GM 10039804 Manifold Asm,Intake

To remove the components, first relieve the fuel system pressure, then disconnect the negative battery cable from the battery. Remove both rocker arm covers and drain the engine coolant. Disconnect and remove the intake hose between the throttle body and the elbow at the air cleaner canister, followed by removing the distributor cap and attached spark plug wires. Mark the position of the rotor and remove the distributor. Next, disconnect the shift linkage, throttle cable, downshift cable, and cruise control cable if applicable. Unbolt and remove the throttle body from the upper plenum, then disconnect the radiator hose and fill inlet. Disconnect the inlet and return heater hose and pipe from the throttle body, along with the wiring harness, labeling all wires for reinstallation. Disconnect the heater hoses and all vacuum hoses, labeling them for correct installation. Remove the brake booster pipe and bracket, the EGR pipe, and the upper manifold plenum along with the old gaskets. Disconnect the fuel line inlet and return fittings at the fuel block, then disconnect the wires from the fuel injectors. Remove the intermediate intake manifold and old gasket, noting that the intermediate intake manifold, fuel rail, and injectors can be removed as an assembly, followed by the lower intake manifold and old gaskets. For installation, clean the gasket surfaces on the cylinder head and intake manifolds, applying a smooth, continuous bead of sealant to the front and rear mating surfaces of the lower intake manifold and the top of the block, ensuring the surface is free of oil and dirt. Place the lower intake manifold and gasket in position, tightening all bolts in the proper sequence to the specified torque, then do the same for the intermediate intake manifold and gasket. Connect the wires to the injectors and the fuel line fittings to the fuel metering block, then place the upper manifold plenum and gaskets in position, tightening all bolts in the proper sequence to the specified torque. Bolt the throttle body to the upper plenum, install the EGR pipe, and the brake booster pipe and bracket. Reattach all vacuum hoses and heater hoses, reconnect the wiring harness, install the radiator fill inlet, and reattach the radiator hose. Reconnect the inlet and return heater hose and pipe to the throttle body, hook up the shift linkage, throttle cable, downshift cable, and cruise control cable, then install the distributor. Reattach the intake hose between the throttle body and the elbow at the air cleaner, tightening the hose clamps securely. Fill the engine with coolant, install both rocker arm covers, and finally, reattach the negative battery cable, checking the ignition timing and coolant level while looking for fluid leaks.

If the engine has been removed from the car, disregard the following steps which do not apply. For vehicles equipped with air conditioning, carefully examine the routing of the NC hoses and the mounting of the compressor; depending on the system, it may be possible to remove the intake manifold without disconnecting the A/C system. If uncertain, consult a certified dealer or refrigeration specialist to have the system depressurized, and never disconnect the A/C hoses while under pressure. Begin by disconnecting the negative battery cable, draining the coolant from the radiator, and removing the air cleaner assembly. Next, disconnect the upper radiator hose, heater hose from the intake manifold, and the small by-pass hose from the water outlet on Olds engines. Disconnect the accelerator linkage at the carburetor, ensuring any supporting bracket is also removed. With a container ready to catch spillage, disconnect the fuel inlet hose at the carburetor, plugging the end to prevent dirt entry and excessive fuel seepage. Disconnect all other hoses connected to the carburetor, identifying each with numbered tape to avoid confusion during reassembly. For Chevrolet-manufactured engines, remove the distributor and secure the distributor cap with spark plug wires against the firewall. If equipped with an external coil from 1970 to 1974, disconnect the wiring at the top of the coil, marking each wire for reassembly. Disconnect the vacuum hose leading to the power brake booster if applicable, remove the upper bracket for the alternator if attached to the manifold, and remove the air conditioning compressor bracket at the intake manifold. Remove the intake manifold-to-cylinder head attaching bolts, counting to ensure all 12 bolts are removed, then lift the manifold with the carburetor free from the engine without prying on mating surfaces. If replacing the intake manifold, transfer applicable accessories such as the carburetor, temperature or oil pressure sending unit, water outlet and thermostat with a new gasket, heater hose and water pump hose adapter fittings, EGR valve with a new gasket, emission system TVS switches, carburetor choke assembly, and ignition coil and bracket for 1970 to 1974 models. Before installing the manifold, place clean lint-free rags in the engine cavity and thoroughly clean the engine block, cylinder heads, and manifold gasket surfaces, removing all extra gasket material and sealing compound. Install new front and rear seals to the engine block using RTV or an equivalent sealant, extending the bead about ½ inch up the sides of each cylinder head to seal the side gaskets. Position new manifold side gaskets on each cylinder head, using sealant around the water passages and ensuring proper mating with the front and rear seals. Lower the intake manifold into position carefully, attach the small by-pass hose to the water pump, and for Oldsmobile-manufactured engines, dip each bolt in clean engine oil before torquing the attaching bolts to specifications in the correct order. Finally, install the remaining components in reverse order of removal, fill the radiator with coolant, start the engine, and check for leaks, adjusting the ignition timing and carburetor idle speed as necessary.

