Lower Intake Manifold Replacement

Lower Intake Manifold Replacement

Removal Procedure

1. Drain the cooling system. Refer to Cooling System Draining and Filling (LNJ Static Fill) (Service and Repair)Cooling System Draining and Filling (LNJ GE 47716 Fill) (Service and Repair)Cooling System Draining and Filling (LY7 Static Fill) (Service and Repair)Cooling System Draining and Filling (LY7 GE 47716 Fill) (Service and Repair) .
2. Remove the upper intake manifold. Refer to Fuel Injector Sight Shield Replacement (Service and Repair) .
3. Remove the heater inlet pipe. Refer to Heater Inlet Pipe Replacement (RPO LNJ) (Service and Repair)Heater Inlet Pipe Replacement (RPO LY7) (Service and Repair) .
4. Disconnect the radiator inlet hose from the thermostat housing. Refer to Radiator Inlet Hose Replacement (LNJ Chevrolet) (Service and Repair)Radiator Inlet Hose Replacement (LNJ Pontiac) (Service and Repair)Radiator Inlet Hose Replacement (LY7).
5. Remove the fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement .




6. Remove the lower intake manifold bolts.
7. Remove the lower intake manifold from the engine.
8. If replacing the lower intake manifold, remove the thermostat and housing. Refer to Engine Coolant Thermostat Replacement (RPO LNJ) (Service and Repair)Engine Coolant Thermostat Replacement (RPO LY7) (Service and Repair) .
9. Remove the rocker arms and push rods. Refer to Valve Rocker Arm and Push Rod Replacement (Service and Repair) .




10. Remove the lower intake manifold gaskets.



Installation Procedure






Important:
* All gasket mating surfaces must remain free of oil and foreign material. Refer to Sealers, Adhesives, and Lubricants (Mechanical Specifications) for the correct part number to use to clean surfaces.

* Do not apply room temperature vulcanizing (RTV) sealer to the engine block prior to the installation of the manifold gaskets. RTV sealer is not to be placed under the lower intake manifold gaskets.



1. Install the lower intake manifold gaskets.
2. Install the rocker arms and push rods. Refer to Valve Rocker Arm and Push Rod Replacement (Service and Repair) .




3. Install the lower intake manifold seals.
4. With the seals in place, apply a small drop 8-10 mm (0.31-0.39 in) of RTV sealer (1). Refer to Sealers, Adhesives, and Lubricants (Mechanical Specifications) for the correct part number.
5. Install the lower intake manifold to the engine.





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: Refer to Fastener Notice .


Important:
* All lower intake manifold bolts need to be clean, free of foreign materials, and reused only if new bolts are unavailable. Refer to Sealers, Adhesives, and Lubricants (Mechanical Specifications) for the correct part number. Apply to the old intake manifold bolt threads.

* Manufacturer recommends the center bolts be fully torqued before the diagonal bolts to assure proper torque distribution.

* Lower intake manifold bolts in locations (6) and (7) should be torqued to specification using a crows foot type tool.



6. Install the lower intake manifold bolts.

1. Tighten the lower intake manifold bolts in sequence to 13 N.m (115 lb in) on the first pass.
2. Tighten the lower intake manifold bolts (1, 2, 3, 4) in sequence to 20 N.m (15 lb ft) on the final pass.
3. Tighten the lower intake manifold bolts (5, 6, 7, 8) in sequence to 25 N.m (18 lb ft) on the final pass.


7. Install the fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement .
8. Connect the radiator inlet hose to the thermostat housing. Refer to Radiator Inlet Hose Replacement (LNJ Chevrolet) (Service and Repair)Radiator Inlet Hose Replacement (LNJ Pontiac) (Service and Repair)Radiator Inlet Hose Replacement (LY7).
9. Install the heater inlet pipe. Refer to Heater Inlet Pipe Replacement (RPO LNJ) (Service and Repair)Heater Inlet Pipe Replacement (RPO LY7) (Service and Repair) .
10. Install the upper intake manifold. Refer to Fuel Injector Sight Shield Replacement (Service and Repair) .
11. Fill the cooling system. Refer to Cooling System Draining and Filling (LNJ Static Fill) (Service and Repair)Cooling System Draining and Filling (LNJ GE 47716 Fill) (Service and Repair)Cooling System Draining and Filling (LY7 Static Fill) (Service and Repair)Cooling System Draining and Filling (LY7 GE 47716 Fill) (Service and Repair) .