84. Intake Manifold Installation - Lower
Intake Manifold Installation - Lower
1. Important: All gasket-mating surfaces need to be free of oil and foreign material. Use GM P/N 12346139 (Canadian P/N 10953463) or equivalent to clean surfaces.
With gaskets and seals in place apply a small drop 8-10 mm (0.31-0.39 inch) of RTV sealer GM P/N 12378521 (Canadian P/N 88901148) or equivalent to the 4 corners of the intake manifold to block joints (1).
2. Install the lower intake manifold.
3. Notice: Maximum gasket performance is achieved when using new fasteners, which contain a thread-locking patch. If the fasteners are not replaced, a thread locking chemical must be applied to the fastener threads. Failure to replace the fasteners or apply a thread-locking chemical MAY reduce gasket sealing capability.
Notice: Failure to tighten vertical bolts before the diagonal bolts may cause an oil leak.
Apply sealer GM P/N 12345382 (Canadian P/N 10953489) or equivalent to the lower intake manifold bolt threads.
4. Notice: Refer to Fastener Notice in Service Precautions.
Install the lower intake manifold bolts.
1. Tighten the center lower intake manifold bolts (1, 2, 3, 4) in sequence to 20 Nm (15 ft. lbs.).
2. Tighten the visible corner lower intake manifold bolts (5, 8,) to 25 Nm (18 ft. lbs.).
3. Tighten the hidden corner lower intake manifold bolts (6, 7) to 25 Nm (18 ft. lbs.).
5. Inspect the heater inlet pipe and seal for damage and replace if necessary.
6. Install the heater inlet pipe stud, if necessary.
Tighten the heater inlet pipe stud to 35 Nm (26 ft. lbs.).
7. Install the heater inlet pipe.
8. Install the heater inlet pipe nut.
Tighten the heater inlet pipe nut to 25 Nm (18 ft. lbs.).
9. Inspect the fuel rail, fuel injectors, and fuel injector O-rings for damage and replace if necessary.
10. Lubricate the fuel injector O-ring using GM P/N 12345616 (Canadian P/N 993182) or equivalent.
11. Install the injector nozzles into the lower intake manifold injector bores.
12. Press on the injector rail using the palms of both hands until the injectors are fully seated.
13. Install the fuel injector rail bolts.
Tighten the fuel injector rail bolts to 10 Nm (89 inch lbs.).