (1). Remove valves (4).
(d)
Remove valve rotator (5) and spring (6).
b.
INSPECT.
(1)
Clean and inspect cylinder head. If cylinder head is cracked or damaged, replace complete cylinder
head assembly.
NOTE
Seating surface must be flat and free of burrs and scratches.
(2)
Measure valve springs (Figure 4-3). Valve spring length must be greater than 2.2 in. (56 mm).
Replace defective spring.
Figure 4-3. Valve Spring Measurement
c.
REPAIR.
(1)
Check head seating surface (1, Figure 4-4). Reface damaged seating surface on cylinder head.
(2)
When refacing seating surface, make sure a 0.23 in. (5.84 mm) minimum distance must be
maintained between seating surface and head crown. Measurement is taken with intermediate ring
installed.
(3)
Install a valve in cylinder head.
(4)
Measure distance between face of valve and cylinder head seating surface with intermediate ring (2)
installed.
(5)
If measurement does not exceed 0.224 in. (5.689 mm), go to step (9).
4-6
