Chevrolet 12639087 Manifold, Intake

You can Select Your Vehicle to check if 12639087 fits your vehicle.

Before removing the intake manifold, one has to first disconnect the wire from the negative terminal of the car battery and also discharge the fuel system. After that, one should take out the air filter housing outlet duct and the alternation. Remove and label all engine wiring harness that are going to be restricted by the intake manifold, remove all harness retainers and clips and secure those harness which are removed out of your way. Remove the power brake vacuum hose connection to the booster and the vacuum hose to the canister purge solenoid, the fuel line to the fuel rail, and the PCV hose to the intake manifold. Remove any of the remaining electrical connections or vacuum hoses connected to the intake manifold or to the throttle body. Unfasten the intake manifold mounting bolts ¼ turn at a time in the reverse sequence or the tightening sequence until they are easily removable by hand and you may need to use pry bar to separate the gasket if it sticks hard on the surfaces without harming the gasket sealing surfaces. Pull-forward the manifold and then unplug all the wiring harness connectors; further, detach the intake manifold and look for other hooks as it is being lifted. On the 6.0L models when changing a manifold, the fuel rail and the injectors should be removed. For installation, make sure the surfaces of the cylinder heads, block and manifold to be contacted with the gaskets are devoid of all forms of residues of the previous gasket material but should not be scraped of smooth. Dry clean the mating surfaces with safety solvent and duster and vacuum any dirt from the area. The tapped holes should be chased with a tap of the corresponding size; the holes should then be cleaned with compressed air. Place the new gaskets as they slide and click into position and will fit into the intake port holes. Ensure the manifold is placed correctly and fix the bolts and tighten them in a proper sequence and to the necessary torque, ensure do not over tighten to avoid gasket leak. The rest of the installation procedure is performed in the reverse order to the removal one; after that, start the engine and check vacuum leaks at the joints of the intake manifold.

The first step is to disconnect the cable from the negative terminal of the battery and relieve the fuel system pressure.