Disconnect the battery ground cable, drain the radiator, and remove the air cleaner. Disconnect the upper radiator hose and heater hose at the manifold, then disconnect the accelerator linkage at the carburetor, the linkage bracket at the manifold, and the cruise control chain if applicable. Disconnect the booster vacuum pipe at the manifold, the fuel line at the carburetor (plug the line and catch any spillage), the transmission vacuum modulator line if applicable, the idle stop solenoid if applicable, the distributor wires (mark each wire with tape for ease of reassembly), the temperature sending unit wire, and vacuum hoses from the distributor, TVS, and EFE valve pipe at the carburetor (mark hoses with tape for ease of reassembly), as well as the coolant by-pass hose at the manifold. Remove the distributor cap, mark the rotor position, and remove the rotor to access the left intake manifold "six-lobed socket" head bolt, then remove this bolt with GM tool J-24394 or equivalent. Remove the accelerator linkage springs and compressor top bracket if applicable, followed by the remaining intake manifold bolts (there are 10). Lift the intake manifold, complete with carburetor, from the engine without prying on the mating edges to avoid damage. If replacing the intake manifold, transfer the carburetor and its attaching bolts, temperature or oil sending unit, water outlet and thermostat (using a new gasket), EGA valve (using a new gasket), heater hose, and water pump hose adapter fittings, as well as the carburetor choke assembly. Before installing the manifold, cover the engine cavity with lint-free rags and clean the engine block, cylinder heads, and manifold gasket surfaces, ensuring all old gasket material and sealing compound are removed. Place the new intake manifold gasket and rubber manifold seal in position at the front and rear rails of the cylinder block, ensuring the pointed end of the seal fits snugly against the block and head. Apply ATV or equivalent sealant to the ends of the seals and Copper-coat gasket sealant to the intake manifold gasket. Install the one-piece manifold gasket and carefully set the manifold in place, locating it on the engine block dowel pins, then apply Teflon pipe sealant (not tape) to the manifold bolt threads. Install the manifold-to-cylinder head attaching bolts and the rest of the bolts in the specified sequence, tightening them to the torque specifications. Connect or re-install the components in the reverse order of removal, reconnect the battery cable, close the drain plug, and refill the cooling system. Start the engine and check for leaks, adjusting the ignition timing and carburetor idle as necessary.

The initial steps for removing and installing intake manifolds on these Buick engines include disconnecting the negative battery cable, draining the radiator, removing the air cleaner, disconnecting the upper radiator hose and heater hose at the manifold, disconnecting various components like the accelerator linkage, cruise control chain, fuel line, booster vacuum pipe, and more.

Apply a 3/16-inch wide bead of RTV sealant to the front and rear manifold mating surfaces of the block, and a thin coat of RTV sealant around the coolant passage holes on the cylinder head side of the new intake manifold gaskets.

Place the TBI linkage rod into position and reattach the throttle cable, then reattach the heater hose fitting to the underside of the intake manifold. Reconnect the fuel feed and return lines, install the fuel filter bracket mounting bolt, reattach the PCV valve, elbow, and hose between the rocker arm cover and the TBI housing. Reattach the remaining vacuum lines and electrical connectors, install the coil assembly, and reconnect the coil lead and coil wire.