Intake Manifold Replacement - GMC G Service Manual

6A5-6 7.4 LITER V8
Install or Connect (Figures 4 and 5)
E
Tools Required:
J 23590 Air Adapter
J 5892-B Spring Compressor
1. New seal. Install the seal over the valve stem and
seat it against the head.
2. Spring with damper, and cap.
3. Valve keepers.
• With air pressure applied to the cylinder with
J 23590, compress the spring with J 5892-B
(figure 5).
Install the valve keepers. Use grease to hold
e
them in place.
• Carefully release spring pressure. Make sure
the valve keepers stay in place.
• Remove J 5892-B and J 23590.
4. Spark plugs.
5. Rocker arms, as outlined previously.
_
20 \ v '
21~^@ j ^ " 21 23-
2 3 -jr# ^ * ^
'26
29 32
26
— +
. - 33
29
Figure 4 — Cylinder Head and Components
20 Nut
.
21
Ball
Rocker Arm
Rocker Arm Stud
Valve Keepers
a
Cap
Rotator
.
2 7
Spring with Damper
29.
Exhaust Valve
30.
31.
Intake Valve
Pushrod Guide
Seal
33.
F-02374
| 2 3 Adjust
• Valves, as outlined previously.
Figure 5 —• Compressing the Valve Spring

INTAKE MANIFOLD REPLACEMENT

E Remove or Disconnect
. Battery negative cable.
1
2. Engine cover (G-Van).
Air Cleaner.
3.
• Drain the cooling system.
Upper radiator hose and water pump bypass hose.
4.
Heater hose and pipe (TBI engines) or heater hose
5.
(carbureted engines).
6. Wire at sensor at front of intake manifold and wiring
connectors at throttle body (TBI engines).
Accelerator, cruise control, and TVS cables, as
7.
equipped.
8. Wiring harness from clips.
9. Cruise control transducer, if equipped (R/V models).
10. Fuel line at carburetor or fuel lines at TBI unit.
. Crankcase ventilation hoses.
11
12. Vacuum hoses, as necessary.
Distributor. Refer to ENGINE ELECTRICAL (SEC.
13.
6D).
Wires at ignition coil (TBI engines).
14.
EGR solenoid with bracket (TBI engines).
15.