Cleaning And Inspection; Rocker Arm Stud Replacement (5.0L And 5.7L Engines) - GMC T Series 1994 Repair Manual

41
42
Figure 54— Cylinder Head and Components (7.4L
Engines)
40. BOLT
41. BALL
42. ROCKER ARM
46. CYLINDER HEAD
47. GASKET
251. VALVE KEEPERS
253. CAP
254. ROTATOR
256. SPRING WITH DAMPER
257. SEAL
258. EXHAUST VALVE
259. INTAKE VALVE
260. PUSHROD GUIDE
F9346
A. Compress the springs (256) with J 8062 (figure
55).
B. Remove the valve keepers (251).
C. Remove J 8062.
2
. Caps (253), shields (255), springs with dampers
(256), and rotators (254).
3. O-ring seals (252) (if used) and seals (257).
4. Valves (258 and 259). Place them in a rack so they
can be returned to their original position at assem­
bly.

CLEANING AND INSPECTION

6
Refer to SECTION A and perform the following:
Measure
• Valve stem clearance.
• Valve spring tension and free length.
Other information outlined includes:
• Valve and seat grinding.
• Valve guide reaming.
ROCKER ARM STUD REPLACEMENT (5.0L AND
5.7L ENGINES)
Tools Required:
J 5802-01 Stud Remover
J 5715 Reamer {0.0762 mm (0.003-inch) over­
size} or
J 6036 Reamer {0.3302 mm (0.013-inch) over­
size}
J 6880 Stud Installer
Rocker arm studs that have damaged threads or are
loose in cylinder heads should be replaced. New studs
are available in 0.003-inch and 0.013-inch oversize.
1. Place J 5802-01 over the stud to be removed.
Install a nut and flat washer. Remove the stud by
turning the nut (figure 56).
2. Ream the hole to the proper size for the replace­
ment oversize stud. Use J 5715 for 0.0762 mm
(0.003-inch) oversize studs; J 6036 for 0.3302 mm
(0.013-inch) oversize studs (figure 57).