Rocker Arm Stud Replacement; Exhaust Manifold Replacement - GMC G Service Manual

6A5-8 7.4 LITER V8
2. Intake manifold, as outlined previously.
3. Pushrod, as outlined previously.
i / 1 Adjust
• Valves, as outlined previously.
4. Rocker arm cover, as outlined previously.
Figure 7 — Removing the Valve Lifter Using J 3049
Figure 8 — Removing the Valve Lifter Using
J 9290-01
ROCKER ARM STUD
REPLACEMENT
H Remove or Disconnect
1. Rocker arm cover and rocker arm, as outlined
previously.
2. Rocker arm stud. Use a deep socket.
H Install or Connect
1. Rocker arm stud.
E & l Tighten
• Rocker arm stud to 68 N*m (50 ft. lbs.).
2. Rocker arm, as outlined previously.
F I Adjust
• Valves, as outlined previously.
3. Rocker arm cover, as outlined previously.
H"H Remove or Disconnect
1. Battery negative cable.
2. Engine cover (G-Van).
3. Heat stove pipe (right side manifold).
4. Dipstick tube (right side manifold).
5. Oxygen sensor wire (left side manifold) (TBI
engines). Do not remove the sensor unless it is to be
replaced.
6. Air hose at the check valve.
7. AIR lines at manifold (G-Van, both sides).
8. Spark plugs.
9. Exhaust pipe at the manifold.
NOTICE: When raising or supporting the engine
for any reason, do not use a jack under the oil
pan, any sheet metal or crankshaft pulley. Due
to the small clearance between the oil pan and
the oil pump screen, jacking against the oil pan
may cause it to be bent against the pump
screen, resulting in a damaged oil pickup unit.
• Raise engine on G-Van only enough for clearance.
• Check for sufficient clearance between dash
10. Exhaust manifold bolts and spark plug heat shields.
11. Exhaust manifold.
M Clean
B-04576
• Mating surface on the manifold and head.
• Threads on the exhaust manifold bolts.
H Install or Connect
1. Exhaust manifold.
2. Exhaust manifold bolts and spark plug shields.
H \ | Tighten
• Exhaust manifold bolts to 54 N»m (40 ft. lbs.).
• Lower the engine on G-Van.
3. Exhaust pipe.
4. Spark plugs.
EXHAUST MANIFOLD
REPLACEMENT
panel and rear engine mounted components.
Remove components if necessary to prevent
damage.
— Tighten the center bolts first, then con­
tinue outward each way.