Intake Manifold Replacement - Lower

Removal Procedure

^ Tools Required
- J 23600-B Torque Angle Meter





1. Remove the upper intake manifold.





2. Remove the fuel lines at the fuel rail and the bracket.
3. Remove the fuel rail with injectors.
4. Remove the power steering mounting bolts. Support the pump aside.





5. Remove the inlet cooling pipe from the coolant outlet housing.
6. Remove the heater by-pass at the coolant pump and the cylinder head.
7. Remove the radiator hose at the heater outlet housing.
8. Remove the water outlet housing.
9. Remove both of the valve rocker covers.

Important: Retain the washers in the same orientation on the center bolts.





10. Remove the lower intake manifold bolts and DISCARD the bolts.
11. Remove the lower intake manifold.





12. Loosen the rocker arms.

Important: Keep the pushrods in order. The pushrods must be installed in the original position.





13. Remove the pushrods.





14. Remove the intake gasket.
15. Inspect the flatness of the inlet flanges.
16. Clean the following items:
^ Gasket material from the mating surfaces
^ Excess RTV sealant from the front and the rear ridges of the cylinder
^ The block
^ Sealing surfaces
Use degreaser in order to clean the sealing surfaces.

Installation Procedure





1. Install the new design intake gasket, P/N 89017279.





2. Install the pushrods.

Notice: Refer to Fastener Notice in Service Precautions.

3. Install the rocker arm bolts.

Tighten
Tighten the bolts to 10 Nm (89 lb in.) + 30°.

3.1. Install the pushrods in their original location.
3.2. Coat the ends of the pushrods with prelube GM P/N 1052356, or the equivalent.
3.3. Intake pushrods are 144 mm (5.75 inch).
3.4. Exhaust pushrods are 152.5 mm (6.0 inch).
3.5. Ensure that the pushrods seat in the lifter.





4. With gaskets in place apply a small drop 8-10 mm (0.31-0.39 in) of RTV sealer GM P/N 12346141 to the 4 corners of the intake manifold to block joint (1).

5. Connect the 2 small drops with a bead of RTV sealer that is between 8-10 mm (0.31-0.39 in) wide and 3.0-5.0 mm (0.12-0.20 in) thick (2).





6. Install the lower intake manifold.
7. Install NEW lower intake manifold bolts.






Revised Updated Torque Specification, Bulletin #vss20030024

The torque specification is a 2-step process; tighten the vertical lower intake manifold bolts (the four middle ones) to 7 Nm (62 lb in). Tighten the diagonal lower intake manifold bolts (two on each end) to 7 Nm (62 lb in).Tighten the vertical lower intake manifold bolts (the four middle ones) to 13 Nm (115 lb in). Tighten the diagonal lower intake manifold bolts (two on each end) to 25 Nm (18 lb ft).

8. Install the water outlet housing.
9. Install the radiator hose to the thermostat housing.





10. Install the heater inlet pipe to the thermostat housing.

Important: Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.





11. Install the fuel injector rail assembly.
A. Install the fuel injector O-rings using GM P/N 12345616.
B. Install the injector nozzles into the lower intake manifold injector bores.
C. Press on the injector rail using the palms of both hands until the injectors are fully seated.

12. Install the fuel injectors rail bolts.
Tighten
Tighten the fuel injector rail bolts to 10 Nm (89 lb in).

13. Install the fuel feed and return pipe retaining clip.





14. Install the fuel feed and return pipe retaining clip bolt.
Tighten
Tighten the fuel feed and return pipe retaining clip bolt to 8 Nm (71 lb in).






15. Install the upper intake manifold.
16. Install the valve rocker covers.