To remove the intake manifold, first drain the cooling system and disconnect the negative battery terminal cable. Next, remove the air cleaner assembly along with the air intake duct and heat tube, then disconnect the accelerator cable and, if applicable, the transmission linkage at the carburetor. Remove the bolts from the accelerator cable mounting bracket and position the cable out of the way. Disconnect the carburetor bowl vent hose, upper radiator hose, fuel line, coolant bypass hose, and label and disconnect the vacuum lines and necessary electrical connectors. If equipped with air-conditioning, remove the compressor support bracket attached to the intake manifold mounting bolt. Remove the EGR tube and the PCV hose, then unbolt and remove the carburetor and gasket. After that, remove the intake manifold mounting bolts in reverse order of the tightening sequence and take out the intake manifold, using care to break the RTV-type seal without damaging the machined surfaces. Scrape off any old gasket material from the mating surfaces, apply gasket sealant to the front and rear gaskets, and install the intake manifold seals. For 318 2-barrel engines, lightly coat the intake manifold side gaskets with RTV-type sealant, and for all models, apply a bead of RTV-type sealant to the engine block in the crevices between the intake manifold and cylinder head gasket. Carefully install the intake manifold, ensuring proper bolt hole alignment, and if necessary, use a screwdriver to realign it slightly. Install all intake manifold bolts finger-tight, then tighten bolts 1 through 4 to 25 ft-lb, followed by the remaining bolts to 25 ft-lb. Retighten bolts 1 through 4 to 40 ft-lb and then tighten the remaining bolts to 40 ft-lb, completing the installation by reversing the removal procedure. For the exhaust manifold, remove the spark plugs on 400 and 440 cubic inch engines and the alternator if needed for clearance. Detach the exhaust pipe from the manifold and remove the bolts and nuts attaching the manifold to the cylinder head, then separate the exhaust manifold from the cylinder head. When installing the exhaust manifold, clean the mating surfaces, use a new gasket, and ensure the bolts are installed with conical washers at the ends of the manifold. Tighten the manifold bolts starting from the center and working outward to the specified torque.
