Torsional Damper And Front Crankshaft Seal Replacement - GMC G Service Manual

5. Upper radiator hose, heater hose and water pump
bypass hose.
• Fill the cooling system with the proper coolant. Refer
to MAINTENANCE AND LUBRICATION (SEC. OB).
6. Vacuum lines at the thermal vacuum switch.
7. Spark plug wires.
8. Pushrods. Be sure to install them in their original loca­
tions. Refer to "Rocker Arm and Pushrod Replace­
ment" in this section.
9. Rocker arms. Refer to "Rocker Arm and Pushrod
Replacement" in this section.
\ f \ Adjust
• Valves. Refer to "Valve Adjustment" in this
section.
10. Rocker arm cover. Refer to "Rocker Arm Cover
Replacement" in this section.
11. AIR check valve.
12. Manifold assembly. Refer to "Intake and Exhaust
Manifold Replacement" in this section.
13. Negative battery cable.
Figure 15 — Cylinder Head Bolt Tightening
Sequence
TORSIONAL DAMPER AND FRONT
CRANKSHAFT SEAL
REPLACEMENT
M Remove or Disconnect (Figure 16)
Tool Required:
J 23523-E Torsional Damper Puller and
Installer
1. Negative battery cable.
2. Radiator. Refer to ENGINE COOLING (SEC. 6B1).
3. Drive belts from the crankshaft pulley.
4. Torsional damper bolt and washer.
5. Torsional damper using J 23523-E (figure 16).
6. Front crankshaft seal. Pry out with a large screw­
driver. Take care not to distort the timing gear cover.
4.8 LITER L6 6A7-11
iL r l Inspect
• Oil seal contact area on the torsional damper for
grooving and roughness. Replace if necessary.
H Install or Connect (Figures 17 and 18)
Tools Required:
J 35468 Centering Tool and Seal Installer
J 23523-E Torsional Damper Puller and
Installer
1. Front crankshaft seal using J 35468 (figure 17). Coat
the seal lips with engine oil. The open end of the seal
faces toward the inside of the engine.
NOTICE: The inertia weight section of the tor­
sional damper is assembled to the hub with a
rubber-like material. The correct installation pro­
cedures (with the proper tool) must be followed
or movement of the inertia weight section of the
hub will destroy the tuning of the torsional
damper.
2. Crankshaft key (if removed).
3. Stud (C) (figure 18) to the crankshaft. Thread the stud
fully into the tapped end of the crankshaft.
4. Torsional damper over the end of the stud. Align the
keyway in the torsional damper shaft with the crank­
shaft key.
5. Bearing (A), washer (B), and nut (D) (figure 18).
• Turn nut (D) to pull the torsional damper into
place.
• Remove J 23523-E.
6. Torsional damper bolt and washer.
IC J Tighten
• Torsional damper bolt to 70 N*m (50 ft. lbs.).